diff --git a/lib/api/model/events.dart b/lib/api/model/events.dart
index 0af145330..b1789e3ce 100644
--- a/lib/api/model/events.dart
+++ b/lib/api/model/events.dart
@@ -244,11 +244,11 @@ class UserSettingsUpdateEvent extends Event {
   @JsonKey(includeToJson: true)
   String get op => 'update';
 
-  /// The name of the setting, or null if we don't recognize it.
-  @JsonKey(unknownEnumValue: JsonKey.nullForUndefinedEnumValue)
-  final UserSettingName? property;
+  /// The name of the setting, or [UserSettingName.unknown] if we don't recognize it.
+  @JsonKey(unknownEnumValue: UserSettingName.unknown)
+  final UserSettingName property;
 
-  /// The new value, or null if we don't recognize the setting.
+  /// The new value, or null if we don't recognize the setting ([UserSettingName.unknown]).
   ///
   /// This will have the type appropriate for [property]; for example,
   /// if the setting is boolean, then `value is bool` will always be true.
@@ -261,17 +261,17 @@ class UserSettingsUpdateEvent extends Event {
   static Object? _readValue(Map<dynamic, dynamic> json, String key) {
     final value = json['value'];
     switch (UserSettingName.fromRawString(json['property'] as String)) {
-      case UserSettingName.twentyFourHourTime:
+      case .twentyFourHourTime:
         return TwentyFourHourTimeMode.fromApiValue(value as bool?);
-      case UserSettingName.starredMessageCounts:
-      case UserSettingName.displayEmojiReactionUsers:
+      case .starredMessageCounts:
+      case .displayEmojiReactionUsers:
         return value as bool;
-      case UserSettingName.emojiset:
+      case .emojiset:
         return Emojiset.fromRawString(value as String);
-      case UserSettingName.webInboxShowChannelFolders:
-      case UserSettingName.presenceEnabled:
+      case .webInboxShowChannelFolders:
+      case .presenceEnabled:
         return value as bool;
-      case null:
+      case .unknown:
         return null;
     }
   }
@@ -818,11 +818,12 @@ class ChannelUpdateEvent extends ChannelEvent {
   final int streamId;
   final String name;
 
-  /// The name of the channel property, or null if we don't recognize it.
-  @JsonKey(unknownEnumValue: JsonKey.nullForUndefinedEnumValue)
-  final ChannelPropertyName? property;
+  /// The name of the channel property,
+  /// or [ChannelProperty.unknown] if we don't recognize it.
+  @JsonKey(unknownEnumValue: ChannelProperty.unknown)
+  final ChannelProperty property;
 
-  /// The new value, or null if we don't recognize the property.
+  /// The new value, or null if we don't recognize the property ([ChannelProperty.unknown]).
   ///
   /// This will have the type appropriate for [property]; for example,
   /// if the property is boolean, then `value is bool` will always be true.
@@ -849,36 +850,36 @@ class ChannelUpdateEvent extends ChannelEvent {
   /// (e.g., `value as bool`).
   static Object? _readValue(Map<dynamic, dynamic> json, String key) {
     final value = json['value'];
-    switch (ChannelPropertyName.fromRawString(json['property'] as String)) {
-      case ChannelPropertyName.name:
+    switch (ChannelProperty.fromRawString(json['property'] as String)) {
+      case .name:
         return value as String;
-      case ChannelPropertyName.isArchived:
+      case .isArchived:
         return value as bool;
-      case ChannelPropertyName.description:
+      case .description:
         return value as String;
-      case ChannelPropertyName.firstMessageId:
+      case .firstMessageId:
         return value as int?;
-      case ChannelPropertyName.inviteOnly:
+      case .inviteOnly:
         return value as bool;
-      case ChannelPropertyName.messageRetentionDays:
+      case .messageRetentionDays:
         return value as int?;
-      case ChannelPropertyName.topicsPolicy:
+      case .topicsPolicy:
         return ChannelTopicsPolicy.fromApiValue(value as String);
-      case ChannelPropertyName.channelPostPolicy:
+      case .channelPostPolicy:
         return ChannelPostPolicy.fromApiValue(value as int);
-      case ChannelPropertyName.folderId:
+      case .folderId:
         return value as int?;
-      case ChannelPropertyName.canAddSubscribersGroup:
-      case ChannelPropertyName.canDeleteAnyMessageGroup:
-      case ChannelPropertyName.canDeleteOwnMessageGroup:
-      case ChannelPropertyName.canSendMessageGroup:
-      case ChannelPropertyName.canSubscribeGroup:
+      case .canAddSubscribersGroup:
+      case .canDeleteAnyMessageGroup:
+      case .canDeleteOwnMessageGroup:
+      case .canSendMessageGroup:
+      case .canSubscribeGroup:
         return GroupSettingValue.fromJson(value);
-      case ChannelPropertyName.isRecentlyActive:
+      case .isRecentlyActive:
         return value as bool;
-      case ChannelPropertyName.streamWeeklyTraffic:
+      case .streamWeeklyTraffic:
         return value as int?;
-      case null:
+      case .unknown:
         return null;
     }
   }
@@ -1405,8 +1406,9 @@ class DeleteMessageEvent extends Event {
 
   final List<int> messageIds;
   // final int messageId; // Not present; we support the bulk_message_deletion capability
-  // The server never actually sends "direct" here yet (it's "private" instead),
-  // but we accept both forms for forward-compatibility.
+  // The server never actually sends "channel" or "direct" here yet
+  // (it's "stream" or "private" instead), but we accept both the old
+  // and new forms for forward-compatibility.
   @MessageTypeConverter()
   final MessageType messageType;
   final int? streamId;
@@ -1423,7 +1425,7 @@ class DeleteMessageEvent extends Event {
   factory DeleteMessageEvent.fromJson(Map<String, dynamic> json) {
     final result = _$DeleteMessageEventFromJson(json);
     // Crunchy-shell validation
-    if (result.messageType == MessageType.stream) {
+    if (result.messageType == .channel) {
       result.streamId as int;
       result.topic as String;
     }
@@ -1434,30 +1436,6 @@ class DeleteMessageEvent extends Event {
   Map<String, dynamic> toJson() => _$DeleteMessageEventToJson(this);
 }
 
-/// As in [DeleteMessageEvent.messageType],
-/// [UpdateMessageFlagsMessageDetail.type],
-/// or [TypingEvent.messageType].
-@JsonEnum(alwaysCreate: true)
-enum MessageType {
-  stream,
-  direct;
-}
-
-class MessageTypeConverter extends JsonConverter<MessageType, String> {
-  const MessageTypeConverter();
-
-  @override
-  MessageType fromJson(String json) {
-    if (json == 'private') json = 'direct'; // TODO(server-future)
-    return $enumDecode(_$MessageTypeEnumMap, json);
-  }
-
-  @override
-  String toJson(MessageType object) {
-    return _$MessageTypeEnumMap[object]!;
-  }
-}
-
 /// A Zulip event of type `update_message_flags`.
 ///
 /// For the corresponding API docs, see subclasses.
@@ -1536,8 +1514,9 @@ class UpdateMessageFlagsRemoveEvent extends UpdateMessageFlagsEvent {
 /// As in [UpdateMessageFlagsRemoveEvent.messageDetails].
 @JsonSerializable(fieldRename: FieldRename.snake)
 class UpdateMessageFlagsMessageDetail {
-  // The server never actually sends "direct" here yet (it's "private" instead),
-  // but we accept both forms for forward-compatibility.
+  // The server never actually sends "channel" or "direct" here yet
+  // (it's "stream" or "private" instead), but we accept both the old
+  // and new forms for forward-compatibility.
   @MessageTypeConverter()
   final MessageType type;
   final bool? mentioned;
@@ -1557,10 +1536,10 @@ class UpdateMessageFlagsMessageDetail {
     final result = _$UpdateMessageFlagsMessageDetailFromJson(json);
     // Crunchy-shell validation
     switch (result.type) {
-      case MessageType.stream:
+      case .channel:
         result.streamId as int;
         result.topic as String;
-      case MessageType.direct:
+      case .direct:
         result.userIds as List<int>;
     }
     return result;
@@ -1613,7 +1592,10 @@ class TypingEvent extends Event {
   @JsonKey(includeToJson: true)
   String get type => 'typing';
 
+  @JsonKey(unknownEnumValue: TypingOp.unknown)
   final TypingOp op;
+  // The server never actually sends "channel" here yet (it's "stream" instead),
+  // but we accept both forms for forward-compatibility.
   @MessageTypeConverter()
   final MessageType messageType;
   @JsonKey(readValue: _readSenderId)
@@ -1647,10 +1629,10 @@ class TypingEvent extends Event {
     final result = _$TypingEventFromJson(json);
     // Crunchy-shell validation
     switch (result.messageType) {
-      case MessageType.stream:
+      case .channel:
         result.streamId as int;
         result.topic as String;
-      case MessageType.direct:
+      case .direct:
         result.recipientIds as List<int>;
     }
     return result;
@@ -1664,7 +1646,10 @@ class TypingEvent extends Event {
 @JsonEnum(fieldRename: FieldRename.snake)
 enum TypingOp {
   start,
-  stop;
+  stop,
+
+  /// A new, unrecognized operation.
+  unknown;
 
   String toJson() => _$TypingOpEnumMap[this]!;
 }
@@ -1743,6 +1728,7 @@ class ReactionEvent extends Event {
   @JsonKey(includeToJson: true)
   String get type => 'reaction';
 
+  @JsonKey(unknownEnumValue: ReactionOp.unknown)
   final ReactionOp op;
 
   final String emojiName;
@@ -1774,6 +1760,9 @@ class ReactionEvent extends Event {
 enum ReactionOp {
   add,
   remove,
+
+  /// A new, unrecognized operation.
+  unknown;
 }
 
 /// A Zulip event of type `heartbeat`: https://zulip.com/api/get-events#heartbeat
diff --git a/lib/api/model/events.g.dart b/lib/api/model/events.g.dart
index b6d46e49c..08b5b36ab 100644
--- a/lib/api/model/events.g.dart
+++ b/lib/api/model/events.g.dart
@@ -85,10 +85,10 @@ UserSettingsUpdateEvent _$UserSettingsUpdateEventFromJson(
   Map<String, dynamic> json,
 ) => UserSettingsUpdateEvent(
   id: (json['id'] as num).toInt(),
-  property: $enumDecodeNullable(
+  property: $enumDecode(
     _$UserSettingNameEnumMap,
     json['property'],
-    unknownValue: JsonKey.nullForUndefinedEnumValue,
+    unknownValue: UserSettingName.unknown,
   ),
   value: UserSettingsUpdateEvent._readValue(json, 'value'),
 );
@@ -110,6 +110,7 @@ const _$UserSettingNameEnumMap = {
   UserSettingName.emojiset: 'emojiset',
   UserSettingName.webInboxShowChannelFolders: 'web_inbox_show_channel_folders',
   UserSettingName.presenceEnabled: 'presence_enabled',
+  UserSettingName.unknown: 'unknown',
 };
 
 DeviceAddEvent _$DeviceAddEventFromJson(Map<String, dynamic> json) =>
@@ -564,10 +565,10 @@ ChannelUpdateEvent _$ChannelUpdateEventFromJson(Map<String, dynamic> json) =>
       id: (json['id'] as num).toInt(),
       streamId: (json['stream_id'] as num).toInt(),
       name: json['name'] as String,
-      property: $enumDecodeNullable(
-        _$ChannelPropertyNameEnumMap,
+      property: $enumDecode(
+        _$ChannelPropertyEnumMap,
         json['property'],
-        unknownValue: JsonKey.nullForUndefinedEnumValue,
+        unknownValue: ChannelProperty.unknown,
       ),
       value: ChannelUpdateEvent._readValue(json, 'value'),
       renderedDescription: json['rendered_description'] as String?,
@@ -583,30 +584,31 @@ Map<String, dynamic> _$ChannelUpdateEventToJson(ChannelUpdateEvent instance) =>
       'op': instance.op,
       'stream_id': instance.streamId,
       'name': instance.name,
-      'property': _$ChannelPropertyNameEnumMap[instance.property],
+      'property': _$ChannelPropertyEnumMap[instance.property]!,
       'value': instance.value,
       'rendered_description': instance.renderedDescription,
       'history_public_to_subscribers': instance.historyPublicToSubscribers,
       'is_web_public': instance.isWebPublic,
     };
 
-const _$ChannelPropertyNameEnumMap = {
-  ChannelPropertyName.name: 'name',
-  ChannelPropertyName.isArchived: 'is_archived',
-  ChannelPropertyName.description: 'description',
-  ChannelPropertyName.firstMessageId: 'first_message_id',
-  ChannelPropertyName.inviteOnly: 'invite_only',
-  ChannelPropertyName.messageRetentionDays: 'message_retention_days',
-  ChannelPropertyName.topicsPolicy: 'topics_policy',
-  ChannelPropertyName.channelPostPolicy: 'stream_post_policy',
-  ChannelPropertyName.folderId: 'folder_id',
-  ChannelPropertyName.canAddSubscribersGroup: 'can_add_subscribers_group',
-  ChannelPropertyName.canDeleteAnyMessageGroup: 'can_delete_any_message_group',
-  ChannelPropertyName.canDeleteOwnMessageGroup: 'can_delete_own_message_group',
-  ChannelPropertyName.canSendMessageGroup: 'can_send_message_group',
-  ChannelPropertyName.canSubscribeGroup: 'can_subscribe_group',
-  ChannelPropertyName.isRecentlyActive: 'is_recently_active',
-  ChannelPropertyName.streamWeeklyTraffic: 'stream_weekly_traffic',
+const _$ChannelPropertyEnumMap = {
+  ChannelProperty.name: 'name',
+  ChannelProperty.isArchived: 'is_archived',
+  ChannelProperty.description: 'description',
+  ChannelProperty.firstMessageId: 'first_message_id',
+  ChannelProperty.inviteOnly: 'invite_only',
+  ChannelProperty.messageRetentionDays: 'message_retention_days',
+  ChannelProperty.topicsPolicy: 'topics_policy',
+  ChannelProperty.channelPostPolicy: 'stream_post_policy',
+  ChannelProperty.folderId: 'folder_id',
+  ChannelProperty.canAddSubscribersGroup: 'can_add_subscribers_group',
+  ChannelProperty.canDeleteAnyMessageGroup: 'can_delete_any_message_group',
+  ChannelProperty.canDeleteOwnMessageGroup: 'can_delete_own_message_group',
+  ChannelProperty.canSendMessageGroup: 'can_send_message_group',
+  ChannelProperty.canSubscribeGroup: 'can_subscribe_group',
+  ChannelProperty.isRecentlyActive: 'is_recently_active',
+  ChannelProperty.streamWeeklyTraffic: 'stream_weekly_traffic',
+  ChannelProperty.unknown: 'unknown',
 };
 
 SubscriptionAddEvent _$SubscriptionAddEventFromJson(
@@ -1061,7 +1063,11 @@ const _$SubmessageTypeEnumMap = {
 
 TypingEvent _$TypingEventFromJson(Map<String, dynamic> json) => TypingEvent(
   id: (json['id'] as num).toInt(),
-  op: $enumDecode(_$TypingOpEnumMap, json['op']),
+  op: $enumDecode(
+    _$TypingOpEnumMap,
+    json['op'],
+    unknownValue: TypingOp.unknown,
+  ),
   messageType: const MessageTypeConverter().fromJson(
     json['message_type'] as String,
   ),
@@ -1085,7 +1091,11 @@ Map<String, dynamic> _$TypingEventToJson(TypingEvent instance) =>
       'topic': instance.topic,
     };
 
-const _$TypingOpEnumMap = {TypingOp.start: 'start', TypingOp.stop: 'stop'};
+const _$TypingOpEnumMap = {
+  TypingOp.start: 'start',
+  TypingOp.stop: 'stop',
+  TypingOp.unknown: 'unknown',
+};
 
 PresenceEvent _$PresenceEventFromJson(Map<String, dynamic> json) =>
     PresenceEvent(
@@ -1131,7 +1141,11 @@ const _$PresenceStatusEnumMap = {
 ReactionEvent _$ReactionEventFromJson(Map<String, dynamic> json) =>
     ReactionEvent(
       id: (json['id'] as num).toInt(),
-      op: $enumDecode(_$ReactionOpEnumMap, json['op']),
+      op: $enumDecode(
+        _$ReactionOpEnumMap,
+        json['op'],
+        unknownValue: ReactionOp.unknown,
+      ),
       emojiName: json['emoji_name'] as String,
       emojiCode: json['emoji_code'] as String,
       reactionType: $enumDecode(_$ReactionTypeEnumMap, json['reaction_type']),
@@ -1154,6 +1168,7 @@ Map<String, dynamic> _$ReactionEventToJson(ReactionEvent instance) =>
 const _$ReactionOpEnumMap = {
   ReactionOp.add: 'add',
   ReactionOp.remove: 'remove',
+  ReactionOp.unknown: 'unknown',
 };
 
 const _$ReactionTypeEnumMap = {
@@ -1167,8 +1182,3 @@ HeartbeatEvent _$HeartbeatEventFromJson(Map<String, dynamic> json) =>
 
 Map<String, dynamic> _$HeartbeatEventToJson(HeartbeatEvent instance) =>
     <String, dynamic>{'id': instance.id, 'type': instance.type};
-
-const _$MessageTypeEnumMap = {
-  MessageType.stream: 'stream',
-  MessageType.direct: 'direct',
-};
diff --git a/lib/api/model/initial_snapshot.dart b/lib/api/model/initial_snapshot.dart
index 1709d007b..e85a775cc 100644
--- a/lib/api/model/initial_snapshot.dart
+++ b/lib/api/model/initial_snapshot.dart
@@ -94,7 +94,7 @@ class InitialSnapshot {
   /// The policy for who can use wildcard mentions in large channels.
   ///
   /// Search for "realm_wildcard_mention_policy" in https://zulip.com/api/register-queue.
-  final RealmWildcardMentionPolicy realmWildcardMentionPolicy;
+  final RealmWildcardMentionPolicy? realmWildcardMentionPolicy; // TODO(server-10) remove
 
   @JsonKey(unknownEnumValue: RealmTopicsPolicy.unknown)
   final RealmTopicsPolicy? realmTopicsPolicy; // TODO(server-11)
@@ -237,7 +237,12 @@ enum RealmWildcardMentionPolicy {
   fullMembers(apiValue: 3),
   admins(apiValue: 5),
   nobody(apiValue: 6),
-  moderators(apiValue: 7);
+  moderators(apiValue: 7),
+
+  // We don't accept an unknown value. `realm_wildcard_mention_policy` is
+  // deprecated in server-10, making future additions to this enum unlikely.
+  // unknown(apiValue: null),
+  ;
 
   const RealmWildcardMentionPolicy({required this.apiValue});
 
@@ -252,7 +257,12 @@ enum RealmDeleteOwnMessagePolicy {
   admins(apiValue: 2),
   fullMembers(apiValue: 3),
   moderators(apiValue: 4),
-  everyone(apiValue: 5);
+  everyone(apiValue: 5),
+
+  // We don't accept an unknown value. `realm_delete_own_message_policy` is
+  // removed in server-10, making future additions to this enum impossible.
+  // unknown(apiValue: -100),
+  ;
 
   const RealmDeleteOwnMessagePolicy({required this.apiValue});
 
diff --git a/lib/api/model/initial_snapshot.g.dart b/lib/api/model/initial_snapshot.g.dart
index 8ecc74a76..55ccb43d8 100644
--- a/lib/api/model/initial_snapshot.g.dart
+++ b/lib/api/model/initial_snapshot.g.dart
@@ -107,7 +107,7 @@ InitialSnapshot _$InitialSnapshotFromJson(
     _$RealmDeleteOwnMessagePolicyEnumMap,
     json['realm_delete_own_message_policy'],
   ),
-  realmWildcardMentionPolicy: $enumDecode(
+  realmWildcardMentionPolicy: $enumDecodeNullable(
     _$RealmWildcardMentionPolicyEnumMap,
     json['realm_wildcard_mention_policy'],
   ),
diff --git a/lib/api/model/model.dart b/lib/api/model/model.dart
index 271985a58..365ad42dd 100644
--- a/lib/api/model/model.dart
+++ b/lib/api/model/model.dart
@@ -341,13 +341,20 @@ enum UserSettingName {
   emojiset,
   webInboxShowChannelFolders,
   presenceEnabled,
+  // TODO: add more as needed
+
+  /// A user setting (name) that:
+  ///   - The server sends, but we currently don't support.
+  ///   - The server may start sending in the future.
+  unknown,
   ;
 
-  /// Get a [UserSettingName] from a raw, snake-case string we recognize, else null.
+  /// Get a [UserSettingName] from a raw, snake-case string we recognize,
+  /// else [UserSettingName.unknown].
   ///
   /// Example:
   ///   'display_emoji_reaction_users' -> UserSettingName.displayEmojiReactionUsers
-  static UserSettingName? fromRawString(String raw) => _byRawString[raw];
+  static UserSettingName fromRawString(String raw) => _byRawString[raw] ?? unknown;
 
   // _$…EnumMap is thanks to `alwaysCreate: true` and `fieldRename: FieldRename.snake`
   static final _byRawString = _$UserSettingNameEnumMap
@@ -368,6 +375,12 @@ enum TwentyFourHourTimeMode {
   // TODO(server-future) Write down what server N starts sending null;
   //   adjust the comment; leave a TODO(server-N) to delete the comment
   localeDefault(apiValue: null),
+
+  // We can't have an unknown value because all values permitted by the
+  // server API (true, false, and null) are represented above.
+  // If the server ever sends a different kind of value, that would indicate
+  // a change to the API and we should update this model accordingly.
+  // unknown(apiValue: null),
   ;
 
   const TwentyFourHourTimeMode({required this.apiValue});
@@ -394,7 +407,7 @@ enum Emojiset {
   text,
   unknown;
 
-  /// Get an [Emojiset] from a raw string. Throws if the string is unrecognized.
+  /// Get an [Emojiset] from a raw string we recognize, else [Emojiset.unknown].
   ///
   /// Example:
   ///   'google-blob' -> Emojiset.googleBlob
@@ -613,7 +626,13 @@ class PerUserPresence {
 @JsonEnum(fieldRename: FieldRename.snake, alwaysCreate: true)
 enum PresenceStatus {
   active,
-  idle;
+  idle,
+
+  // We don't accept an unknown value. The [PerClientPresence] format is
+  // considered legacy and is expected to be removed in a future server release,
+  // making additions to this enum unlikely.
+  // unknown,
+  ;
 
   String toJson() => _$PresenceStatusEnumMap[this]!;
 }
@@ -651,7 +670,7 @@ class SavedSnippet {
 @JsonSerializable(fieldRename: FieldRename.snake)
 class ZulipStream {
   // When adding a field to this class:
-  //  * Add it to [ChannelPropertyName] too, or add a comment there explaining
+  //  * Add it to [ChannelProperty] too, or add a comment there explaining
   //    why there isn't a corresponding value in that enum.
   //  * If the field can never change for a given Zulip stream, mark it final.
   //    Otherwise, make sure it gets updated on [ChannelUpdateEvent].
@@ -765,7 +784,7 @@ class ZulipStream {
 /// we switch exhaustively on a value of this type
 /// to ensure that every property in [ZulipStream] responds to the event.
 @JsonEnum(fieldRename: FieldRename.snake, alwaysCreate: true)
-enum ChannelPropertyName {
+enum ChannelProperty {
   // streamId is immutable
   name,
   isArchived,
@@ -787,16 +806,24 @@ enum ChannelPropertyName {
   canSendMessageGroup,
   canSubscribeGroup,
   isRecentlyActive,
-  streamWeeklyTraffic;
+  streamWeeklyTraffic,
+  // TODO: add more as needed
+
+  /// A channel property name that:
+  ///   - The server sends, but we currently don't support.
+  ///   - The server may start sending in the future.
+  unknown,
+  ;
 
-  /// Get a [ChannelPropertyName] from a raw, snake-case string we recognize, else null.
+  /// Get a [ChannelProperty] from a raw, snake-case string we recognize,
+  /// else [ChannelProperty.unknown].
   ///
   /// Example:
-  ///   'invite_only' -> ChannelPropertyName.inviteOnly
-  static ChannelPropertyName? fromRawString(String raw) => _byRawString[raw];
+  ///   'invite_only' -> ChannelProperty.inviteOnly
+  static ChannelProperty fromRawString(String raw) => _byRawString[raw] ?? unknown;
 
   // _$…EnumMap is thanks to `alwaysCreate: true` and `fieldRename: FieldRename.snake`
-  static final _byRawString = _$ChannelPropertyNameEnumMap
+  static final _byRawString = _$ChannelPropertyEnumMap
     .map((key, value) => MapEntry(value, key));
 }
 
@@ -1221,7 +1248,10 @@ sealed class Message<T extends Conversation> extends MessageBase<T> {
   @JsonKey(name: 'submessages', readValue: _readPoll, fromJson: Poll.fromJson, toJson: Poll.toJson)
   Poll? poll;
 
-  String get type;
+  // The server never actually sends "channel" or "direct" here yet
+  // (it's "stream" or "private" instead), but we accept both the old
+  // and new forms for forward-compatibility.
+  MessageType get type;
 
   // final List<TopicLink> topicLinks; // TODO handle
   // final string type; // handled by runtime type of object
@@ -1280,15 +1310,50 @@ sealed class Message<T extends Conversation> extends MessageBase<T> {
   // TODO(dart): This has to be a static method, because factories/constructors
   //   do not support type parameters: https://github.com/dart-lang/language/issues/647
   static Message fromJson(Map<String, dynamic> json) {
-    final type = json['type'] as String;
-    if (type == 'stream') return StreamMessage.fromJson(json);
-    if (type == 'private') return DmMessage.fromJson(json);
-    throw Exception("Message.fromJson: unexpected message type $type");
+    return switch (MessageType.fromJson(json['type'] as String)) {
+      .channel => StreamMessage.fromJson(json),
+      .direct => DmMessage.fromJson(json),
+    };
   }
 
   Map<String, dynamic> toJson();
 }
 
+/// As in [Message.type], [DeleteMessageEvent.messageType],
+/// [UpdateMessageFlagsMessageDetail.type], or [TypingEvent.messageType].
+@JsonEnum(alwaysCreate: true)
+enum MessageType {
+  channel,
+  direct,
+
+  // We don't accept an unknown message type because we generally cannot decide
+  // how to interpret such data. In particular, when a message with an unknown
+  // type is received from the server, we cannot determine which message model
+  // to instantiate: either [StreamMessage] or [DmMessage]. See [Message.fromJson].
+  // unknown,
+  ;
+
+  factory fromJson(String json) {
+    if (json == 'stream') json = 'channel'; // TODO(server-future)
+    if (json == 'private') json = 'direct'; // TODO(server-future)
+    return $enumDecode(_$MessageTypeEnumMap, json);
+  }
+}
+
+class MessageTypeConverter extends JsonConverter<MessageType, String> {
+  const MessageTypeConverter();
+
+  @override
+  MessageType fromJson(String json) {
+    return MessageType.fromJson(json);
+  }
+
+  @override
+  String toJson(MessageType object) {
+    return _$MessageTypeEnumMap[object]!;
+  }
+}
+
 /// https://zulip.com/api/update-message-flags#available-flags
 @JsonEnum(fieldRename: FieldRename.snake, alwaysCreate: true)
 enum MessageFlag {
@@ -1339,7 +1404,7 @@ enum MessageFlag {
 class StreamMessage extends Message<StreamConversation> {
   @override
   @JsonKey(includeToJson: true)
-  String get type => 'stream';
+  MessageType get type => .channel;
 
   @JsonKey(includeToJson: true)
   int get streamId => conversation.streamId;
@@ -1393,7 +1458,7 @@ class StreamMessage extends Message<StreamConversation> {
 class DmMessage extends Message<DmConversation> {
   @override
   @JsonKey(includeToJson: true)
-  String get type => 'private';
+  MessageType get type => .direct;
 
   /// The user IDs of all users in the thread, sorted numerically, as in
   /// `display_recipient` from the server.
diff --git a/lib/api/model/model.g.dart b/lib/api/model/model.g.dart
index 4e71852af..bf015ca40 100644
--- a/lib/api/model/model.g.dart
+++ b/lib/api/model/model.g.dart
@@ -504,7 +504,7 @@ Map<String, dynamic> _$StreamMessageToJson(StreamMessage instance) =>
       'flags': instance.flags,
       'match_content': instance.matchContent,
       'match_subject': instance.matchTopic,
-      'type': instance.type,
+      'type': _$MessageTypeEnumMap[instance.type]!,
       'stream_id': instance.streamId,
       'subject': instance.topic,
       'display_recipient': instance.displayRecipient,
@@ -516,6 +516,11 @@ const _$MessageEditStateEnumMap = {
   MessageEditState.moved: 'moved',
 };
 
+const _$MessageTypeEnumMap = {
+  MessageType.channel: 'channel',
+  MessageType.direct: 'direct',
+};
+
 DmMessage _$DmMessageFromJson(Map<String, dynamic> json) => DmMessage(
   client: json['client'] as String,
   content: json['content'] as String,
@@ -558,7 +563,7 @@ Map<String, dynamic> _$DmMessageToJson(DmMessage instance) => <String, dynamic>{
   'flags': instance.flags,
   'match_content': instance.matchContent,
   'match_subject': instance.matchTopic,
-  'type': instance.type,
+  'type': _$MessageTypeEnumMap[instance.type]!,
   'display_recipient': DmMessage._allRecipientIdsToJson(
     instance.allRecipientIds,
   ),
@@ -571,6 +576,7 @@ const _$UserSettingNameEnumMap = {
   UserSettingName.emojiset: 'emojiset',
   UserSettingName.webInboxShowChannelFolders: 'web_inbox_show_channel_folders',
   UserSettingName.presenceEnabled: 'presence_enabled',
+  UserSettingName.unknown: 'unknown',
 };
 
 const _$EmojisetEnumMap = {
@@ -586,23 +592,24 @@ const _$PresenceStatusEnumMap = {
   PresenceStatus.idle: 'idle',
 };
 
-const _$ChannelPropertyNameEnumMap = {
-  ChannelPropertyName.name: 'name',
-  ChannelPropertyName.isArchived: 'is_archived',
-  ChannelPropertyName.description: 'description',
-  ChannelPropertyName.firstMessageId: 'first_message_id',
-  ChannelPropertyName.inviteOnly: 'invite_only',
-  ChannelPropertyName.messageRetentionDays: 'message_retention_days',
-  ChannelPropertyName.topicsPolicy: 'topics_policy',
-  ChannelPropertyName.channelPostPolicy: 'stream_post_policy',
-  ChannelPropertyName.folderId: 'folder_id',
-  ChannelPropertyName.canAddSubscribersGroup: 'can_add_subscribers_group',
-  ChannelPropertyName.canDeleteAnyMessageGroup: 'can_delete_any_message_group',
-  ChannelPropertyName.canDeleteOwnMessageGroup: 'can_delete_own_message_group',
-  ChannelPropertyName.canSendMessageGroup: 'can_send_message_group',
-  ChannelPropertyName.canSubscribeGroup: 'can_subscribe_group',
-  ChannelPropertyName.isRecentlyActive: 'is_recently_active',
-  ChannelPropertyName.streamWeeklyTraffic: 'stream_weekly_traffic',
+const _$ChannelPropertyEnumMap = {
+  ChannelProperty.name: 'name',
+  ChannelProperty.isArchived: 'is_archived',
+  ChannelProperty.description: 'description',
+  ChannelProperty.firstMessageId: 'first_message_id',
+  ChannelProperty.inviteOnly: 'invite_only',
+  ChannelProperty.messageRetentionDays: 'message_retention_days',
+  ChannelProperty.topicsPolicy: 'topics_policy',
+  ChannelProperty.channelPostPolicy: 'stream_post_policy',
+  ChannelProperty.folderId: 'folder_id',
+  ChannelProperty.canAddSubscribersGroup: 'can_add_subscribers_group',
+  ChannelProperty.canDeleteAnyMessageGroup: 'can_delete_any_message_group',
+  ChannelProperty.canDeleteOwnMessageGroup: 'can_delete_own_message_group',
+  ChannelProperty.canSendMessageGroup: 'can_send_message_group',
+  ChannelProperty.canSubscribeGroup: 'can_subscribe_group',
+  ChannelProperty.isRecentlyActive: 'is_recently_active',
+  ChannelProperty.streamWeeklyTraffic: 'stream_weekly_traffic',
+  ChannelProperty.unknown: 'unknown',
 };
 
 const _$SubscriptionPropertyEnumMap = {
diff --git a/lib/api/route/messages.dart b/lib/api/route/messages.dart
index 6724b6236..8a83caf90 100644
--- a/lib/api/route/messages.dart
+++ b/lib/api/route/messages.dart
@@ -134,12 +134,13 @@ Future<SendMessageResult> sendMessage(
   String? localId,
   bool? readBySender,
 }) {
+  final supportsTypeChannel = connection.zulipFeatureLevel! >= 248; // TODO(server-9)
   final supportsTypeDirect = connection.zulipFeatureLevel! >= 174; // TODO(server-7)
   final supportsReadBySender = connection.zulipFeatureLevel! >= 236; // TODO(server-8)
   return connection.post('sendMessage', SendMessageResult.fromJson, 'messages', {
     ...(switch (destination) {
       StreamDestination() => {
-        'type': RawParameter('stream'),
+        'type': supportsTypeChannel ? RawParameter('channel') : RawParameter('stream'),
         'to': destination.streamId,
         'topic': RawParameter(destination.topic.apiName),
       },
diff --git a/lib/api/route/settings.dart b/lib/api/route/settings.dart
index 141994cb2..858fa9af4 100644
--- a/lib/api/route/settings.dart
+++ b/lib/api/route/settings.dart
@@ -11,19 +11,21 @@ Future<void> updateSettings(ApiConnection connection, {
     final valueRaw = entry.value;
     final Object? value;
     switch (name) {
-      case UserSettingName.twentyFourHourTime:
+      case .twentyFourHourTime:
         final mode = (valueRaw as TwentyFourHourTimeMode);
         // TODO(server-future) allow localeDefault for servers that support it
-        assert(mode != TwentyFourHourTimeMode.localeDefault);
+        assert(mode != .localeDefault);
         value = mode.toJson();
-      case UserSettingName.starredMessageCounts:
-      case UserSettingName.displayEmojiReactionUsers:
+      case .starredMessageCounts:
+      case .displayEmojiReactionUsers:
         value = valueRaw as bool;
-      case UserSettingName.emojiset:
+      case .emojiset:
         value = RawParameter((valueRaw as Emojiset).toJson());
-      case UserSettingName.webInboxShowChannelFolders:
-      case UserSettingName.presenceEnabled:
+      case .webInboxShowChannelFolders:
+      case .presenceEnabled:
         value = valueRaw as bool;
+      case .unknown:
+        continue;
     }
     params[name.toJson()] = value;
   }
diff --git a/lib/api/route/typing.dart b/lib/api/route/typing.dart
index 8e2e5dae6..81899d867 100644
--- a/lib/api/route/typing.dart
+++ b/lib/api/route/typing.dart
@@ -7,7 +7,11 @@ import 'messages.dart';
 Future<void> setTypingStatus(ApiConnection connection, {
   required TypingOp op,
   required MessageDestination destination,
-}) {
+}) async {
+  if (op == .unknown) {
+    assert(false, 'TypingOp.unknown is not supported when setting typing status.');
+    return;
+  }
   switch (destination) {
     case StreamDestination():
       final supportsTypeChannel = connection.zulipFeatureLevel! >= 248; // TODO(server-9)
diff --git a/lib/model/channel.dart b/lib/model/channel.dart
index 4f994cede..bd40ba643 100644
--- a/lib/model/channel.dart
+++ b/lib/model/channel.dart
@@ -236,7 +236,7 @@ mixin ChannelStore on UserStore {
     if (channel is Subscription) return true;
     // Here web calls has_metadata_access... but that always returns true,
     // as its comment says.
-    if (selfUser.role == UserRole.guest) return false;
+    if (selfUser.role == .guest) return false;
     if (!channel.inviteOnly) return true;
     return _selfHasContentAccessViaGroupPermissions(channel);
   }
@@ -288,14 +288,14 @@ mixin ChannelStore on UserStore {
     switch (inChannel.channelPostPolicy!) {
       case ChannelPostPolicy.any:             return true;
       case ChannelPostPolicy.fullMembers:     {
-        if (!role.isAtLeast(UserRole.member)) return false;
-        if (role == UserRole.member) {
+        if (!role.isAtLeast(.member)) return false;
+        if (role == .member) {
           return selfHasPassedWaitingPeriod(byDate: atDate);
         }
         return true;
       }
-      case ChannelPostPolicy.moderators:      return role.isAtLeast(UserRole.moderator);
-      case ChannelPostPolicy.administrators:  return role.isAtLeast(UserRole.administrator);
+      case ChannelPostPolicy.moderators:      return role.isAtLeast(.moderator);
+      case ChannelPostPolicy.administrators:  return role.isAtLeast(.administrator);
       case ChannelPostPolicy.unknown:         return true;
     }
   }
@@ -542,48 +542,51 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
           stream.isWebPublic = event.isWebPublic!;
         }
 
-        if (event.property == null) {
+        if (event.property == .unknown) {
           // unrecognized property; do nothing
           return;
         }
-        switch (event.property!) {
-          case ChannelPropertyName.name:
+        switch (event.property) {
+          case .name:
             final streamName = stream.name;
             assert(streamName == event.name);
             assert(identical(streams[stream.streamId], streamsByName[streamName]));
             stream.name = event.value as String;
             streamsByName.remove(streamName);
             streamsByName[stream.name] = stream;
-          case ChannelPropertyName.isArchived:
+          case .isArchived:
             stream.isArchived = event.value as bool;
-          case ChannelPropertyName.description:
+          case .description:
             stream.description = event.value as String;
-          case ChannelPropertyName.firstMessageId:
+          case .firstMessageId:
             stream.firstMessageId = event.value as int?;
-          case ChannelPropertyName.inviteOnly:
+          case .inviteOnly:
             stream.inviteOnly = event.value as bool;
-          case ChannelPropertyName.messageRetentionDays:
+          case .messageRetentionDays:
             stream.messageRetentionDays = event.value as int?;
-          case ChannelPropertyName.topicsPolicy:
+          case .topicsPolicy:
             stream.topicsPolicy = event.value as ChannelTopicsPolicy;
-          case ChannelPropertyName.channelPostPolicy:
+          case .channelPostPolicy:
             stream.channelPostPolicy = event.value as ChannelPostPolicy;
-          case ChannelPropertyName.folderId:
+          case .folderId:
             stream.folderId = event.value as int?;
-          case ChannelPropertyName.canAddSubscribersGroup:
+          case .canAddSubscribersGroup:
             stream.canAddSubscribersGroup = event.value as GroupSettingValue;
-          case ChannelPropertyName.canDeleteAnyMessageGroup:
+          case .canDeleteAnyMessageGroup:
             stream.canDeleteAnyMessageGroup = event.value as GroupSettingValue;
-          case ChannelPropertyName.canDeleteOwnMessageGroup:
+          case .canDeleteOwnMessageGroup:
             stream.canDeleteOwnMessageGroup = event.value as GroupSettingValue;
-          case ChannelPropertyName.canSendMessageGroup:
+          case .canSendMessageGroup:
             stream.canSendMessageGroup = event.value as GroupSettingValue;
-          case ChannelPropertyName.canSubscribeGroup:
+          case .canSubscribeGroup:
             stream.canSubscribeGroup = event.value as GroupSettingValue;
-          case ChannelPropertyName.isRecentlyActive:
+          case .isRecentlyActive:
             stream.isRecentlyActive = event.value as bool;
-          case ChannelPropertyName.streamWeeklyTraffic:
+          case .streamWeeklyTraffic:
             stream.streamWeeklyTraffic = event.value as int?;
+          case .unknown:
+            // Shouldn't reach here because of the early return.
+            assert(false);
         }
     }
   }
diff --git a/lib/model/emoji.dart b/lib/model/emoji.dart
index 7338c50c8..959ab356d 100644
--- a/lib/model/emoji.dart
+++ b/lib/model/emoji.dart
@@ -20,7 +20,7 @@ sealed class EmojiDisplay {
 
   EmojiDisplay resolve(UserSettings userSettings) {
     if (this is TextEmojiDisplay) return this;
-    if (userSettings.emojiset == Emojiset.text) {
+    if (userSettings.emojiset == .text) {
       return TextEmojiDisplay(emojiName: emojiName);
     }
     return this;
diff --git a/lib/model/message.dart b/lib/model/message.dart
index 17d4775fb..a375b2a44 100644
--- a/lib/model/message.dart
+++ b/lib/model/message.dart
@@ -7,7 +7,6 @@ import 'package:flutter/foundation.dart';
 
 import '../api/exception.dart';
 import '../api/model/events.dart';
-import '../api/model/initial_snapshot.dart';
 import '../api/model/model.dart';
 import '../api/route/messages.dart';
 import '../log.dart';
@@ -185,21 +184,21 @@ mixin MessageStore on ChannelStore {
     // but pre-291 servers shouldn't be giving us an unknown role.)
 
     switch (realmDeleteOwnMessagePolicy!) {
-      case RealmDeleteOwnMessagePolicy.everyone:
+      case .everyone:
         return true;
-      case RealmDeleteOwnMessagePolicy.members:
-        return role.isAtLeast(UserRole.member);
-      case RealmDeleteOwnMessagePolicy.fullMembers: {
-        if (!role.isAtLeast(UserRole.member)) return false;
-        if (role == UserRole.member) {
+      case .members:
+        return role.isAtLeast(.member);
+      case .fullMembers: {
+        if (!role.isAtLeast(.member)) return false;
+        if (role == .member) {
           return selfHasPassedWaitingPeriod(byDate: atDate);
         }
         return true;
       }
-      case RealmDeleteOwnMessagePolicy.moderators:
-        return role.isAtLeast(UserRole.moderator);
-      case RealmDeleteOwnMessagePolicy.admins:
-        return role.isAtLeast(UserRole.administrator);
+      case .moderators:
+        return role.isAtLeast(.moderator);
+      case .admins:
+        return role.isAtLeast(.administrator);
     }
   }
 }
@@ -832,18 +831,20 @@ class MessageStoreImpl extends HasChannelStore with MessageStore, _OutboxMessage
   }
 
   void handleReactionEvent(ReactionEvent event) {
+    if (event.op == .unknown) return;
+
     final message = messages[event.messageId];
     if (message == null) return;
 
     switch (event.op) {
-      case ReactionOp.add:
+      case .add:
         (message.reactions ??= Reactions([])).add(Reaction(
           emojiName: event.emojiName,
           emojiCode: event.emojiCode,
           reactionType: event.reactionType,
           userId: event.userId,
         ));
-      case ReactionOp.remove:
+      case .remove:
         if (message.reactions == null) { // TODO(log)
           return;
         }
@@ -852,6 +853,8 @@ class MessageStoreImpl extends HasChannelStore with MessageStore, _OutboxMessage
           emojiCode: event.emojiCode,
           userId: event.userId,
         );
+      case .unknown:
+        // Shouldn't reach here because of the early return.
     }
     _notifyMessageListViewsForOneMessage(event.messageId);
   }
diff --git a/lib/model/narrow.dart b/lib/model/narrow.dart
index 8042dbee5..aa47b5328 100644
--- a/lib/model/narrow.dart
+++ b/lib/model/narrow.dart
@@ -241,7 +241,7 @@ class DmNarrow extends Narrow implements SendableNarrow {
     UpdateMessageFlagsMessageDetail detail, {
     required int selfUserId,
   }) {
-    assert(detail.type == MessageType.direct);
+    assert(detail.type == .direct);
     return DmNarrow.withOtherUsers(detail.userIds!, selfUserId: selfUserId);
   }
 
diff --git a/lib/model/presence.dart b/lib/model/presence.dart
index 882f12031..8772c33c2 100644
--- a/lib/model/presence.dart
+++ b/lib/model/presence.dart
@@ -76,14 +76,14 @@ class Presence extends HasRealmStore with ChangeNotifier {
         //   when the user closes the app completely.
         result = await updatePresence(connection,
           pingOnly: pingOnly,
-          status: PresenceStatus.idle,
+          status: .idle,
           newUserInput: false);
       case AppLifecycleState.resumed:
         // > […] the default running mode for a running application that has
         // > input focus and is visible.
         result = await updatePresence(connection,
           pingOnly: pingOnly,
-          status: PresenceStatus.active,
+          status: .active,
           newUserInput: true);
       case AppLifecycleState.inactive:
         // > At least one view of the application is visible, but none have
@@ -92,7 +92,7 @@ class Presence extends HasRealmStore with ChangeNotifier {
         // to upload.
         result = await updatePresence(connection,
           pingOnly: pingOnly,
-          status: PresenceStatus.active,
+          status: .active,
           newUserInput: false);
     }
     if (!pingOnly) {
@@ -141,12 +141,12 @@ class Presence extends HasRealmStore with ChangeNotifier {
     final PerUserPresence(:activeTimestamp, :idleTimestamp) = perUserPresence;
 
     if (now - activeTimestamp <= serverPresenceOfflineThresholdSeconds) {
-      return PresenceStatus.active;
+      return .active;
     } else if (now - idleTimestamp <= serverPresenceOfflineThresholdSeconds) {
       // The API doc is kind of confusing, but this seems correct:
       //   https://chat.zulip.org/#narrow/channel/378-api-design/topic/presence.3A.20.22potentially.20present.22.3F/near/2202431
       // TODO clarify that API doc
-      return PresenceStatus.idle;
+      return .idle;
     } else {
       return null;
     }
diff --git a/lib/model/realm.dart b/lib/model/realm.dart
index cffb3095f..2691b79ef 100644
--- a/lib/model/realm.dart
+++ b/lib/model/realm.dart
@@ -73,7 +73,7 @@ mixin RealmStore on PerAccountStoreBase, UserGroupStore {
   // Realm settings previously found in realm/update_dict events,
   // but now deprecated.
 
-  RealmWildcardMentionPolicy get realmWildcardMentionPolicy; // TODO(server-10) remove
+  RealmWildcardMentionPolicy? get realmWildcardMentionPolicy; // TODO(server-10) remove
   RealmDeleteOwnMessagePolicy? get realmDeleteOwnMessagePolicy; // TODO(server-10) remove
 
   //|//////////////////////////////
@@ -212,7 +212,7 @@ mixin ProxyRealmStore on RealmStore {
   @override
   int get realmWaitingPeriodThreshold => realmStore.realmWaitingPeriodThreshold;
   @override
-  RealmWildcardMentionPolicy get realmWildcardMentionPolicy => realmStore.realmWildcardMentionPolicy;
+  RealmWildcardMentionPolicy? get realmWildcardMentionPolicy => realmStore.realmWildcardMentionPolicy;
   @override
   RealmDeleteOwnMessagePolicy? get realmDeleteOwnMessagePolicy => realmStore.realmDeleteOwnMessagePolicy;
   @override
@@ -317,7 +317,7 @@ class RealmStoreImpl extends HasUserGroupStore with RealmStore {
 
     final config = _groupSettingConfig(type, name);
 
-    if (_selfUserRole == UserRole.guest && !config.allowEveryoneGroup) {
+    if (_selfUserRole == .guest && !config.allowEveryoneGroup) {
       return false;
     }
 
@@ -348,7 +348,7 @@ class RealmStoreImpl extends HasUserGroupStore with RealmStore {
       case SystemGroupName.everyone:
         return true;
       case SystemGroupName.members:
-        return _selfUserRole.isAtLeast(UserRole.member);
+        return _selfUserRole.isAtLeast(.member);
       case SystemGroupName.fullMembers:
         // There aren't any permissions where this is the default, and we
         // probably won't add any. So for now we skip the complication of
@@ -356,13 +356,13 @@ class RealmStoreImpl extends HasUserGroupStore with RealmStore {
         assert(() {
           throw UnimplementedError();
         }());
-        return _selfUserRole.isAtLeast(UserRole.member);
+        return _selfUserRole.isAtLeast(.member);
       case SystemGroupName.moderators:
-        return _selfUserRole.isAtLeast(UserRole.moderator);
+        return _selfUserRole.isAtLeast(.moderator);
       case SystemGroupName.administrators:
-        return _selfUserRole.isAtLeast(UserRole.administrator);
+        return _selfUserRole.isAtLeast(.administrator);
       case SystemGroupName.owners:
-        return _selfUserRole.isAtLeast(UserRole.owner);
+        return _selfUserRole.isAtLeast(.owner);
       case SystemGroupName.nobody:
         return false;
     }
@@ -449,7 +449,7 @@ class RealmStoreImpl extends HasUserGroupStore with RealmStore {
   final int realmWaitingPeriodThreshold;
 
   @override
-  final RealmWildcardMentionPolicy realmWildcardMentionPolicy;
+  final RealmWildcardMentionPolicy? realmWildcardMentionPolicy;
   @override
   final RealmDeleteOwnMessagePolicy? realmDeleteOwnMessagePolicy;
 
diff --git a/lib/model/recent_senders.dart b/lib/model/recent_senders.dart
index 274d70fd0..2e2d4b617 100644
--- a/lib/model/recent_senders.dart
+++ b/lib/model/recent_senders.dart
@@ -87,7 +87,7 @@ class RecentSenders {
   }
 
   void handleDeleteMessageEvent(DeleteMessageEvent event, Map<int, Message> cachedMessages) {
-    if (event.messageType != MessageType.stream) return;
+    if (event.messageType != .channel) return;
 
     final messagesByUser = <int, List<int>>{};
     for (final id in event.messageIds) {
diff --git a/lib/model/store.dart b/lib/model/store.dart
index 5b554bf64..8508e1248 100644
--- a/lib/model/store.dart
+++ b/lib/model/store.dart
@@ -903,24 +903,27 @@ class PerAccountStore extends PerAccountStoreBase with
         // We don't yet store this data, so there's nothing to update.
 
       case UserSettingsUpdateEvent():
-        assert(debugLog("server event: user_settings/update ${event.property?.name ?? '[unrecognized]'}"));
-        if (event.property == null) {
+        assert(debugLog("server event: user_settings/update ${event.property.name}"));
+        if (event.property == .unknown) {
           // unrecognized setting; do nothing
           return;
         }
-        switch (event.property!) {
-          case UserSettingName.twentyFourHourTime:
+        switch (event.property) {
+          case .twentyFourHourTime:
             userSettings.twentyFourHourTime         = event.value as TwentyFourHourTimeMode;
-          case UserSettingName.starredMessageCounts:
+          case .starredMessageCounts:
             userSettings.starredMessageCounts       = event.value as bool;
-          case UserSettingName.displayEmojiReactionUsers:
+          case .displayEmojiReactionUsers:
             userSettings.displayEmojiReactionUsers  = event.value as bool;
-          case UserSettingName.emojiset:
+          case .emojiset:
             userSettings.emojiset                   = event.value as Emojiset;
-          case UserSettingName.webInboxShowChannelFolders:
+          case .webInboxShowChannelFolders:
             userSettings.webInboxShowChannelFolders = event.value as bool;
-          case UserSettingName.presenceEnabled:
+          case .presenceEnabled:
             userSettings.presenceEnabled            = event.value as bool;
+          case .unknown:
+            // Shouldn't reach here because of the early return.
+            assert(false);
         }
         notifyListeners();
 
diff --git a/lib/model/typing_status.dart b/lib/model/typing_status.dart
index fdb63339b..f8b8f22a3 100644
--- a/lib/model/typing_status.dart
+++ b/lib/model/typing_status.dart
@@ -62,18 +62,22 @@ class TypingStatus extends HasRealmStore with ChangeNotifier {
   }
 
   void handleTypingEvent(TypingEvent event) {
+    if (event.op == .unknown) return;
+
     SendableNarrow narrow = switch (event.messageType) {
-      MessageType.direct => DmNarrow(
+      .direct => DmNarrow(
         allRecipientIds: event.recipientIds!, selfUserId: selfUserId),
-      MessageType.stream => TopicNarrow(event.streamId!, event.topic!),
+      .channel => TopicNarrow(event.streamId!, event.topic!),
     };
 
     bool hasUpdate = false;
     switch (event.op) {
-      case TypingOp.start:
+      case .start:
         hasUpdate = _addTypist(narrow, event.senderId);
-      case TypingOp.stop:
+      case .stop:
         hasUpdate = _removeTypist(narrow, event.senderId);
+      case .unknown:
+        // Shouldn't reach here because of the early return.
     }
 
     if (hasUpdate) {
@@ -176,7 +180,7 @@ class TypingNotifier extends HasRealmStore {
 
     unawaited(setTypingStatus(
       connection,
-      op: TypingOp.start,
+      op: .start,
       destination: _currentDestination!.destination));
   }
 
@@ -190,7 +194,7 @@ class TypingNotifier extends HasRealmStore {
 
     unawaited(setTypingStatus(
       connection,
-      op: TypingOp.stop,
+      op: .stop,
       destination: destination.destination));
   }
 
diff --git a/lib/model/unreads.dart b/lib/model/unreads.dart
index a45f53f50..5e8096155 100644
--- a/lib/model/unreads.dart
+++ b/lib/model/unreads.dart
@@ -412,13 +412,13 @@ class Unreads extends PerAccountStoreBase with ChangeNotifier {
   void handleDeleteMessageEvent(DeleteMessageEvent event) {
     mentions.removeAll(event.messageIds);
     switch (event.messageType) {
-      case MessageType.stream:
+      case .channel:
         // All the messages are in [event.streamId] and [event.topic],
         // so we can be more efficient than _removeAllInStreamsAndDms.
         final streamId = event.streamId!;
         final topic = event.topic!;
         _removeAllInStreamTopic(Set.of(event.messageIds), streamId, topic);
-      case MessageType.direct:
+      case .direct:
         _removeAllInStreamsAndDms(event.messageIds, expectOnlyDms: true);
     }
     for (final messageId in event.messageIds) {
@@ -490,13 +490,13 @@ class Unreads extends PerAccountStoreBase with ChangeNotifier {
                 mentions.add(messageId);
               }
               switch (detail.type) {
-                case MessageType.stream:
+                case .channel:
                   final UpdateMessageFlagsMessageDetail(:streamId, :topic) = detail;
                   locatorMap[messageId] = TopicNarrow(streamId!, topic!);
                   final topics = (newlyUnreadInStreams[streamId] ??= makeTopicKeyedMap());
                   final messageIds = (topics[topic] ??= QueueList());
                   messageIds.add(messageId);
-                case MessageType.direct:
+                case .direct:
                   final narrow = DmNarrow.ofUpdateMessageFlagsMessageDetail(selfUserId: selfUserId,
                     detail);
                   locatorMap[messageId] = narrow;
diff --git a/lib/widgets/content.dart b/lib/widgets/content.dart
index a6dcc5fe9..be3082c85 100644
--- a/lib/widgets/content.dart
+++ b/lib/widgets/content.dart
@@ -1439,9 +1439,9 @@ class GlobalTime extends StatelessWidget {
     //   see zulip:web/styles/rendered_markdown.css .
     // TODO(i18n): localize; see plan with ffi in #45
     final format = switch (twentyFourHourTimeMode) {
-      TwentyFourHourTimeMode.twelveHour => _format12,
-      TwentyFourHourTimeMode.twentyFourHour => _format24,
-      TwentyFourHourTimeMode.localeDefault => _formatLocaleDefault,
+      .twelveHour => _format12,
+      .twentyFourHour => _format24,
+      .localeDefault => _formatLocaleDefault,
     };
     final text = format.format(node.datetime.toLocal());
     final contentTheme = ContentTheme.of(context);
diff --git a/lib/widgets/home.dart b/lib/widgets/home.dart
index 79ce45f4e..52c4c1a15 100644
--- a/lib/widgets/home.dart
+++ b/lib/widgets/home.dart
@@ -4,7 +4,6 @@ import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 
 import '../api/core.dart';
-import '../api/model/model.dart';
 import '../generated/l10n/zulip_localizations.dart';
 import '../model/narrow.dart';
 import 'about_zulip.dart';
@@ -871,7 +870,7 @@ class _ServerCompatBanner extends StatelessWidget {
     final showCompatBanner =
       store.zulipFeatureLevel < kMinSupportedZulipFeatureLevel
       && !globalStore.getServerCompatBannerDismissed(store.accountId);
-    final isAtLeastAdmin = store.selfUser.role.isAtLeast(UserRole.administrator);
+    final isAtLeastAdmin = store.selfUser.role.isAtLeast(.administrator);
     final label = isAtLeastAdmin
       ? zulipLocalizations.serverCompatBannerAdminMessage(
           store.realmUrl.toString(), store.zulipVersion)
diff --git a/lib/widgets/message_list.dart b/lib/widgets/message_list.dart
index 602e7c992..dfd3dff20 100644
--- a/lib/widgets/message_list.dart
+++ b/lib/widgets/message_list.dart
@@ -2257,15 +2257,15 @@ enum MessageTimestampStyle {
   static final _timeFormatLocaleDefaultWithSeconds = DateFormat('jms');
 
   static DateFormat _resolveTimeFormat(TwentyFourHourTimeMode mode) => switch (mode) {
-    TwentyFourHourTimeMode.twelveHour => _timeFormat12,
-    TwentyFourHourTimeMode.twentyFourHour => _timeFormat24,
-    TwentyFourHourTimeMode.localeDefault => _timeFormatLocaleDefault,
+    .twelveHour => _timeFormat12,
+    .twentyFourHour => _timeFormat24,
+    .localeDefault => _timeFormatLocaleDefault,
   };
 
   static DateFormat _resolveTimeFormatWithSeconds(TwentyFourHourTimeMode mode) => switch (mode) {
-    TwentyFourHourTimeMode.twelveHour => _timeFormat12WithSeconds,
-    TwentyFourHourTimeMode.twentyFourHour => _timeFormat24WithSeconds,
-    TwentyFourHourTimeMode.localeDefault => _timeFormatLocaleDefaultWithSeconds,
+    .twelveHour => _timeFormat12WithSeconds,
+    .twentyFourHour => _timeFormat24WithSeconds,
+    .localeDefault => _timeFormatLocaleDefaultWithSeconds,
   };
 
   /// Format a [Message.timestamp] for this mode.
diff --git a/lib/widgets/profile.dart b/lib/widgets/profile.dart
index f10f6211d..7bd49162d 100644
--- a/lib/widgets/profile.dart
+++ b/lib/widgets/profile.dart
@@ -191,8 +191,8 @@ class _LastActiveTimeState extends State<_LastActiveTime> with PerAccountStoreAw
     final status = model!.presenceStatusForUser(widget.userId,
       utcNow: nowDate);
     switch (status) {
-      case PresenceStatus.active: return zulipLocalizations.userActiveNow;
-      case PresenceStatus.idle:   return zulipLocalizations.userIdle;
+      case .active: return zulipLocalizations.userActiveNow;
+      case .idle:   return zulipLocalizations.userIdle;
       case null:                  break; // handle below
     }
 
@@ -297,7 +297,7 @@ class _InvisibleModeToggle extends StatelessWidget {
     return RemoteSettingBuilder<bool>(
       findValueInStore: (store) => !store.userSettings.presenceEnabled,
       sendValueToServer: (value) => updateSettings(store.connection,
-        newSettings: {UserSettingName.presenceEnabled: !value}),
+        newSettings: {.presenceEnabled: !value}),
       // TODO(#741) interpret API errors for user
       onError: (e, requestedValue) => reportErrorToUserBriefly(
         requestedValue
@@ -334,12 +334,12 @@ class _ProfileErrorPage extends StatelessWidget {
 
 String roleToLabel(UserRole role, ZulipLocalizations zulipLocalizations) {
   return switch (role) {
-    UserRole.owner => zulipLocalizations.userRoleOwner,
-    UserRole.administrator => zulipLocalizations.userRoleAdministrator,
-    UserRole.moderator => zulipLocalizations.userRoleModerator,
-    UserRole.member => zulipLocalizations.userRoleMember,
-    UserRole.guest => zulipLocalizations.userRoleGuest,
-    UserRole.unknown => zulipLocalizations.userRoleUnknown,
+    .owner => zulipLocalizations.userRoleOwner,
+    .administrator => zulipLocalizations.userRoleAdministrator,
+    .moderator => zulipLocalizations.userRoleModerator,
+    .member => zulipLocalizations.userRoleMember,
+    .guest => zulipLocalizations.userRoleGuest,
+    .unknown => zulipLocalizations.userRoleUnknown,
   };
 }
 
@@ -362,16 +362,16 @@ class _ProfileDataTable extends StatelessWidget {
     final store = PerAccountStoreWidget.of(context);
 
     switch (realmField.type) {
-      case CustomProfileFieldType.link:
+      case .link:
         return _LinkWidget(url: value, text: value);
 
-      case CustomProfileFieldType.choice:
+      case .choice:
         final choiceFieldData = _tryDecode(CustomProfileFieldChoiceDataItem.parseFieldDataChoices, realmField.fieldData);
         if (choiceFieldData == null) return null;
         final choiceItem = choiceFieldData[value];
         return (choiceItem == null) ? null : _TextWidget(text: choiceItem.text);
 
-      case CustomProfileFieldType.externalAccount:
+      case .externalAccount:
         final externalAccountFieldData = _tryDecode(CustomProfileFieldExternalAccountData.fromJson, realmField.fieldData);
         if (externalAccountFieldData == null) return null;
         final urlPattern = externalAccountFieldData.urlPattern ??
@@ -380,7 +380,7 @@ class _ProfileDataTable extends StatelessWidget {
         final url = urlPattern.replaceFirst('%(username)s', value);
         return _LinkWidget(url: url, text: value);
 
-      case CustomProfileFieldType.user:
+      case .user:
         // TODO(server): This is completely undocumented.  The key to
         //   reverse-engineering it was:
         //   https://github.com/zulip/zulip/blob/18230fcd9/static/js/settings_account.js#L247
@@ -391,21 +391,21 @@ class _ProfileDataTable extends StatelessWidget {
         return Column(
           children: userIds.map((userId) => _UserWidget(userId: userId)).toList());
 
-      case CustomProfileFieldType.date:
+      case .date:
         // TODO(server): The value's format is undocumented, but empirically
         //   it's a date in ISO format, like 2000-01-01.
         // That's readable as is, but:
         // TODO(i18n) format this date using user's locale.
         return _TextWidget(text: value);
 
-      case CustomProfileFieldType.shortText:
-      case CustomProfileFieldType.longText:
-      case CustomProfileFieldType.pronouns:
+      case .shortText:
+      case .longText:
+      case .pronouns:
         // The web client appears to treat `longText` identically to `shortText`;
         // `pronouns` is explicitly meant to display the same as `shortText`.
         return _TextWidget(text: value);
 
-      case CustomProfileFieldType.unknown:
+      case .unknown:
         return null;
     }
   }
diff --git a/lib/widgets/subscription_list.dart b/lib/widgets/subscription_list.dart
index 5143ab6c6..1ecc88195 100644
--- a/lib/widgets/subscription_list.dart
+++ b/lib/widgets/subscription_list.dart
@@ -114,7 +114,7 @@ class _SubscriptionListPageBodyState extends State<SubscriptionListPageBody> wit
       // > Guests can never subscribe themselves to a channel.
       // (Web also hides the corresponding link for guests;
       // see web/templates/left_sidebar.hbs.)
-      && store.selfUser.role.isAtLeast(UserRole.member);
+      && store.selfUser.role.isAtLeast(.member);
 
     final List<Subscription> pinned = [];
     final List<Subscription> unpinned = [];
diff --git a/lib/widgets/user.dart b/lib/widgets/user.dart
index 013dfcea0..83d9d7279 100644
--- a/lib/widgets/user.dart
+++ b/lib/widgets/user.dart
@@ -263,9 +263,9 @@ class _PresenceCircleState extends State<PresenceCircle> with PerAccountStoreAwa
         } else {
           return SizedBox.square(dimension: widget.size);
         }
-      case PresenceStatus.active:
+      case .active:
         color = designVariables.statusOnline;
-      case PresenceStatus.idle:
+      case .idle:
         gradient = LinearGradient(
           begin: AlignmentDirectional.centerStart,
           end: AlignmentDirectional.centerEnd,
diff --git a/test/api/model/events_checks.dart b/test/api/model/events_checks.dart
index 030172169..64cbb614e 100644
--- a/test/api/model/events_checks.dart
+++ b/test/api/model/events_checks.dart
@@ -15,6 +15,11 @@ extension AlertWordsEventChecks on Subject<AlertWordsEvent> {
   Subject<List<String>> get alertWords => has((e) => e.alertWords, 'alertWords');
 }
 
+extension UserSettingsUpdateEventChecks on Subject<UserSettingsUpdateEvent> {
+  Subject<UserSettingName> get property => has((e) => e.property, 'property');
+  Subject<Object?> get value => has((e) => e.value, 'value');
+}
+
 extension DeviceUpdateEventChecks on Subject<DeviceUpdateEvent> {
   Subject<JsonNullable<int>?> get pushKeyId => has((e) => e.pushKeyId, 'pushKeyId');
   Subject<JsonNullable<String>?> get pushTokenId => has((e) => e.pushTokenId, 'pushTokenId');
@@ -36,6 +41,11 @@ extension RealmUserUpdateEventChecks on Subject<RealmUserUpdateEvent> {
   Subject<JsonNullable<String>?> get deliveryEmail => has((e) => e.deliveryEmail, 'deliveryEmail');
 }
 
+extension ChannelUpdateEventChecks on Subject<ChannelUpdateEvent> {
+  Subject<ChannelProperty> get property => has((e) => e.property, 'property');
+  Subject<Object?> get value => has((e) => e.value, 'value');
+}
+
 extension SubscriptionRemoveEventChecks on Subject<SubscriptionRemoveEvent> {
   Subject<List<int>> get channelIds => has((e) => e.channelIds, 'channelIds');
 }
@@ -85,6 +95,7 @@ extension UpdateMessageFlagsMessageDetailCheck on Subject<UpdateMessageFlagsMess
 }
 
 extension TypingEventChecks on Subject<TypingEvent> {
+  Subject<TypingOp> get op => has((e) => e.op, 'op');
   Subject<MessageType> get messageType => has((e) => e.messageType, 'messageType');
   Subject<int> get senderId => has((e) => e.senderId, 'senderId');
   Subject<List<int>?> get recipientIds => has((e) => e.recipientIds, 'recipientIds');
@@ -92,6 +103,10 @@ extension TypingEventChecks on Subject<TypingEvent> {
   Subject<TopicName?> get topic => has((e) => e.topic, 'topic');
 }
 
+extension ReactionEventChecks on Subject<ReactionEvent> {
+  Subject<ReactionOp> get op => has((e) => e.op, 'op');
+}
+
 extension HeartbeatEventChecks on Subject<HeartbeatEvent> {
   // No properties not covered by Event.
 }
diff --git a/test/api/model/events_test.dart b/test/api/model/events_test.dart
index 234915c39..518ea4592 100644
--- a/test/api/model/events_test.dart
+++ b/test/api/model/events_test.dart
@@ -30,6 +30,26 @@ void main() {
     ).isEmpty();
   });
 
+  test('user_settings/update: unknown property', () {
+    final json = Map<String, dynamic>.unmodifiable({
+      'id': 1,
+      'type': 'user_settings',
+      'op': 'update',
+      'property': 'twenty_four_hour_time',
+      'value': true,
+    });
+
+    check(UserSettingsUpdateEvent.fromJson(json))
+      ..property.equals(.twentyFourHourTime)
+      ..value.equals(TwentyFourHourTimeMode.twentyFourHour);
+
+    for (final unknown in ['unknown_user_setting_name', '']) {
+      check(UserSettingsUpdateEvent.fromJson({...json, 'property': unknown}))
+        ..property.equals(.unknown)
+        ..value.equals(null);
+    }
+  });
+
   group('device/update', () {
     final baseJson = {'id': 1, 'type': 'device', 'op': 'update', 'device_id': 3 };
 
@@ -86,6 +106,28 @@ void main() {
     });
   });
 
+  test('stream/update: unknown property', () {
+    final json = Map<String, dynamic>.unmodifiable({
+      'id': 1,
+      'type': 'stream',
+      'op': 'update',
+      'stream_id': 1,
+      'name': 'channel name',
+      'property': 'is_recently_active',
+      'value': true,
+    });
+
+    check(ChannelUpdateEvent.fromJson(json))
+      ..property.equals(.isRecentlyActive)
+      ..value.equals(true);
+
+    for (final unknown in ['unknown_channel_property', '']) {
+      check(ChannelUpdateEvent.fromJson({...json, 'property': unknown}))
+        ..property.equals(.unknown)
+        ..value.equals(null);
+    }
+  });
+
   test('subscription/remove: deserialize stream_ids correctly', () {
     check(Event.fromJson({
       'id': 1,
@@ -245,6 +287,7 @@ void main() {
       'message_type': 'private',
     })).returnsNormally();
 
+    // TODO(server-future): remove
     final baseJsonStream = {
       'id': 1,
       'type': 'delete_message',
@@ -252,21 +295,31 @@ void main() {
       'message_type': 'stream',
     };
 
-    check(() => DeleteMessageEvent.fromJson({
-      ...baseJsonStream
-    })).throws<void>();
+    // Future server.
+    final baseJsonChannel = {
+      'id': 1,
+      'type': 'delete_message',
+      'message_ids': [1, 2, 3],
+      'message_type': 'channel',
+    };
 
-    check(() => DeleteMessageEvent.fromJson({
-      ...baseJsonStream, 'stream_id': 1, 'topic': 'some topic',
-    })).returnsNormally();
+    for (final baseJson in [baseJsonStream, baseJsonChannel]) {
+      check(() => DeleteMessageEvent.fromJson({
+        ...baseJson
+      })).throws<void>();
 
-    check(() => DeleteMessageEvent.fromJson({
-      ...baseJsonStream, 'stream_id': 1,
-    })).throws<void>();
+      check(() => DeleteMessageEvent.fromJson({
+        ...baseJson, 'stream_id': 1, 'topic': 'some topic',
+      })).returnsNormally();
 
-    check(() => DeleteMessageEvent.fromJson({
-      ...baseJsonStream, 'topic': 'some topic',
-    })).throws<void>();
+      check(() => DeleteMessageEvent.fromJson({
+        ...baseJson, 'stream_id': 1,
+      })).throws<void>();
+
+      check(() => DeleteMessageEvent.fromJson({
+        ...baseJson, 'topic': 'some topic',
+      })).throws<void>();
+    }
   });
 
   test('delete_message: private -> direct', () {
@@ -275,7 +328,18 @@ void main() {
       'type': 'delete_message',
       'message_ids': [1, 2, 3],
       'message_type': 'private',
-    })).messageType.equals(MessageType.direct);
+    })).messageType.equals(.direct);
+  });
+
+  test('delete_message: stream -> channel', () {
+    check(DeleteMessageEvent.fromJson({
+      'id': 1,
+      'type': 'delete_message',
+      'message_ids': [1, 2, 3],
+      'message_type': 'stream',
+      'stream_id': 1,
+      'topic': 'some topic',
+    })).messageType.equals(.channel);
   });
 
   group('update_message_flags/remove', () {
@@ -310,7 +374,17 @@ void main() {
             ...messageDetail,
             'type': 'private',
           }}})).messageDetails.isNotNull()
-               .values.single.type.equals(MessageType.direct);
+               .values.single.type.equals(.direct);
+    });
+
+    test('stream -> channel', () {
+      check(UpdateMessageFlagsRemoveEvent.fromJson({
+        ...baseJson,
+        'flag': 'read',
+        'message_details': {
+          '123': {'type': 'stream', 'mentioned': false, 'stream_id': 1, 'topic': 'some topic'}
+        }})).messageDetails.isNotNull()
+            .values.single.type.equals(.channel);
     });
   });
 
@@ -328,6 +402,16 @@ void main() {
       'recipients': [1, 2, 3].map((e) => {'user_id': e, 'email': '$e@example.com'}).toList(),
     };
 
+    test('handle unknown op', () {
+      check(TypingEvent.fromJson(directMessageJson))
+        .op.equals(.start);
+
+      for (final unknown in ['unknown_op', '']) {
+        check(TypingEvent.fromJson({...directMessageJson, 'op': unknown}))
+          .op.equals(.unknown);
+      }
+    });
+
     test('direct message typing events', () {
       check(TypingEvent.fromJson(directMessageJson))
         ..recipientIds.isNotNull().deepEquals([1, 2, 3])
@@ -343,19 +427,35 @@ void main() {
       check(TypingEvent.fromJson({
         ...directMessageJson,
         'message_type': 'private',
-      })).messageType.equals(MessageType.direct);
+      })).messageType.equals(.direct);
     });
 
-    test('stream type missing streamId/topic', () {
-      check(() => TypingEvent.fromJson({
-        ...baseJson, 'message_type': 'stream', 'stream_id': 123, 'topic': 'foo'}))
-        .returnsNormally();
-      check(() => TypingEvent.fromJson({
-        ...baseJson, 'message_type': 'stream'})).throws<void>();
-      check(() => TypingEvent.fromJson({
-        ...baseJson, 'message_type': 'stream', 'topic': 'foo'})).throws<void>();
-      check(() => TypingEvent.fromJson({
-        ...baseJson, 'message_type': 'stream', 'stream_id': 123})).throws<void>();
+    test('stream/channel type missing streamId/topic', () {
+      // TODO(server-future): remove
+      final baseJsonStream = {...baseJson, 'message_type': 'stream'};
+      // Future server.
+      final baseJsonChannel = {...baseJson, 'message_type': 'channel'};
+
+      for (final baseJson in [baseJsonStream, baseJsonChannel]) {
+        check(() => TypingEvent.fromJson({
+          ...baseJson, 'stream_id': 123, 'topic': 'foo'}))
+          .returnsNormally();
+        check(() => TypingEvent.fromJson({
+          ...baseJson})).throws<void>();
+        check(() => TypingEvent.fromJson({
+          ...baseJson, 'topic': 'foo'})).throws<void>();
+        check(() => TypingEvent.fromJson({
+          ...baseJson, 'stream_id': 123})).throws<void>();
+      }
+    });
+
+    test('stream -> channel', () {
+      check(TypingEvent.fromJson({
+        ...baseJson,
+        'stream_id': 123,
+        'topic': 'foo',
+        'message_type': 'stream',
+      })).messageType.equals(.channel);
     });
 
     test('direct type sort recipient ids', () {
@@ -365,4 +465,25 @@ void main() {
       })).recipientIds.isNotNull().deepEquals([1, 2, 4, 8, 10]);
     });
   });
+
+  group('reaction event', () {
+    final json = Map<String, dynamic>.unmodifiable({
+      'id': 1,
+      'type': 'reaction',
+      'op': 'add',
+      'emoji_name': '+1',
+      'emoji_code': '1f44d',
+      'reaction_type': 'unicode_emoji',
+      'user_id': 100,
+      'message_id': 1000,
+    });
+
+    test('handle unknown op', () {
+      check(ReactionEvent.fromJson(json)).op.equals(.add);
+
+      for (final unknown in ['unknown_op', '']) {
+        check(ReactionEvent.fromJson({...json, 'op': unknown})).op.equals(.unknown);
+      }
+    });
+  });
 }
diff --git a/test/api/model/initial_snapshot_test.dart b/test/api/model/initial_snapshot_test.dart
index 2dff367d2..918099032 100644
--- a/test/api/model/initial_snapshot_test.dart
+++ b/test/api/model/initial_snapshot_test.dart
@@ -69,7 +69,7 @@ void main() {
     for (final unknownValue in unknownValues) {
       final json = eg.userSettings().toJson()..['emojiset'] = unknownValue;
       final settings = UserSettings.fromJson(json);
-      check(settings.emojiset).equals(Emojiset.unknown);
+      check(settings.emojiset).equals(.unknown);
     }
   });
 }
diff --git a/test/api/model/model_checks.dart b/test/api/model/model_checks.dart
index dddd4d8a9..0aebdb256 100644
--- a/test/api/model/model_checks.dart
+++ b/test/api/model/model_checks.dart
@@ -109,7 +109,7 @@ extension MessageChecks on Subject<Message> {
   Subject<String> get senderFullName => has((e) => e.senderFullName, 'senderFullName');
   Subject<String> get senderRealmStr => has((e) => e.senderRealmStr, 'senderRealmStr');
   Subject<Poll?> get poll => has((e) => e.poll, 'poll');
-  Subject<String> get type => has((e) => e.type, 'type');
+  Subject<MessageType> get type => has((e) => e.type, 'type');
   Subject<List<MessageFlag>> get flags => has((e) => e.flags, 'flags');
   Subject<String?> get matchContent => has((e) => e.matchContent, 'matchContent');
   Subject<String?> get matchTopic => has((e) => e.matchTopic, 'matchTopic');
diff --git a/test/api/model/model_test.dart b/test/api/model/model_test.dart
index f04bbd6d4..2eed4d251 100644
--- a/test/api/model/model_test.dart
+++ b/test/api/model/model_test.dart
@@ -91,6 +91,16 @@ void main() {
       expected: (OptionNone(), OptionNone()));
   });
 
+  test('UserSettingName.fromRawString handles unknown values', () {
+    check(UserSettingName.fromRawString('twenty_four_hour_time'))
+      .equals(.twentyFourHourTime);
+
+    for (final unknown in ['unknown_user_setting_name', '']) {
+      check(UserSettingName.fromRawString(unknown))
+        .equals(.unknown);
+    }
+  });
+
   group('User', () {
     final Map<String, dynamic> baseJson = Map.unmodifiable({
       'user_id': 123,
@@ -131,6 +141,14 @@ void main() {
     });
   });
 
+  test('ChannelProperty.fromRawString handles unknown values', () {
+    check(ChannelProperty.fromRawString('is_recently_active')).equals(.isRecentlyActive);
+
+    for (final unknown in ['unknown_channel_property', '']) {
+      check(ChannelProperty.fromRawString(unknown)).equals(.unknown);
+    }
+  });
+
   group('Subscription', () {
     test('converts color to int', () {
       Subscription subWithColor(String color) {
@@ -149,6 +167,33 @@ void main() {
     Map<String, dynamic> baseStreamJson() =>
       deepToJson(eg.streamMessage()) as Map<String, dynamic>;
 
+    Map<String, dynamic> baseDmJson() =>
+      deepToJson(eg.dmMessage(from: eg.selfUser, to: [])) as Map<String, dynamic>;
+
+    test('type: stream -> channel', () {
+      check(baseStreamJson()['type']).equals('channel');
+      check(Message.fromJson(baseStreamJson()))
+        .isA<StreamMessage>()
+        .type.equals(.channel);
+
+      check(Message.fromJson(baseStreamJson()
+        ..['type'] = 'stream'
+      )).isA<StreamMessage>()
+        .type.equals(.channel);
+    });
+
+    test('type: private -> direct', () {
+      check(baseDmJson()['type']).equals('direct');
+      check(Message.fromJson(baseDmJson()))
+        .isA<DmMessage>()
+        .type.equals(.direct);
+
+      check(Message.fromJson(baseDmJson()
+        ..['type'] = 'private'
+      )).isA<DmMessage>()
+        .type.equals(.direct);
+    });
+
     test('subject -> topic', () {
       check(baseStreamJson()).not((it) => it.containsKey('topic'));
       check(Message.fromJson(baseStreamJson()
diff --git a/test/api/route/messages_test.dart b/test/api/route/messages_test.dart
index 1b4f86c62..0395645d0 100644
--- a/test/api/route/messages_test.dart
+++ b/test/api/route/messages_test.dart
@@ -286,7 +286,7 @@ void main() {
           localId: '456',
           readBySender: true,
           expectedBodyFields: {
-            'type': 'stream',
+            'type': 'channel',
             'to': streamId.toString(),
             'topic': topic,
             'content': content,
@@ -299,6 +299,21 @@ void main() {
 
     test('to stream', () {
       return FakeApiConnection.with_((connection) async {
+        await checkSendMessage(connection,
+          destination: StreamDestination(streamId, eg.t(topic)), content: content,
+          readBySender: true,
+          expectedBodyFields: {
+            'type': 'channel',
+            'to': streamId.toString(),
+            'topic': topic,
+            'content': content,
+            'read_by_sender': 'true',
+          });
+      });
+    });
+
+    test('to stream, with legacy type "stream"', () {
+      return FakeApiConnection.with_(zulipFeatureLevel: 247, (connection) async {
         await checkSendMessage(connection,
           destination: StreamDestination(streamId, eg.t(topic)), content: content,
           readBySender: true,
@@ -347,7 +362,7 @@ void main() {
           destination: StreamDestination(streamId, eg.t(topic)), content: content,
           readBySender: null,
           expectedBodyFields: {
-            'type': 'stream',
+            'type': 'channel',
             'to': streamId.toString(),
             'topic': topic,
             'content': content,
diff --git a/test/api/route/settings_test.dart b/test/api/route/settings_test.dart
index a89faaa99..5f2f70e45 100644
--- a/test/api/route/settings_test.dart
+++ b/test/api/route/settings_test.dart
@@ -16,24 +16,26 @@ void main() {
       final expectedBodyFields = <String, String>{};
       for (final name in UserSettingName.values) {
         switch (name) {
-          case UserSettingName.twentyFourHourTime:
+          case .twentyFourHourTime:
             newSettings[name] = TwentyFourHourTimeMode.twelveHour;
             expectedBodyFields['twenty_four_hour_time'] = 'false';
-          case UserSettingName.starredMessageCounts:
+          case .starredMessageCounts:
             newSettings[name] = false;
             expectedBodyFields['starred_message_counts'] = 'false';
-          case UserSettingName.displayEmojiReactionUsers:
+          case .displayEmojiReactionUsers:
             newSettings[name] = false;
             expectedBodyFields['display_emoji_reaction_users'] = 'false';
-          case UserSettingName.emojiset:
+          case .emojiset:
             newSettings[name] = Emojiset.googleBlob;
             expectedBodyFields['emojiset'] = 'google-blob';
-          case UserSettingName.webInboxShowChannelFolders:
+          case .webInboxShowChannelFolders:
             newSettings[name] = false;
             expectedBodyFields['web_inbox_show_channel_folders'] = 'false';
-          case UserSettingName.presenceEnabled:
+          case .presenceEnabled:
             newSettings[name] = true;
             expectedBodyFields['presence_enabled'] = 'true';
+          case .unknown:
+            continue;
         }
       }
 
@@ -52,7 +54,7 @@ void main() {
       // TODO(server-future) instead, check for twenty_four_hour_time: null
       //   (could be an error-prone part of the JSONification)
       check(() => updateSettings(connection,
-        newSettings: {UserSettingName.twentyFourHourTime: TwentyFourHourTimeMode.localeDefault})
+        newSettings: {.twentyFourHourTime: TwentyFourHourTimeMode.localeDefault})
       ).throws<AssertionError>();
     });
   });
diff --git a/test/api/route/typing_test.dart b/test/api/route/typing_test.dart
index 551f1a5a4..c6210f0a6 100644
--- a/test/api/route/typing_test.dart
+++ b/test/api/route/typing_test.dart
@@ -43,16 +43,16 @@ void main() {
   }
 
   test('send typing status start for topic', () {
-    return checkSetTypingStatusForTopic(TypingOp.start, 'start');
+    return checkSetTypingStatusForTopic(.start, 'start');
   });
 
   test('send typing status stop for topic', () {
-    return checkSetTypingStatusForTopic(TypingOp.stop, 'stop');
+    return checkSetTypingStatusForTopic(.stop, 'stop');
   });
 
   test('send typing status start for dm', () {
     return FakeApiConnection.with_((connection) {
-      return checkSetTypingStatus(connection, TypingOp.start,
+      return checkSetTypingStatus(connection, .start,
         destination: const DmDestination(userIds: userIds),
         expectedBodyFields: {
           'op': 'start',
@@ -64,7 +64,7 @@ void main() {
 
   test('legacy: use "stream" instead of "channel"', () {
     return FakeApiConnection.with_(zulipFeatureLevel: 247, (connection) {
-      return checkSetTypingStatus(connection, TypingOp.start,
+      return checkSetTypingStatus(connection, .start,
         destination: const StreamDestination(streamId, TopicName(topic)),
         expectedBodyFields: {
           'op': 'start',
@@ -77,7 +77,7 @@ void main() {
 
   test('legacy: use to=[streamId] instead of stream_id=streamId', () {
     return FakeApiConnection.with_(zulipFeatureLevel: 214, (connection) {
-      return checkSetTypingStatus(connection, TypingOp.start,
+      return checkSetTypingStatus(connection, .start,
         destination: const StreamDestination(streamId, TopicName(topic)),
         expectedBodyFields: {
           'op': 'start',
@@ -90,7 +90,7 @@ void main() {
 
   test('legacy: use "private" instead of "direct"', () {
     return FakeApiConnection.with_(zulipFeatureLevel: 173, (connection) {
-      return checkSetTypingStatus(connection, TypingOp.start,
+      return checkSetTypingStatus(connection, .start,
         destination: const DmDestination(userIds: userIds),
         expectedBodyFields: {
           'op': 'start',
diff --git a/test/api/route/users_test.dart b/test/api/route/users_test.dart
index 16975bbc2..deb33532c 100644
--- a/test/api/route/users_test.dart
+++ b/test/api/route/users_test.dart
@@ -41,7 +41,7 @@ void main() {
         historyLimitDays: 21,
         newUserInput: false,
         pingOnly: false,
-        status: PresenceStatus.active,
+        status: .active,
       );
       check(connection.takeRequests()).single.isA<http.Request>()
         ..method.equals('POST')
diff --git a/test/example_data.dart b/test/example_data.dart
index 820f00497..ba9a72140 100644
--- a/test/example_data.dart
+++ b/test/example_data.dart
@@ -309,7 +309,7 @@ User user({
     isBot: isBot ?? false,
     botType: null,
     botOwnerId: botOwnerId,
-    role: role ?? UserRole.member,
+    role: role ?? .member,
     timezone: 'UTC',
     avatarUrl: avatarUrl,
     avatarVersion: 0,
@@ -801,7 +801,7 @@ StreamMessage streamMessage({
     'subject': topic ?? _defaultTopic,
     'submessages': submessages ?? [],
     'timestamp': timestamp ?? 1678139636,
-    'type': 'stream',
+    'type': 'channel',
     'match_content': matchContent,
     'match_subject': matchTopic,
   }) as Map<String, dynamic>);
@@ -844,7 +844,7 @@ DmMessage dmMessage({
     'subject': '',
     'submessages': submessages ?? [],
     'timestamp': timestamp ?? 1678139636,
-    'type': 'private',
+    'type': 'direct',
   }) as Map<String, dynamic>);
 }
 
@@ -1107,7 +1107,7 @@ DeleteMessageEvent deleteMessageEvent(List<StreamMessage> messages) {
   return DeleteMessageEvent(
     id: 0,
     messageIds: messages.map((message) => message.id).toList(),
-    messageType: MessageType.stream,
+    messageType: .channel,
     streamId: messages[0].streamId,
     topic: messages[0].topic,
   );
@@ -1255,14 +1255,14 @@ UpdateMessageFlagsRemoveEvent updateMessageFlagsRemoveEvent(
         message.id,
         switch (message) {
           StreamMessage() => UpdateMessageFlagsMessageDetail(
-            type: MessageType.stream,
+            type: .channel,
             mentioned: mentioned,
             streamId: message.streamId,
             topic: message.topic,
             userIds: null,
           ),
           DmMessage() => UpdateMessageFlagsMessageDetail(
-            type: MessageType.direct,
+            type: .direct,
             mentioned: mentioned,
             streamId: null,
             topic: null,
@@ -1293,13 +1293,13 @@ TypingEvent typingEvent(SendableNarrow narrow, TypingOp op, int senderId) {
   switch (narrow) {
     case TopicNarrow():
       return TypingEvent(id: 0, op: op, senderId: senderId,
-        messageType: MessageType.stream,
+        messageType: .channel,
         streamId: narrow.channelId,
         topic: narrow.topic,
         recipientIds: null);
     case DmNarrow():
       return TypingEvent(id: 0, op: op, senderId: senderId,
-        messageType: MessageType.direct,
+        messageType: .direct,
         recipientIds: narrow.allRecipientIds,
         streamId: null,
         topic: null);
@@ -1320,38 +1320,40 @@ ReactionEvent reactionEvent(Reaction reaction, ReactionOp op, int messageId) {
 
 ChannelUpdateEvent channelUpdateEvent(
   ZulipStream stream, {
-  required ChannelPropertyName property,
+  required ChannelProperty property,
   required Object? value,
 }) {
   switch (property) {
-    case ChannelPropertyName.name:
+    case .name:
       assert(value is String);
-    case ChannelPropertyName.isArchived:
+    case .isArchived:
       assert(value is bool);
-    case ChannelPropertyName.description:
+    case .description:
       assert(value is String);
-    case ChannelPropertyName.firstMessageId:
+    case .firstMessageId:
       assert(value is int?);
-    case ChannelPropertyName.inviteOnly:
+    case .inviteOnly:
       assert(value is bool);
-    case ChannelPropertyName.messageRetentionDays:
+    case .messageRetentionDays:
       assert(value is int?);
-    case ChannelPropertyName.topicsPolicy:
+    case .topicsPolicy:
       assert(value is ChannelTopicsPolicy);
-    case ChannelPropertyName.channelPostPolicy:
+    case .channelPostPolicy:
       assert(value is ChannelPostPolicy);
-    case ChannelPropertyName.folderId:
+    case .folderId:
       assert(value is int?);
-    case ChannelPropertyName.canAddSubscribersGroup:
-    case ChannelPropertyName.canDeleteAnyMessageGroup:
-    case ChannelPropertyName.canDeleteOwnMessageGroup:
-    case ChannelPropertyName.canSendMessageGroup:
-    case ChannelPropertyName.canSubscribeGroup:
+    case .canAddSubscribersGroup:
+    case .canDeleteAnyMessageGroup:
+    case .canDeleteOwnMessageGroup:
+    case .canSendMessageGroup:
+    case .canSubscribeGroup:
       assert(value is GroupSettingValue);
-    case ChannelPropertyName.isRecentlyActive:
+    case .isRecentlyActive:
       assert(value is bool);
-    case ChannelPropertyName.streamWeeklyTraffic:
+    case .streamWeeklyTraffic:
       assert(value is int?);
+    case .unknown:
+      assert(value == null);
   }
   return ChannelUpdateEvent(
     id: 1,
@@ -1393,10 +1395,10 @@ UserSettings userSettings({
   bool? presenceEnabled,
 }) {
   return UserSettings(
-    twentyFourHourTime: twentyFourHourTime ?? TwentyFourHourTimeMode.twelveHour,
+    twentyFourHourTime: twentyFourHourTime ?? .twelveHour,
     starredMessageCounts: true,
     displayEmojiReactionUsers: displayEmojiReactionUsers ?? true,
-    emojiset: emojiset ?? Emojiset.google,
+    emojiset: emojiset ?? .google,
     webInboxShowChannelFolders: webInboxShowChannelFolders ?? true,
     presenceEnabled: presenceEnabled ?? true,
   );
@@ -1502,7 +1504,7 @@ InitialSnapshot initialSnapshot({
     realmCanDeleteAnyMessageGroup: realmCanDeleteAnyMessageGroup,
     realmCanDeleteOwnMessageGroup: realmCanDeleteOwnMessageGroup,
     realmDeleteOwnMessagePolicy: realmDeleteOwnMessagePolicy,
-    realmWildcardMentionPolicy: realmWildcardMentionPolicy ?? RealmWildcardMentionPolicy.everyone,
+    realmWildcardMentionPolicy: realmWildcardMentionPolicy ?? .everyone,
     // no default; allow `null` to simulate servers without this
     realmTopicsPolicy: realmTopicsPolicy,
     realmMandatoryTopics: realmMandatoryTopics ?? true,
diff --git a/test/model/channel_test.dart b/test/model/channel_test.dart
index 9c0369524..e99a9017a 100644
--- a/test/model/channel_test.dart
+++ b/test/model/channel_test.dart
@@ -63,12 +63,12 @@ void main() {
       checkUnified(store);
 
       await store.handleEvent(eg.channelUpdateEvent(store.streams[stream1.streamId]!,
-        property: ChannelPropertyName.name, value: 'new stream',
+        property: .name, value: 'new stream',
       ));
       checkUnified(store);
 
       await store.handleEvent(eg.channelUpdateEvent(store.streams[stream1.streamId]!,
-        property: ChannelPropertyName.channelPostPolicy,
+        property: .channelPostPolicy,
         value: ChannelPostPolicy.administrators,
       ));
       checkUnified(store);
@@ -587,33 +587,33 @@ void main() {
   });
 
   group('selfCanSendMessage, legacy', () {
-    final testCases = [
-      (ChannelPostPolicy.unknown,        UserRole.guest,         true),
-      (ChannelPostPolicy.unknown,        UserRole.member,        true),
-      (ChannelPostPolicy.unknown,        UserRole.moderator,     true),
-      (ChannelPostPolicy.unknown,        UserRole.administrator, true),
-      (ChannelPostPolicy.unknown,        UserRole.owner,         true),
-      (ChannelPostPolicy.any,            UserRole.guest,         true),
-      (ChannelPostPolicy.any,            UserRole.member,        true),
-      (ChannelPostPolicy.any,            UserRole.moderator,     true),
-      (ChannelPostPolicy.any,            UserRole.administrator, true),
-      (ChannelPostPolicy.any,            UserRole.owner,         true),
-      (ChannelPostPolicy.fullMembers,    UserRole.guest,         false),
+    final testCases = <(ChannelPostPolicy, UserRole, bool)>[
+      (ChannelPostPolicy.unknown,        .guest,         true),
+      (ChannelPostPolicy.unknown,        .member,        true),
+      (ChannelPostPolicy.unknown,        .moderator,     true),
+      (ChannelPostPolicy.unknown,        .administrator, true),
+      (ChannelPostPolicy.unknown,        .owner,         true),
+      (ChannelPostPolicy.any,            .guest,         true),
+      (ChannelPostPolicy.any,            .member,        true),
+      (ChannelPostPolicy.any,            .moderator,     true),
+      (ChannelPostPolicy.any,            .administrator, true),
+      (ChannelPostPolicy.any,            .owner,         true),
+      (ChannelPostPolicy.fullMembers,    .guest,         false),
       // The fullMembers/member case gets its own tests further below.
-      // (ChannelPostPolicy.fullMembers,    UserRole.member,        /* complicated */),
-      (ChannelPostPolicy.fullMembers,    UserRole.moderator,     true),
-      (ChannelPostPolicy.fullMembers,    UserRole.administrator, true),
-      (ChannelPostPolicy.fullMembers,    UserRole.owner,         true),
-      (ChannelPostPolicy.moderators,     UserRole.guest,         false),
-      (ChannelPostPolicy.moderators,     UserRole.member,        false),
-      (ChannelPostPolicy.moderators,     UserRole.moderator,     true),
-      (ChannelPostPolicy.moderators,     UserRole.administrator, true),
-      (ChannelPostPolicy.moderators,     UserRole.owner,         true),
-      (ChannelPostPolicy.administrators, UserRole.guest,         false),
-      (ChannelPostPolicy.administrators, UserRole.member,        false),
-      (ChannelPostPolicy.administrators, UserRole.moderator,     false),
-      (ChannelPostPolicy.administrators, UserRole.administrator, true),
-      (ChannelPostPolicy.administrators, UserRole.owner,         true),
+      // (ChannelPostPolicy.fullMembers,    .member,        /* complicated */),
+      (ChannelPostPolicy.fullMembers,    .moderator,     true),
+      (ChannelPostPolicy.fullMembers,    .administrator, true),
+      (ChannelPostPolicy.fullMembers,    .owner,         true),
+      (ChannelPostPolicy.moderators,     .guest,         false),
+      (ChannelPostPolicy.moderators,     .member,        false),
+      (ChannelPostPolicy.moderators,     .moderator,     true),
+      (ChannelPostPolicy.moderators,     .administrator, true),
+      (ChannelPostPolicy.moderators,     .owner,         true),
+      (ChannelPostPolicy.administrators, .guest,         false),
+      (ChannelPostPolicy.administrators, .member,        false),
+      (ChannelPostPolicy.administrators, .moderator,     false),
+      (ChannelPostPolicy.administrators, .administrator, true),
+      (ChannelPostPolicy.administrators, .owner,         true),
     ];
 
     for (final (ChannelPostPolicy policy, UserRole role, bool canPost) in testCases) {
@@ -643,7 +643,7 @@ void main() {
           realmUsers: [selfUser]));
 
       User memberUser({required String dateJoined}) => eg.user(
-        role: UserRole.member, dateJoined: dateJoined);
+        role: .member, dateJoined: dateJoined);
 
       test('a "full" member -> can post in the channel', () {
         final store = localStore(
diff --git a/test/model/message_list_test.dart b/test/model/message_list_test.dart
index ac484bf64..45c8aaa69 100644
--- a/test/model/message_list_test.dart
+++ b/test/model/message_list_test.dart
@@ -2193,7 +2193,7 @@ void main() {
       await store.addMessage(message);
 
       await store.handleEvent(
-        eg.reactionEvent(eg.unicodeEmojiReaction, ReactionOp.add, message.id));
+        eg.reactionEvent(eg.unicodeEmojiReaction, .add, message.id));
 
       check(notifiedCount1).equals(3); // fetch, new-message event, reaction event
       check(notifiedCount2).equals(3); // fetch, new-message event, reaction event
@@ -2236,7 +2236,7 @@ void main() {
     test('ReactionEvent is applied even when message not in any msglists', () async {
       await checkApplied(
         mkEvent: (message) =>
-          eg.reactionEvent(eg.unicodeEmojiReaction, ReactionOp.add, message.id),
+          eg.reactionEvent(eg.unicodeEmojiReaction, .add, message.id),
         doCheckMessageAfterFetch:
           (messageSubject) => messageSubject.reactions.isNotNull().total.equals(1),
       );
diff --git a/test/model/message_test.dart b/test/model/message_test.dart
index 9b8517c6d..af1b37edd 100644
--- a/test/model/message_test.dart
+++ b/test/model/message_test.dart
@@ -159,7 +159,7 @@ void main() {
         ..method.equals('POST')
         ..url.path.equals('/api/v1/messages')
         ..bodyFields.deepEquals({
-          'type': 'stream',
+          'type': 'channel',
           'to': stream.streamId.toString(),
           'topic': 'world',
           'content': 'hello',
@@ -1365,8 +1365,8 @@ void main() {
               timeLimitConfig: CanDeleteMessageTimeLimitConfig.notLimited,
               inRealmCanDeleteAnyMessageGroup: false,
               isChannelArchived: false,
-              realmDeleteOwnMessagePolicy: RealmDeleteOwnMessagePolicy.everyone,
-              selfUserRole: UserRole.member,
+              realmDeleteOwnMessagePolicy: .everyone,
+              selfUserRole: .member,
           )))
             ..equals(await evaluate(
              CanDeleteMessageParams.pre407(
@@ -1385,8 +1385,8 @@ void main() {
               timeLimitConfig: CanDeleteMessageTimeLimitConfig.notLimited,
               inRealmCanDeleteAnyMessageGroup: false,
               isChannelArchived: false,
-              realmDeleteOwnMessagePolicy: RealmDeleteOwnMessagePolicy.admins,
-              selfUserRole: UserRole.administrator,
+              realmDeleteOwnMessagePolicy: .admins,
+              selfUserRole: .administrator,
           )))
             ..equals(await evaluate(
              CanDeleteMessageParams.pre407(
@@ -1405,8 +1405,8 @@ void main() {
               timeLimitConfig: CanDeleteMessageTimeLimitConfig.notLimited,
               inRealmCanDeleteAnyMessageGroup: false,
               isChannelArchived: false,
-              realmDeleteOwnMessagePolicy: RealmDeleteOwnMessagePolicy.admins,
-              selfUserRole: UserRole.moderator,
+              realmDeleteOwnMessagePolicy: .admins,
+              selfUserRole: .moderator,
           )))..equals(await evaluate(
               CanDeleteMessageParams.pre407(
                 senderConfig: CanDeleteMessageSenderConfig.self,
@@ -1429,16 +1429,16 @@ void main() {
               senderConfig: CanDeleteMessageSenderConfig.otherHuman,
               timeLimitConfig: CanDeleteMessageTimeLimitConfig.notLimited,
               isChannelArchived: false,
-              realmDeleteOwnMessagePolicy: RealmDeleteOwnMessagePolicy.everyone,
-              selfUserRole: UserRole.member,
+              realmDeleteOwnMessagePolicy: .everyone,
+              selfUserRole: .member,
           )))..equals(await evaluate(
               CanDeleteMessageParams.pre291(
                 senderConfig: CanDeleteMessageSenderConfig.otherHuman,
                 timeLimitConfig: CanDeleteMessageTimeLimitConfig.notLimited,
                 inRealmCanDeleteAnyMessageGroup: false,
                 isChannelArchived: false,
-                realmDeleteOwnMessagePolicy: RealmDeleteOwnMessagePolicy.everyone,
-                selfUserRole: UserRole.member)))
+                realmDeleteOwnMessagePolicy: .everyone,
+                selfUserRole: .member)))
             ..isFalse();
         });
 
@@ -1448,16 +1448,16 @@ void main() {
               senderConfig: CanDeleteMessageSenderConfig.otherHuman,
               timeLimitConfig: CanDeleteMessageTimeLimitConfig.notLimited,
               isChannelArchived: false,
-              realmDeleteOwnMessagePolicy: RealmDeleteOwnMessagePolicy.everyone,
-              selfUserRole: UserRole.administrator,
+              realmDeleteOwnMessagePolicy: .everyone,
+              selfUserRole: .administrator,
           )))..equals(await evaluate(
               CanDeleteMessageParams.pre291(
                 senderConfig: CanDeleteMessageSenderConfig.otherHuman,
                 timeLimitConfig: CanDeleteMessageTimeLimitConfig.notLimited,
                 inRealmCanDeleteAnyMessageGroup: true,
                 isChannelArchived: false,
-                realmDeleteOwnMessagePolicy: RealmDeleteOwnMessagePolicy.everyone,
-                selfUserRole: UserRole.administrator)))
+                realmDeleteOwnMessagePolicy: .everyone,
+                selfUserRole: .administrator)))
             ..isTrue();
         });
       });
@@ -1915,7 +1915,7 @@ void main() {
       final message = store.messages.values.single;
 
       await store.handleEvent(
-        eg.reactionEvent(eg.unicodeEmojiReaction, ReactionOp.add, originalMessage.id));
+        eg.reactionEvent(eg.unicodeEmojiReaction, .add, originalMessage.id));
       checkNotifiedOnce();
       check(store.messages).values.single
         ..identicalTo(message)
@@ -1927,7 +1927,7 @@ void main() {
       await prepare();
       await prepareMessages([someMessage]);
       await store.handleEvent(
-        eg.reactionEvent(eg.unicodeEmojiReaction, ReactionOp.add, 1000));
+        eg.reactionEvent(eg.unicodeEmojiReaction, .add, 1000));
       checkNotNotified();
       check(store.messages).values.single
         .reactions.isNull();
@@ -1959,7 +1959,7 @@ void main() {
       final message = store.messages.values.single;
 
       await store.handleEvent(
-        eg.reactionEvent(eventReaction, ReactionOp.remove, originalMessage.id));
+        eg.reactionEvent(eventReaction, .remove, originalMessage.id));
       checkNotifiedOnce();
       check(store.messages).values.single
         ..identicalTo(message)
@@ -1971,7 +1971,7 @@ void main() {
       await prepare();
       await prepareMessages([someMessage]);
       await store.handleEvent(
-        eg.reactionEvent(eg.unicodeEmojiReaction, ReactionOp.remove, 1000));
+        eg.reactionEvent(eg.unicodeEmojiReaction, .remove, 1000));
       checkNotNotified();
       check(store.messages).values.single
         .reactions.isNotNull().jsonEquals([eg.unicodeEmojiReaction]);
diff --git a/test/model/realm_test.dart b/test/model/realm_test.dart
index 404d67446..c9c395031 100644
--- a/test/model/realm_test.dart
+++ b/test/model/realm_test.dart
@@ -94,21 +94,21 @@ void main() {
     });
 
     test('guest -> no permission, despite group', () {
-      final selfUser = eg.user(role: UserRole.guest);
+      final selfUser = eg.user(role: .guest);
       final group = eg.userGroup(members: [selfUser.userId]);
       check(hasPermission(selfUser, group, 'can_subscribe_group'))
         .isFalse();
     });
 
     test('guest -> still has permission, if allowEveryoneGroup', () {
-      final selfUser = eg.user(role: UserRole.guest);
+      final selfUser = eg.user(role: .guest);
       final group = eg.userGroup(members: [selfUser.userId]);
       check(hasPermission(selfUser, group, 'can_send_message_group'))
         .isTrue();
     });
 
     test('guest not in group -> no permission, even if allowEveryoneGroup', () {
-      final selfUser = eg.user(role: UserRole.guest);
+      final selfUser = eg.user(role: .guest);
       final group = eg.userGroup(members: []);
       check(hasPermission(selfUser, group, 'can_send_message_group'))
         .isFalse();
@@ -141,16 +141,16 @@ void main() {
             break;
           case SystemGroupName.everyone:
             test('everyone', () {
-              prepare(selfUserRole: UserRole.guest);
+              prepare(selfUserRole: .guest);
               doCheck(GroupSettingType.realm, 'can_access_all_users_group', true);
             });
           case SystemGroupName.members:
             test('members, is guest', () {
-              prepare(selfUserRole: UserRole.guest);
+              prepare(selfUserRole: .guest);
               doCheck(GroupSettingType.realm, 'can_add_custom_emoji_group', false);
             });
             test('members, is member', () {
-              prepare(selfUserRole: UserRole.member);
+              prepare(selfUserRole: .member);
               doCheck(GroupSettingType.realm, 'can_add_custom_emoji_group', true);
             });
           case SystemGroupName.fullMembers:
@@ -158,34 +158,34 @@ void main() {
             break;
           case SystemGroupName.moderators:
             test('moderators, is member', () {
-              prepare(selfUserRole: UserRole.member);
+              prepare(selfUserRole: .member);
               doCheck(GroupSettingType.realm, 'can_set_delete_message_policy_group', false);
             });
             test('moderators, is moderator', () {
-              prepare(selfUserRole: UserRole.moderator);
+              prepare(selfUserRole: .moderator);
               doCheck(GroupSettingType.realm, 'can_set_delete_message_policy_group', true);
             });
           case SystemGroupName.administrators:
             test('administrators, is moderator', () {
-              prepare(selfUserRole: UserRole.moderator);
+              prepare(selfUserRole: .moderator);
               doCheck(GroupSettingType.stream, 'can_remove_subscribers_group', false);
             });
             test('administrators, is administrator', () {
-              prepare(selfUserRole: UserRole.administrator);
+              prepare(selfUserRole: .administrator);
               doCheck(GroupSettingType.stream, 'can_remove_subscribers_group', true);
             });
           case SystemGroupName.owners:
             test('owners, is administrator', () {
-              prepare(selfUserRole: UserRole.administrator);
+              prepare(selfUserRole: .administrator);
               doCheck(GroupSettingType.realm, 'can_create_web_public_channel_group', false);
             });
             test('owners, is owner', () {
-              prepare(selfUserRole: UserRole.owner);
+              prepare(selfUserRole: .owner);
               doCheck(GroupSettingType.realm, 'can_create_web_public_channel_group', true);
             });
           case SystemGroupName.nobody:
             test('nobody', () {
-              prepare(selfUserRole: UserRole.owner);
+              prepare(selfUserRole: .owner);
               doCheck(GroupSettingType.stream, 'can_delete_own_message_group', false);
             });
         }
@@ -194,7 +194,7 @@ void main() {
       test('throw on unknown name', () {
         // We should know about all the permissions we're trying to implement,
         // even the ones old servers don't know about.
-        prepare(selfUserRole: UserRole.member);
+        prepare(selfUserRole: .member);
         check(() => store.selfHasPermissionForGroupSetting(null,
           GroupSettingType.realm, 'example_future_permission_name'),
         ).throws<Error>();
@@ -206,14 +206,14 @@ void main() {
     test('update clobbers old list', () async {
       final store = eg.store(initialSnapshot: eg.initialSnapshot(
         customProfileFields: [
-          eg.customProfileField(0, CustomProfileFieldType.shortText),
-          eg.customProfileField(1, CustomProfileFieldType.shortText),
+          eg.customProfileField(0, .shortText),
+          eg.customProfileField(1, .shortText),
         ]));
       check(store.customProfileFields.map((f) => f.id)).deepEquals([0, 1]);
 
       await store.handleEvent(CustomProfileFieldsEvent(id: 0, fields: [
-        eg.customProfileField(0, CustomProfileFieldType.shortText),
-        eg.customProfileField(2, CustomProfileFieldType.shortText),
+        eg.customProfileField(0, .shortText),
+        eg.customProfileField(2, .shortText),
       ]));
       check(store.customProfileFields.map((f) => f.id)).deepEquals([0, 2]);
     });
@@ -222,22 +222,22 @@ void main() {
       // Sorts both the data from the initial snapshot…
       final store = eg.store(initialSnapshot: eg.initialSnapshot(
         customProfileFields: [
-          eg.customProfileField(0, CustomProfileFieldType.shortText,
+          eg.customProfileField(0, .shortText,
             displayInProfileSummary: false),
-          eg.customProfileField(1, CustomProfileFieldType.shortText,
+          eg.customProfileField(1, .shortText,
             displayInProfileSummary: true),
-          eg.customProfileField(2, CustomProfileFieldType.shortText,
+          eg.customProfileField(2, .shortText,
             displayInProfileSummary: false),
         ]));
       check(store.customProfileFields.map((f) => f.id)).deepEquals([1, 0, 2]);
 
       // … and from an event.
       await store.handleEvent(CustomProfileFieldsEvent(id: 0, fields: [
-        eg.customProfileField(0, CustomProfileFieldType.shortText,
+        eg.customProfileField(0, .shortText,
           displayInProfileSummary: false),
-        eg.customProfileField(1, CustomProfileFieldType.shortText,
+        eg.customProfileField(1, .shortText,
           displayInProfileSummary: false),
-        eg.customProfileField(2, CustomProfileFieldType.shortText,
+        eg.customProfileField(2, .shortText,
           displayInProfileSummary: true),
       ]));
       check(store.customProfileFields.map((f) => f.id)).deepEquals([2, 0, 1]);
diff --git a/test/model/recent_senders_test.dart b/test/model/recent_senders_test.dart
index e8435fb17..62e2f4a62 100644
--- a/test/model/recent_senders_test.dart
+++ b/test/model/recent_senders_test.dart
@@ -179,7 +179,7 @@ void main() {
     model.handleDeleteMessageEvent(DeleteMessageEvent(
       id: 0,
       messageIds: [messages[1].id],
-      messageType: MessageType.stream,
+      messageType: .channel,
       streamId: stream.streamId,
       topic: eg.t('oThEr'),
     ), {messages[1].id: messages[1]});
diff --git a/test/model/store_test.dart b/test/model/store_test.dart
index d4852153c..e5476ec05 100644
--- a/test/model/store_test.dart
+++ b/test/model/store_test.dart
@@ -12,7 +12,6 @@ import 'package:zulip/api/core.dart';
 import 'package:zulip/api/exception.dart';
 import 'package:zulip/api/model/events.dart';
 import 'package:zulip/api/model/initial_snapshot.dart';
-import 'package:zulip/api/model/model.dart';
 import 'package:zulip/api/route/events.dart';
 import 'package:zulip/api/route/realm.dart';
 import 'package:zulip/log.dart';
@@ -815,15 +814,14 @@ void main() {
 
       // Pick some arbitrary event and check it gets processed on the store.
       check(store.userSettings.twentyFourHourTime)
-        .equals(TwentyFourHourTimeMode.twelveHour);
+        .equals(.twelveHour);
       connection.prepare(json: GetEventsResult(events: [
-        UserSettingsUpdateEvent(id: 2,
-          property: UserSettingName.twentyFourHourTime, value: true),
+        UserSettingsUpdateEvent(id: 2, property: .twentyFourHourTime, value: true),
       ], queueId: null).toJson());
       updateMachine.debugAdvanceLoop();
       async.elapse(Duration.zero);
       check(store.userSettings.twentyFourHourTime)
-        .equals(TwentyFourHourTimeMode.twentyFourHour);
+        .equals(.twentyFourHour);
     }));
 
     void checkReload(FutureOr<void> Function() prepareError, {
@@ -854,15 +852,14 @@ void main() {
         updateMachine.debugPauseLoop();
         updateMachine.poll();
         check(store.userSettings.twentyFourHourTime)
-          .equals(TwentyFourHourTimeMode.twelveHour);
+          .equals(.twelveHour);
         connection.prepare(json: GetEventsResult(events: [
-          UserSettingsUpdateEvent(id: 2,
-            property: UserSettingName.twentyFourHourTime, value: true),
+          UserSettingsUpdateEvent(id: 2, property: .twentyFourHourTime, value: true),
         ], queueId: null).toJson());
         updateMachine.debugAdvanceLoop();
         async.elapse(Duration.zero);
         check(store.userSettings.twentyFourHourTime)
-          .equals(TwentyFourHourTimeMode.twentyFourHour);
+          .equals(.twentyFourHour);
       });
     }
 
diff --git a/test/model/test_store.dart b/test/model/test_store.dart
index ef75659c0..47dc93b44 100644
--- a/test/model/test_store.dart
+++ b/test/model/test_store.dart
@@ -366,7 +366,7 @@ extension PerAccountStoreTestExtension on PerAccountStore {
 
   Future<void> updateChannel(
     int channelId,
-    ChannelPropertyName property,
+    ChannelProperty property,
     Object? value,
   ) async {
     await handleEvent(ChannelUpdateEvent(
diff --git a/test/model/typing_status_test.dart b/test/model/typing_status_test.dart
index eb0cc83d0..d31691a4c 100644
--- a/test/model/typing_status_test.dart
+++ b/test/model/typing_status_test.dart
@@ -88,7 +88,7 @@ void main() {
 
     typistsByNarrow.forEach((narrow, typists) {
       for (final typist in typists) {
-        handleTypingEvent(narrow, TypingOp.start, typist);
+        handleTypingEvent(narrow, .start, typist);
         checkNotifiedOnce();
       }
     });
@@ -114,15 +114,15 @@ void main() {
     test('add typists in separate narrows', () {
       prepareModel();
 
-      handleTypingEvent(dmNarrow, TypingOp.start, eg.otherUser);
+      handleTypingEvent(dmNarrow, .start, eg.otherUser);
       checkTypists({dmNarrow: [eg.otherUser]});
       checkNotifiedOnce();
 
-      handleTypingEvent(groupNarrow, TypingOp.start, eg.thirdUser);
+      handleTypingEvent(groupNarrow, .start, eg.thirdUser);
       checkTypists({dmNarrow: [eg.otherUser], groupNarrow: [eg.thirdUser]});
       checkNotifiedOnce();
 
-      handleTypingEvent(topicNarrow, TypingOp.start, eg.fourthUser);
+      handleTypingEvent(topicNarrow, .start, eg.fourthUser);
       checkTypists({
         dmNarrow: [eg.otherUser],
         groupNarrow: [eg.thirdUser],
@@ -133,7 +133,7 @@ void main() {
     test('add a typist in the same narrow', () {
       prepareModel(typistsByNarrow: {groupNarrow: [eg.otherUser]});
 
-      handleTypingEvent(groupNarrow, TypingOp.start, eg.thirdUser);
+      handleTypingEvent(groupNarrow, .start, eg.thirdUser);
       checkTypists({groupNarrow: [eg.otherUser, eg.thirdUser]});
       checkNotifiedOnce();
     });
@@ -142,7 +142,7 @@ void main() {
       prepareModel();
 
       model.handleTypingEvent(
-        eg.typingEvent(groupNarrow, TypingOp.start, eg.selfUser.userId));
+        eg.typingEvent(groupNarrow, .start, eg.selfUser.userId));
       checkTypists({});
       checkNotNotified();
     });
@@ -152,7 +152,7 @@ void main() {
     test('remove a typist from an unknown narrow', () {
       prepareModel(typistsByNarrow:  {groupNarrow: [eg.otherUser]});
 
-      handleTypingEvent(dmNarrow, TypingOp.stop, eg.otherUser);
+      handleTypingEvent(dmNarrow, .stop, eg.otherUser);
       checkTypists({groupNarrow: [eg.otherUser]});
       checkNotNotified();
     });
@@ -160,7 +160,7 @@ void main() {
     test('remove an unknown typist from a known narrow', () {
       prepareModel(typistsByNarrow:  {groupNarrow: [eg.otherUser]});
 
-      handleTypingEvent(groupNarrow, TypingOp.stop, eg.thirdUser);
+      handleTypingEvent(groupNarrow, .stop, eg.thirdUser);
       checkTypists({groupNarrow: [eg.otherUser]});
       checkNotNotified();
     });
@@ -170,7 +170,7 @@ void main() {
         groupNarrow: [eg.otherUser, eg.thirdUser],
       });
 
-      handleTypingEvent(groupNarrow, TypingOp.stop, eg.otherUser);
+      handleTypingEvent(groupNarrow, .stop, eg.otherUser);
       checkTypists({groupNarrow: [eg.thirdUser]});
       checkNotifiedOnce();
     });
@@ -178,7 +178,7 @@ void main() {
     test('remove all typists in a narrow', () {
       prepareModel(typistsByNarrow: {dmNarrow: [eg.otherUser]});
 
-      handleTypingEvent(dmNarrow, TypingOp.stop, eg.otherUser);
+      handleTypingEvent(dmNarrow, .stop, eg.otherUser);
       checkTypists({});
       checkNotifiedOnce();
     });
@@ -190,15 +190,15 @@ void main() {
         topicNarrow: [eg.fourthUser],
       });
 
-      handleTypingEvent(groupNarrow, TypingOp.stop, eg.thirdUser);
+      handleTypingEvent(groupNarrow, .stop, eg.thirdUser);
       checkTypists({dmNarrow: [eg.otherUser], topicNarrow: [eg.fourthUser]});
       checkNotifiedOnce();
 
-      handleTypingEvent(dmNarrow, TypingOp.stop, eg.otherUser);
+      handleTypingEvent(dmNarrow, .stop, eg.otherUser);
       checkTypists({topicNarrow: [eg.fourthUser]});
       checkNotifiedOnce();
 
-      handleTypingEvent(topicNarrow, TypingOp.stop, eg.fourthUser);
+      handleTypingEvent(topicNarrow, .stop, eg.fourthUser);
       checkTypists({});
       checkNotifiedOnce();
     });
@@ -222,7 +222,7 @@ void main() {
       prepareModel(typistsByNarrow: {dmNarrow: [eg.otherUser]});
       check(async.pendingTimers).length.equals(1);
 
-      handleTypingEvent(dmNarrow, TypingOp.stop, eg.otherUser);
+      handleTypingEvent(dmNarrow, .stop, eg.otherUser);
       checkTypists({});
       check(async.pendingTimers).isEmpty();
       checkNotifiedOnce();
@@ -235,7 +235,7 @@ void main() {
       async.elapse(const Duration(seconds: 10));
       checkTypists({dmNarrow: [eg.otherUser]});
       // The timer should restart from the event.
-      handleTypingEvent(dmNarrow, TypingOp.start, eg.otherUser);
+      handleTypingEvent(dmNarrow, .start, eg.otherUser);
       check(async.pendingTimers).length.equals(1);
       checkNotNotified();
 
@@ -282,7 +282,7 @@ void main() {
       await prepare();
       connection.prepare(json: {});
       model.keystroke(narrow);
-      checkTypingRequest(TypingOp.start, narrow);
+      checkTypingRequest(.start, narrow);
 
       // Finish the pending API request first,
       // so that the idle timer is the only timer left.
@@ -316,7 +316,7 @@ void main() {
       async.elapse(const Duration(milliseconds: 1));
       // t = typingStoppedWaitPeriod + 100ms:
       //   The new timer expires and the "typing stopped" notice is sent.
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     }));
 
     test('start typing repeatedly does not resend "typing started" notices', () => awaitFakeAsync((async) async {
@@ -342,12 +342,12 @@ void main() {
       // t > typingStartedWaitPeriod: Resume sending "typing started" notices.
       connection.prepare(json: {});
       model.keystroke(narrow);
-      checkTypingRequest(TypingOp.start, narrow);
+      checkTypingRequest(.start, narrow);
 
       // Ensures that a "typing stopped" notice is sent when the test ends.
       connection.prepare(json: {});
       async.flushTimers();
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     }));
 
     test('after stopped wait period, send a "typing stopped" notice', () => awaitFakeAsync((async) async {
@@ -355,7 +355,7 @@ void main() {
 
       connection.prepare(json: {});
       async.elapse(store.serverTypingStoppedWaitPeriod);
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
       check(async.pendingTimers).isEmpty();
     }));
 
@@ -364,7 +364,7 @@ void main() {
 
       connection.prepare(json: {});
       model.stoppedComposing();
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
 
       async.elapse(Duration.zero);
       check(async.pendingTimers).isEmpty();
@@ -375,19 +375,19 @@ void main() {
 
       connection.prepare(json: {});
       model.stoppedComposing();
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
 
       // The "typing started" notice would have been throttled if we did not
       // reset the TypingNotifier internal states before sending the "typing
       // stopped" notice.
       connection.prepare(json: {});
       model.keystroke(narrow);
-      checkTypingRequest(TypingOp.start, narrow);
+      checkTypingRequest(.start, narrow);
 
       // Ensures that a "typing stopped" notice is sent when the test ends.
       connection.prepare(json: {});
       async.flushTimers();
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     }));
 
     test('disposing store cancels the idle timer', () => awaitFakeAsync((async) async {
@@ -411,7 +411,7 @@ void main() {
       // t = 0ms: Start typing. The idle timer is set to typingStoppedWaitPeriod.
       connection.prepare(json: {});
       model.keystroke(topicNarrow);
-      checkTypingRequest(TypingOp.start, topicNarrow);
+      checkTypingRequest(.start, topicNarrow);
 
       async.elapse(Duration.zero);
       check(async.pendingTimers).single;
@@ -424,7 +424,7 @@ void main() {
       connection.prepare(json: {});
       model.keystroke(dmNarrow);
       checkSetTypingStatusRequests(connection.takeRequests(),
-        [(TypingOp.stop, topicNarrow), (TypingOp.start, dmNarrow)]);
+        [(.stop, topicNarrow), (.start, dmNarrow)]);
 
       async.elapse(Duration.zero);
       check(async.pendingTimers).single;
@@ -440,7 +440,7 @@ void main() {
       async.elapse(waitTime);
       // t = typingStoppedPeriod + 100ms:
       //   The new timer has expired, and a "typing stopped" notice is expected.
-      checkTypingRequest(TypingOp.stop, dmNarrow);
+      checkTypingRequest(.stop, dmNarrow);
     }));
 
     test('start typing in a different destination resets typing started wait timeout', () => awaitFakeAsync((async) async {
@@ -457,7 +457,7 @@ void main() {
       // t = 0ms: Start typing. The typing started time is set to 0ms.
       connection.prepare(json: {});
       model.keystroke(topicNarrow);
-      checkTypingRequest(TypingOp.start, topicNarrow);
+      checkTypingRequest(.start, topicNarrow);
 
       async.elapse(waitInterval);
       // t = waitInterval * 1:
@@ -469,7 +469,7 @@ void main() {
       connection.prepare(json: {});
       model.keystroke(dmNarrow);
       checkSetTypingStatusRequests(connection.takeRequests(),
-        [(TypingOp.stop, topicNarrow), (TypingOp.start, dmNarrow)]);
+        [(.stop, topicNarrow), (.start, dmNarrow)]);
 
       while (async.elapsed <= store.serverTypingStartedWaitPeriod) {
         // t <= typingStartedWaitPeriod: "still typing" requests are throttled.
@@ -494,12 +494,12 @@ void main() {
       //   enough time since the last time we sent a "typing started" notice.
       connection.prepare(json: {});
       model.keystroke(dmNarrow);
-      checkTypingRequest(TypingOp.start, dmNarrow);
+      checkTypingRequest(.start, dmNarrow);
 
       // Ensures that a "typing stopped" notice is sent when the test ends.
       connection.prepare(json: {});
       async.flushTimers();
-      checkTypingRequest(TypingOp.stop, dmNarrow);
+      checkTypingRequest(.stop, dmNarrow);
     }));
   });
 }
diff --git a/test/model/unreads_test.dart b/test/model/unreads_test.dart
index 1d5261311..81ff3c5ec 100644
--- a/test/model/unreads_test.dart
+++ b/test/model/unreads_test.dart
@@ -855,7 +855,7 @@ void main() {
         final event = switch (message) {
           StreamMessage() => DeleteMessageEvent(
             id: 0,
-            messageType: MessageType.stream,
+            messageType: .channel,
             messageIds: [message.id],
             streamId: message.streamId,
             topic: () {
@@ -867,7 +867,7 @@ void main() {
           ),
           DmMessage() => DeleteMessageEvent(
             id: 0,
-            messageType: MessageType.direct,
+            messageType: .direct,
             messageIds: [message.id],
             streamId: null,
             topic: null,
@@ -888,7 +888,7 @@ void main() {
       model.handleDeleteMessageEvent(DeleteMessageEvent(
         id: 0,
         messageIds: [11, 12],
-        messageType: MessageType.stream,
+        messageType: .channel,
         streamId: stream1.streamId,
         topic: eg.t('a'),
       ));
@@ -897,7 +897,7 @@ void main() {
       model.handleDeleteMessageEvent(DeleteMessageEvent(
         id: 0,
         messageIds: [13, 14],
-        messageType: MessageType.stream,
+        messageType: .channel,
         streamId: stream2.streamId,
         topic: eg.t('b'),
       ));
@@ -906,7 +906,7 @@ void main() {
       model.handleDeleteMessageEvent(DeleteMessageEvent(
         id: 0,
         messageIds: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
-        messageType: MessageType.direct,
+        messageType: .direct,
         streamId: null,
         topic: null,
       ));
@@ -922,7 +922,7 @@ void main() {
       model.handleDeleteMessageEvent(DeleteMessageEvent(
         id: 0,
         messageIds: [message.id],
-        messageType: MessageType.stream,
+        messageType: .channel,
         streamId: message.streamId,
         topic: message.topic,
       ));
@@ -941,7 +941,7 @@ void main() {
       model.handleDeleteMessageEvent(DeleteMessageEvent(
         id: 0,
         messageIds: [message.id],
-        messageType: MessageType.direct,
+        messageType: .direct,
         streamId: null,
         topic: null,
       ));
@@ -1373,7 +1373,7 @@ void main() {
             messages: [message1.id, message2.id, message3.id, message4.id],
             messageDetails: {
               message1.id: UpdateMessageFlagsMessageDetail(
-                type: MessageType.stream,
+                type: .channel,
                 mentioned: false,
                 streamId: stream.streamId,
                 topic: eg.t(topic),
@@ -1381,7 +1381,7 @@ void main() {
               ),
               // message 2 and 3 have their details missing
               message4.id: UpdateMessageFlagsMessageDetail(
-                type: MessageType.direct,
+                type: .direct,
                 mentioned: false,
                 streamId: null,
                 topic: null,
diff --git a/test/widgets/action_sheet_test.dart b/test/widgets/action_sheet_test.dart
index 519715ddd..fe3bb1c51 100644
--- a/test/widgets/action_sheet_test.dart
+++ b/test/widgets/action_sheet_test.dart
@@ -81,7 +81,7 @@ Future<void> setupToMessageActionSheet(WidgetTester tester, {
   assert(narrow.containsMessage(message)!);
 
   selfUser ??= eg.selfUser;
-  assert(!(hasDeletePermission && selfUser.role == UserRole.guest));
+  assert(!(hasDeletePermission && selfUser.role == .guest));
   final selfAccount = eg.account(user: selfUser,
     zulipFeatureLevel: zulipFeatureLevel);
   await testBinding.globalStore.add(
@@ -334,7 +334,7 @@ void main() {
           await store.handleEvent(ChannelUpdateEvent(id: 1,
             streamId: someChannel.streamId,
             name: someChannel.name,
-            property: null, value: null,
+            property: .unknown, value: null,
             // (Ideally we'd use `property` and `value` but I'm not sure if
             // modern servers actually do that or if they still use this
             // separate field.)
@@ -349,7 +349,7 @@ void main() {
         testWidgets('private channel', (tester) async {
           await prepare();
           await store.handleEvent(eg.channelUpdateEvent(someChannel,
-            property: ChannelPropertyName.inviteOnly, value: true));
+            property: .inviteOnly, value: true));
           check(store.streams[someChannel.streamId]).isNotNull()
             ..inviteOnly.isTrue()..isWebPublic.isFalse();
           await showFromInbox(tester);
@@ -433,9 +433,9 @@ void main() {
         await prepare();
         await store.addStream(privateChannel);
         await store.updateChannel(privateChannel.streamId,
-          ChannelPropertyName.canSubscribeGroup, eg.groupSetting(members: []));
+          .canSubscribeGroup, eg.groupSetting(members: []));
         await store.updateChannel(privateChannel.streamId,
-          ChannelPropertyName.canAddSubscribersGroup, eg.groupSetting(members: []));
+          .canAddSubscribersGroup, eg.groupSetting(members: []));
         final narrow = ChannelNarrow(privateChannel.streamId);
         check(store.selfHasContentAccess(privateChannel)).isFalse();
         await showFromMsglistAppBar(tester,
@@ -2159,16 +2159,16 @@ void main() {
         });
 
         testWidgets('no error if user lost posting permission after action sheet opened', (tester) async {
-          final selfUser = eg.user(role: UserRole.member);
+          final selfUser = eg.user(role: .member);
           final stream = eg.stream();
           final message = eg.streamMessage(stream: stream);
           await setupToMessageActionSheet(tester, selfUser: selfUser,
             message: message, narrow: TopicNarrow.ofMessage(message));
 
           await store.handleEvent(RealmUserUpdateEvent(id: 1, userId: selfUser.userId,
-            role: UserRole.guest));
+            role: .guest));
           await store.handleEvent(eg.channelUpdateEvent(stream,
-            property: ChannelPropertyName.channelPostPolicy,
+            property: .channelPostPolicy,
             value: ChannelPostPolicy.administrators));
           await tester.pump();
 
diff --git a/test/widgets/autocomplete_test.dart b/test/widgets/autocomplete_test.dart
index 5dd47fc50..38ff30023 100644
--- a/test/widgets/autocomplete_test.dart
+++ b/test/widgets/autocomplete_test.dart
@@ -486,7 +486,7 @@ void main() {
       final composeInputFinder = await setupToComposeInput(tester);
       final store = await testBinding.globalStore.perAccount(eg.selfAccount.id);
       await store.handleEvent(UserSettingsUpdateEvent(id: 1,
-        property: UserSettingName.emojiset, value: Emojiset.text));
+        property: .emojiset, value: Emojiset.text));
 
       // TODO(#226): Remove this extra edit when this bug is fixed.
       await tester.enterText(composeInputFinder, 'hi :');
diff --git a/test/widgets/compose_box_test.dart b/test/widgets/compose_box_test.dart
index 22dfeecc3..d47eb555e 100644
--- a/test/widgets/compose_box_test.dart
+++ b/test/widgets/compose_box_test.dart
@@ -759,7 +759,7 @@ void main() {
 
       Future<void> changePolicy(ChannelTopicsPolicy value) async {
         await store.handleEvent(eg.channelUpdateEvent(store.streams[channel.streamId]!,
-          property: ChannelPropertyName.topicsPolicy, value: value));
+          property: .topicsPolicy, value: value));
         await tester.pump();
       }
 
@@ -789,7 +789,7 @@ void main() {
         .topic.text.equals('some topic');
 
       await store.handleEvent(eg.channelUpdateEvent(store.streams[channel.streamId]!,
-        property: ChannelPropertyName.topicsPolicy,
+        property: .topicsPolicy,
         value: ChannelTopicsPolicy.emptyTopicOnly));
       await tester.pump(Duration.zero);
       check(state).controller.isA<StreamComposeBoxController>()
@@ -845,7 +845,7 @@ void main() {
     Future<void> checkStartTyping(WidgetTester tester, SendableNarrow narrow) async {
       connection.prepare(json: {});
       await enterContent(tester, 'hello world');
-      checkTypingRequest(TypingOp.start, narrow);
+      checkTypingRequest(.start, narrow);
     }
 
     testWidgets('smoke TopicNarrow', (tester) async {
@@ -856,7 +856,7 @@ void main() {
 
       connection.prepare(json: {});
       await tester.pump(store.serverTypingStoppedWaitPeriod);
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     });
 
     testWidgets('smoke DmNarrow', (tester) async {
@@ -868,7 +868,7 @@ void main() {
 
       connection.prepare(json: {});
       await tester.pump(store.serverTypingStoppedWaitPeriod);
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     });
 
     testWidgets('smoke ChannelNarrow', (tester) async {
@@ -882,7 +882,7 @@ void main() {
 
       connection.prepare(json: {});
       await tester.pump(store.serverTypingStoppedWaitPeriod);
-      checkTypingRequest(TypingOp.stop, destinationNarrow);
+      checkTypingRequest(.stop, destinationNarrow);
     });
 
     testWidgets('clearing text sends a "typing stopped" notice', (tester) async {
@@ -893,7 +893,7 @@ void main() {
 
       connection.prepare(json: {});
       await enterContent(tester, '');
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     });
 
     testWidgets('hitting send button sends a "typing stopped" notice', (tester) async {
@@ -909,7 +909,7 @@ void main() {
       await tester.tap(sendButtonFinder);
       await tester.pump(Duration.zero);
       final requests = connection.takeRequests();
-      checkSetTypingStatusRequests([requests.first], [(TypingOp.stop, narrow)]);
+      checkSetTypingStatusRequests([requests.first], [(.stop, narrow)]);
       check(requests).length.equals(2);
     });
 
@@ -940,7 +940,7 @@ void main() {
       connection.prepare(json: {});
       (await ZulipApp.navigator).pop();
       await tester.pump(Duration.zero);
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     });
 
     testWidgets('for content input, unfocusing sends a "typing stopped" notice', (tester) async {
@@ -955,7 +955,7 @@ void main() {
       connection.prepare(json: {});
       FocusManager.instance.primaryFocus!.unfocus();
       await tester.pump(Duration.zero);
-      checkTypingRequest(TypingOp.stop, destinationNarrow);
+      checkTypingRequest(.stop, destinationNarrow);
     });
 
     testWidgets('selection change sends a "typing started" notice', (tester) async {
@@ -966,17 +966,17 @@ void main() {
 
       connection.prepare(json: {});
       await tester.pump(store.serverTypingStoppedWaitPeriod);
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
 
       connection.prepare(json: {});
       controller!.content.selection =
         const TextSelection(baseOffset: 0, extentOffset: 2);
-      checkTypingRequest(TypingOp.start, narrow);
+      checkTypingRequest(.start, narrow);
 
       // Ensures that a "typing stopped" notice is sent when the test ends.
       connection.prepare(json: {});
       await tester.pump(store.serverTypingStoppedWaitPeriod);
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
     });
 
     testWidgets('unfocusing app sends a "typing stopped" notice', (tester) async {
@@ -994,7 +994,7 @@ void main() {
       WidgetsBinding.instance.handleAppLifecycleStateChanged(
         AppLifecycleState.hidden);
       await tester.pump(Duration.zero);
-      checkTypingRequest(TypingOp.stop, narrow);
+      checkTypingRequest(.stop, narrow);
 
       WidgetsBinding.instance.handleAppLifecycleStateChanged(
         AppLifecycleState.paused);
@@ -1027,7 +1027,7 @@ void main() {
         ..method.equals('POST')
         ..url.path.equals('/api/v1/messages')
         ..bodyFields.deepEquals({
-            'type': 'stream',
+            'type': 'channel',
             'to': '123',
             'topic': 'some topic',
             'content': 'hello world',
@@ -1734,7 +1734,7 @@ void main() {
           await prepareComposeBox(tester,
             narrow: narrow,
             selfUser: eg.user(
-              role: canSend ? UserRole.administrator : UserRole.member),
+              role: canSend ? .administrator : .member),
             streams: [channel],
             subscriptions: isChannelSubscribed ? [eg.subscription(channel)] : []);
           checkComposeBoxIsShown(expected,
@@ -1840,7 +1840,7 @@ void main() {
       testRefreshSubscribeButtons(narrow: topicNarrow, canSendMessages: true);
 
       testWidgets('user loses privilege -> compose box is replaced with the banner', (tester) async {
-        final selfUser = eg.user(role: UserRole.administrator);
+        final selfUser = eg.user(role: .administrator);
         await prepareComposeBox(tester,
           narrow: const ChannelNarrow(1),
           selfUser: selfUser,
@@ -1849,13 +1849,13 @@ void main() {
         checkComposeBox(isShown: true);
 
         await store.handleEvent(RealmUserUpdateEvent(id: 1,
-          userId: selfUser.userId, role: UserRole.moderator));
+          userId: selfUser.userId, role: .moderator));
         await tester.pump();
         checkComposeBox(isShown: false);
       });
 
       testWidgets('user gains privilege -> banner is replaced with the compose box', (tester) async {
-        final selfUser = eg.user(role: UserRole.guest);
+        final selfUser = eg.user(role: .guest);
         await prepareComposeBox(tester,
           narrow: const ChannelNarrow(1),
           selfUser: selfUser,
@@ -1864,13 +1864,13 @@ void main() {
         checkComposeBox(isShown: false);
 
         await store.handleEvent(RealmUserUpdateEvent(id: 1,
-          userId: selfUser.userId, role: UserRole.administrator));
+          userId: selfUser.userId, role: .administrator));
         await tester.pump();
         checkComposeBox(isShown: true);
       });
 
       testWidgets('channel policy becomes stricter -> compose box is replaced with the banner', (tester) async {
-        final selfUser = eg.user(role: UserRole.guest);
+        final selfUser = eg.user(role: .guest);
         final channel = eg.stream(streamId: 1,
           channelPostPolicy: ChannelPostPolicy.any);
 
@@ -1881,14 +1881,14 @@ void main() {
         checkComposeBox(isShown: true);
 
         await store.handleEvent(eg.channelUpdateEvent(channel,
-          property: ChannelPropertyName.channelPostPolicy,
+          property: .channelPostPolicy,
           value: ChannelPostPolicy.fullMembers));
         await tester.pump();
         checkComposeBox(isShown: false);
       });
 
       testWidgets('channel policy becomes less strict -> banner is replaced with the compose box', (tester) async {
-        final selfUser = eg.user(role: UserRole.moderator);
+        final selfUser = eg.user(role: .moderator);
         final channel = eg.stream(streamId: 1,
           channelPostPolicy: ChannelPostPolicy.administrators);
 
@@ -1899,7 +1899,7 @@ void main() {
         checkComposeBox(isShown: false);
 
         await store.handleEvent(eg.channelUpdateEvent(channel,
-          property: ChannelPropertyName.channelPostPolicy,
+          property: .channelPostPolicy,
           value: ChannelPostPolicy.moderators));
         await tester.pump();
         checkComposeBox(isShown: true);
@@ -2062,7 +2062,7 @@ void main() {
         .topic.text.equals('some topic');
 
       await newStore.handleEvent(eg.channelUpdateEvent(newStore.streams[channel.streamId]!,
-        property: ChannelPropertyName.topicsPolicy,
+        property: .topicsPolicy,
         value: ChannelTopicsPolicy.emptyTopicOnly));
       await tester.pump(Duration.zero);
       check(state).controller.isA<StreamComposeBoxController>()
@@ -2238,7 +2238,7 @@ void main() {
         ..content.text.isNotNull().isEmpty();
 
       await store.handleEvent(eg.channelUpdateEvent(store.streams[channel.streamId]!,
-        property: ChannelPropertyName.topicsPolicy,
+        property: .topicsPolicy,
         value: ChannelTopicsPolicy.emptyTopicOnly));
       await tester.pump(Duration.zero);
 
diff --git a/test/widgets/content_test.dart b/test/widgets/content_test.dart
index 77eaadecb..7f9e4002f 100644
--- a/test/widgets/content_test.dart
+++ b/test/widgets/content_test.dart
@@ -1594,7 +1594,7 @@ void main() {
 
     Future<void> prepare(
       WidgetTester tester,
-      [TwentyFourHourTimeMode twentyFourHourTimeMode = TwentyFourHourTimeMode.localeDefault]
+      [TwentyFourHourTimeMode twentyFourHourTimeMode = .localeDefault]
     ) async {
       final initialSnapshot = eg.initialSnapshot()
         ..userSettings.twentyFourHourTime = twentyFourHourTimeMode;
@@ -1611,17 +1611,17 @@ void main() {
     });
 
     testWidgets('TwentyFourHourTimeMode.twelveHour', (tester) async {
-      await prepare(tester, TwentyFourHourTimeMode.twelveHour);
+      await prepare(tester, .twelveHour);
       check(find.textContaining(renderedTextRegexpTwelveHour)).findsOne();
     });
 
     testWidgets('TwentyFourHourTimeMode.twentyFourHour', (tester) async {
-      await prepare(tester, TwentyFourHourTimeMode.twentyFourHour);
+      await prepare(tester, .twentyFourHour);
       check(find.textContaining(renderedTextRegexpTwentyFourHour)).findsOne();
     });
 
     testWidgets('TwentyFourHourTimeMode.localeDefault', (tester) async {
-      await prepare(tester, TwentyFourHourTimeMode.localeDefault);
+      await prepare(tester, .localeDefault);
       // This expectation holds as long as we're always formatting in en_US,
       // the default locale, which uses the twelve-hour format.
       // TODO(#1727) follow the actual locale; test with different locales
diff --git a/test/widgets/emoji_reaction_test.dart b/test/widgets/emoji_reaction_test.dart
index 72ccac41a..233b964f5 100644
--- a/test/widgets/emoji_reaction_test.dart
+++ b/test/widgets/emoji_reaction_test.dart
@@ -143,7 +143,7 @@ void main() {
   group('ReactionChipsList', () {
     // Smoke tests under various conditions.
     for (final displayEmojiReactionUsers in [true, false]) {
-      for (final emojiset in [Emojiset.text, Emojiset.google]) {
+      for (final emojiset in <Emojiset>[.text, .google]) {
         for (final textDirection in TextDirection.values) {
           for (final textScaleFactor in kTextScaleFactors) {
             void runSmokeTest(
@@ -190,10 +190,10 @@ void main() {
                 await store.handleEvent(RealmEmojiUpdateEvent(id: 1,
                   realmEmoji: realmEmoji));
                 await store.handleEvent(UserSettingsUpdateEvent(id: 1,
-                  property: UserSettingName.displayEmojiReactionUsers,
+                  property: .displayEmojiReactionUsers,
                   value: displayEmojiReactionUsers));
                 await store.handleEvent(UserSettingsUpdateEvent(id: 1,
-                  property: UserSettingName.emojiset,
+                  property: .emojiset,
                   value: emojiset));
 
                 // This does mean that all image emoji will look the same…
diff --git a/test/widgets/home_test.dart b/test/widgets/home_test.dart
index 31f2f4a78..ae49fa47e 100644
--- a/test/widgets/home_test.dart
+++ b/test/widgets/home_test.dart
@@ -760,7 +760,7 @@ void main () {
       await prepareBanner(tester,
         zulipFeatureLevel: unsupportedFeatureLevel,
         zulipVersion: unsupportedVersion,
-        selfUser: eg.user(role: UserRole.administrator));
+        selfUser: eg.user(role: .administrator));
       check(find.text(zulipLocalizations.serverCompatBannerAdminMessage(
         sampleRealmUrl, unsupportedVersion))).findsOne();
     });
@@ -769,7 +769,7 @@ void main () {
       await prepareBanner(tester,
         zulipFeatureLevel: unsupportedFeatureLevel,
         zulipVersion: unsupportedVersion,
-        selfUser: eg.user(role: UserRole.owner));
+        selfUser: eg.user(role: .owner));
       check(find.text(zulipLocalizations.serverCompatBannerAdminMessage(
         sampleRealmUrl, unsupportedVersion))).findsOne();
     });
diff --git a/test/widgets/message_list_test.dart b/test/widgets/message_list_test.dart
index f703aae43..afa6b451a 100644
--- a/test/widgets/message_list_test.dart
+++ b/test/widgets/message_list_test.dart
@@ -1176,19 +1176,19 @@ void main() {
         await tester.pump();
         check(finder.evaluate()).isEmpty();
         await checkTyping(tester,
-          eg.typingEvent(narrow, TypingOp.start, eg.otherUser.userId),
+          eg.typingEvent(narrow, .start, eg.otherUser.userId),
           expected: 'Other User is typing…');
         await checkTyping(tester,
-          eg.typingEvent(narrow, TypingOp.start, eg.selfUser.userId),
+          eg.typingEvent(narrow, .start, eg.selfUser.userId),
           expected: 'Other User is typing…');
         await checkTyping(tester,
-          eg.typingEvent(narrow, TypingOp.start, eg.thirdUser.userId),
+          eg.typingEvent(narrow, .start, eg.thirdUser.userId),
           expected: 'Other User and Third User are typing…');
         await checkTyping(tester,
-          eg.typingEvent(narrow, TypingOp.start, eg.fourthUser.userId),
+          eg.typingEvent(narrow, .start, eg.fourthUser.userId),
           expected: 'Several people are typing…');
         await checkTyping(tester,
-          eg.typingEvent(narrow, TypingOp.stop, eg.otherUser.userId),
+          eg.typingEvent(narrow, .stop, eg.otherUser.userId),
           expected: 'Third User and Fourth User are typing…');
         // Verify that typing indicators expire after a set duration.
         await tester.pump(const Duration(seconds: 15));
@@ -1202,7 +1202,7 @@ void main() {
       await setupMessageListPage(tester,
         narrow: narrow, users: [], messages: [streamMessage]);
       await checkTyping(tester,
-        eg.typingEvent(narrow, TypingOp.start, 1000),
+        eg.typingEvent(narrow, .start, 1000),
         expected: '(unknown user) is typing…',
       );
       // Wait for the pending timers to end.
@@ -1214,18 +1214,18 @@ void main() {
         narrow: topicNarrow, users: users, messages: [streamMessage]);
 
       await checkTyping(tester,
-        eg.typingEvent(topicNarrow, TypingOp.start, eg.otherUser.userId),
+        eg.typingEvent(topicNarrow, .start, eg.otherUser.userId),
         expected: 'Other User is typing…');
 
       await checkTyping(tester,
-        eg.typingEvent(topicNarrow, TypingOp.start, eg.thirdUser.userId),
+        eg.typingEvent(topicNarrow, .start, eg.thirdUser.userId),
         expected: 'Other User and Third User are typing…');
 
       await store.setMutedUsers([eg.otherUser.userId]);
       await tester.pump();
 
       await checkTyping(tester,
-        eg.typingEvent(topicNarrow, TypingOp.start, eg.thirdUser.userId),
+        eg.typingEvent(topicNarrow, .start, eg.thirdUser.userId),
         expected: 'Third User is typing…', // no "Other User"
       );
 
@@ -1681,7 +1681,7 @@ void main() {
         ..method.equals('POST')
         ..url.path.equals('/api/v1/messages')
         ..bodyFields.deepEquals({
-          'type': 'stream',
+          'type': 'channel',
           'to': '${otherChannel.streamId}',
           'topic': 'new topic',
           'content': 'Some text',
@@ -2167,12 +2167,12 @@ void main() {
       for (final (timestampStr, expectedTwelveHour, expectedTwentyFourHour) in cases) {
         for (final mode in TwentyFourHourTimeMode.values) {
           final expected = switch (mode) {
-            TwentyFourHourTimeMode.twelveHour => expectedTwelveHour,
-            TwentyFourHourTimeMode.twentyFourHour => expectedTwentyFourHour,
+            .twelveHour => expectedTwelveHour,
+            .twentyFourHour => expectedTwentyFourHour,
             // This expectation will hold as long as we're always using the
             // default locale, en_US, which uses the twelve-hour format.
             // TODO(#1727) test with other locales
-            TwentyFourHourTimeMode.localeDefault => expectedTwelveHour,
+            .localeDefault => expectedTwelveHour,
           };
 
           test('${style.name} in ${mode.name}: $timestampStr returns $expected', () {
diff --git a/test/widgets/profile_test.dart b/test/widgets/profile_test.dart
index c21361909..801188c34 100644
--- a/test/widgets/profile_test.dart
+++ b/test/widgets/profile_test.dart
@@ -219,16 +219,16 @@ void main() {
         ],
         pageUserId: 1,
         customProfileFields: [
-          eg.customProfileField(0, CustomProfileFieldType.shortText),
-          eg.customProfileField(1, CustomProfileFieldType.longText),
-          eg.customProfileField(2, CustomProfileFieldType.choice,
+          eg.customProfileField(0, .shortText),
+          eg.customProfileField(1, .longText),
+          eg.customProfileField(2, .choice,
             fieldData: '{"x": {"text": "choiceValue", "order": "1"}}'),
-          eg.customProfileField(3, CustomProfileFieldType.date),
-          eg.customProfileField(4, CustomProfileFieldType.link),
-          eg.customProfileField(5, CustomProfileFieldType.user),
-          eg.customProfileField(6, CustomProfileFieldType.externalAccount,
+          eg.customProfileField(3, .date),
+          eg.customProfileField(4, .link),
+          eg.customProfileField(5, .user),
+          eg.customProfileField(6, .externalAccount,
             fieldData: '{"subtype": "external1"}'),
-          eg.customProfileField(7, CustomProfileFieldType.pronouns),
+          eg.customProfileField(7, .pronouns),
         ], realmDefaultExternalAccounts: {
           'external1': RealmDefaultExternalAccount(
             name: 'external1',
@@ -236,15 +236,15 @@ void main() {
             hint: '',
             urlPattern: 'https://example/%(username)s')});
 
-      final testCases = [
-        (find.text('field0'), find.text('shortTextValue'), CustomProfileFieldType.shortText),
-        (find.text('field1'), find.text('longTextValue'), CustomProfileFieldType.longText),
-        (find.text('field2'), find.text('choiceValue'), CustomProfileFieldType.choice),
-        (find.text('field3'), find.text('dateValue'), CustomProfileFieldType.date),
-        (find.text('field4'), find.text('http://example/linkValue'), CustomProfileFieldType.link),
-        (find.text('field5'), find.text('userValue'), CustomProfileFieldType.user),
-        (find.text('field6'), find.text('externalValue'), CustomProfileFieldType.externalAccount),
-        (find.text('field7'), find.text('pronounsValue'), CustomProfileFieldType.pronouns),
+      final testCases = <(Finder, Finder, CustomProfileFieldType)>[
+        (find.text('field0'), find.text('shortTextValue'), .shortText),
+        (find.text('field1'), find.text('longTextValue'), .longText),
+        (find.text('field2'), find.text('choiceValue'), .choice),
+        (find.text('field3'), find.text('dateValue'), .date),
+        (find.text('field4'), find.text('http://example/linkValue'), .link),
+        (find.text('field5'), find.text('userValue'), .user),
+        (find.text('field6'), find.text('externalValue'), .externalAccount),
+        (find.text('field7'), find.text('pronounsValue'), .pronouns),
       ];
       for (final testCase in testCases) {
         Finder labelFinder = testCase.$1;
@@ -273,7 +273,7 @@ void main() {
       await setupPage(tester,
         users: [user],
         pageUserId: user.userId,
-        customProfileFields: [eg.customProfileField(0, CustomProfileFieldType.link)],
+        customProfileFields: [eg.customProfileField(0, .link)],
       );
 
       await tester.tap(find.text(testUrl));
@@ -292,7 +292,7 @@ void main() {
         users: [user],
         pageUserId: user.userId,
         customProfileFields: [
-          eg.customProfileField(0, CustomProfileFieldType.externalAccount,
+          eg.customProfileField(0, .externalAccount,
             fieldData: '{"subtype": "external1"}')
         ],
         realmDefaultExternalAccounts: {
@@ -324,7 +324,7 @@ void main() {
       await setupPage(tester,
         users: users,
         pageUserId: 1,
-        customProfileFields: [eg.customProfileField(0, CustomProfileFieldType.user)],
+        customProfileFields: [eg.customProfileField(0, .user)],
         navigatorObserver: testNavObserver,
       );
 
@@ -345,7 +345,7 @@ void main() {
       await setupPage(tester,
         users: users,
         pageUserId: 1,
-        customProfileFields: [eg.customProfileField(0, CustomProfileFieldType.user)],
+        customProfileFields: [eg.customProfileField(0, .user)],
       );
 
       final textFinder = find.text('(unknown user)');
@@ -376,7 +376,7 @@ void main() {
         users: users,
         mutedUserIds: [2],
         pageUserId: 1,
-        customProfileFields: [eg.customProfileField(0, CustomProfileFieldType.user)]);
+        customProfileFields: [eg.customProfileField(0, .user)]);
 
       check(find.text('Muted user')).findsOne();
       check(mutedAvatarFinder(2)).findsOne();
@@ -401,7 +401,7 @@ void main() {
       await setupPage(tester,
         users: users,
         pageUserId: 1,
-        customProfileFields: [eg.customProfileField(0, CustomProfileFieldType.user)],
+        customProfileFields: [eg.customProfileField(0, .user)],
       );
 
       final avatars = tester.widgetList<Avatar>(find.byType(Avatar));
@@ -424,16 +424,16 @@ void main() {
 
       await setupPage(tester, users: [user, user2], pageUserId: user.userId,
         customProfileFields: [
-          eg.customProfileField(0, CustomProfileFieldType.shortText),
-          eg.customProfileField(1, CustomProfileFieldType.longText),
-          eg.customProfileField(2, CustomProfileFieldType.choice,
+          eg.customProfileField(0, .shortText),
+          eg.customProfileField(1, .longText),
+          eg.customProfileField(2, .choice,
             fieldData: '{"x": {"text": "$longString", "order": "1"}}'),
           // no [CustomProfileFieldType.date] because those can't be made long
-          eg.customProfileField(3, CustomProfileFieldType.link),
-          eg.customProfileField(4, CustomProfileFieldType.user),
-          eg.customProfileField(5, CustomProfileFieldType.externalAccount,
+          eg.customProfileField(3, .link),
+          eg.customProfileField(4, .user),
+          eg.customProfileField(5, .externalAccount,
             fieldData: '{"subtype": "external1"}'),
-          eg.customProfileField(6, CustomProfileFieldType.pronouns),
+          eg.customProfileField(6, .pronouns),
         ], realmDefaultExternalAccounts: {
           'external1': RealmDefaultExternalAccount(
             name: 'external1',
@@ -565,7 +565,7 @@ void main() {
     void scheduleEventAfter(Duration duration, bool newInvisibleModeValue) async {
       await Future<void>.delayed(duration);
       await store.handleEvent(UserSettingsUpdateEvent(id: 1,
-        property: UserSettingName.presenceEnabled, value: !newInvisibleModeValue));
+        property: .presenceEnabled, value: !newInvisibleModeValue));
     }
 
     void checkRequest(bool requestedInvisibleModeValue) {
@@ -619,7 +619,7 @@ void main() {
       checkAppearsActive(tester, false);
 
       await store.handleEvent(UserSettingsUpdateEvent(id: 1,
-        property: UserSettingName.presenceEnabled, value: false));
+        property: .presenceEnabled, value: false));
       await tester.pump();
       checkAppearsActive(tester, true);
 
@@ -654,7 +654,7 @@ void main() {
 
       await setupPage(tester, pageUserId: eg.selfUser.userId);
       await store.handleEvent(UserSettingsUpdateEvent(id: 1,
-        property: UserSettingName.presenceEnabled, value: false));
+        property: .presenceEnabled, value: false));
       await tester.pump();
       checkAppearsActive(tester, true);