From ca682b0df4a89c96957ac7adbc684900adcc1e63 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mateusz=20Burzy=C5=84ski?= <mateuszburzynski@gmail.com>
Date: Fri, 31 Oct 2025 11:53:26 +0100
Subject: [PATCH 1/3] Fixed inference for generic `Type`s when argument has
 `Default` property

---
 ark/type/variants/base.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/ark/type/variants/base.ts b/ark/type/variants/base.ts
index 95df88bdf2..20deb6e5c1 100644
--- a/ark/type/variants/base.ts
+++ b/ark/type/variants/base.ts
@@ -637,7 +637,10 @@ interface Type<out t = unknown, $ = {}>
 	): reduceOut
 
 	/** The Type's [StandardSchema](https://github.com/standard-schema/standard-schema) properties */
-	"~standard": StandardSchemaV1.ArkTypeProps<this["inferIn"], this["inferOut"]>
+	"~standard": StandardSchemaV1.ArkTypeProps<
+		NoInfer<this["inferIn"]>,
+		NoInfer<this["inferOut"]>
+	>
 
 	// deprecate Function methods so they are deprioritized as suggestions
 

From 18238796b214cfe470b1fc03f5ac9567553b02a3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mateusz=20Burzy=C5=84ski?= <mateuszburzynski@gmail.com>
Date: Thu, 6 Nov 2025 23:31:50 +0100
Subject: [PATCH 2/3] add tests

---
 ark/type/__tests__/realWorld.test.ts | 34 +++++++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/ark/type/__tests__/realWorld.test.ts b/ark/type/__tests__/realWorld.test.ts
index 61c64de3fb..13af24ec9b 100644
--- a/ark/type/__tests__/realWorld.test.ts
+++ b/ark/type/__tests__/realWorld.test.ts
@@ -4,7 +4,7 @@ import {
 	type ArkErrors,
 	type StandardSchemaV1
 } from "@ark/schema"
-import { scope, type, type Module } from "arktype"
+import { scope, type, type Module, type Type } from "arktype"
 import type { Out, To } from "arktype/internal/attributes.ts"
 
 declare class TimeStub {
@@ -1366,4 +1366,36 @@ Right: { x: number, y: number, + (undeclared): delete }`)
 			'{ masterItem: true, minPrice: number % 1 & >= 0, qualities: (1 | 2 | 3 | 4 | 5)[] | [null], short: string, skin: string, type: "skin", souvenirAvailable: boolean = false, stattrakAvailable: boolean = false, + (undeclared): reject } | { short: string, skin: string, type: "skin", souvenir: boolean = false, stattrak: boolean = false, quality?: 1 | 2 | 3 | 4 | 5, weight?: number, + (undeclared): reject }'
 		)
 	})
+
+	it("allows inferring a schema's type argument in a generic wrapper function when the type uses Default", () => {
+		function someFunction<TSchema extends Record<string, any>>(
+			schema: Type<TSchema, {}>
+		): (typeof schema)["infer"] {
+			const someData = { hello: "world" }
+			return schema.assert(someData)
+		}
+
+		const schema = type({
+			hello: type("string").pipe(s => s === "world"),
+			goodbye: "string='blah'"
+		})
+
+		someFunction(schema)
+	})
+
+	it("allows inferring a schema in a generic wrapper function when the type uses Default", () => {
+		function someFunction<schema extends type.Any<Record<string, any>>>(
+			schema: schema
+		) {
+			const someData = { hello: "world" }
+			return schema.assert(someData)
+		}
+
+		const schema = type({
+			hello: type("string").pipe(s => s === "world"),
+			goodbye: "string='blah'"
+		})
+
+		someFunction(schema)
+	})
 })

From 3306d446367458e25a462af1a3e71f10006f209f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mateusz=20Burzy=C5=84ski?= <mateuszburzynski@gmail.com>
Date: Fri, 7 Nov 2025 10:42:18 +0100
Subject: [PATCH 3/3] use David's trick

---
 ark/type/variants/base.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ark/type/variants/base.ts b/ark/type/variants/base.ts
index 20deb6e5c1..271caec9bb 100644
--- a/ark/type/variants/base.ts
+++ b/ark/type/variants/base.ts
@@ -638,8 +638,8 @@ interface Type<out t = unknown, $ = {}>
 
 	/** The Type's [StandardSchema](https://github.com/standard-schema/standard-schema) properties */
 	"~standard": StandardSchemaV1.ArkTypeProps<
-		NoInfer<this["inferIn"]>,
-		NoInfer<this["inferOut"]>
+		this["inferIn"] extends infer _ ? _ : never,
+		this["inferOut"] extends infer _ ? _ : never
 	>
 
 	// deprecate Function methods so they are deprioritized as suggestions