diff --git a/server/src/compiler_analyzer/analyzer.ts b/server/src/compiler_analyzer/analyzer.ts
index 551f6503..d81b5b55 100644
--- a/server/src/compiler_analyzer/analyzer.ts
+++ b/server/src/compiler_analyzer/analyzer.ts
@@ -90,7 +90,6 @@ import {
     resolvedBuiltinDouble,
     resolvedBuiltinFloat,
     resolvedBuiltinInt,
-    resolvedBuiltinString,
     tryGetBuiltInType
 } from "./symbolBuiltin";
 import {ComplementKind, pushHintOfCompletionScopeToParent} from "./symbolComplement";
@@ -873,7 +872,8 @@ function analyzeLiteral(scope: SymbolScope, literal: NodeLiteral): ResolvedType
     }
 
     if (literalValue.kind === TokenKind.String) {
-        return resolvedBuiltinString;
+        const stringType = scope.getBuiltinStringType();
+        return stringType === undefined ? undefined : new ResolvedType(stringType);
     }
 
     if (literalValue.text === 'true' || literalValue.text === 'false') {
@@ -1306,6 +1306,8 @@ export interface HoistResult {
 export function analyzeAfterHoisted(path: string, hoistResult: HoistResult): AnalyzedScope {
     const {globalScope, analyzeQueue} = hoistResult;
 
+    globalScope.commitContext();
+
     // Analyze the contents of the scope to be processed.
     while (analyzeQueue.length > 0) {
         const next = analyzeQueue.shift();
diff --git a/server/src/compiler_analyzer/checkType.ts b/server/src/compiler_analyzer/checkType.ts
index a1dbff0d..230dce66 100644
--- a/server/src/compiler_analyzer/checkType.ts
+++ b/server/src/compiler_analyzer/checkType.ts
@@ -145,15 +145,6 @@ function canDownCast(
     return false;
 }
 
-// Judge if the class has a metadata that indicates it is a built-in string type.
-function isSourceBuiltinString(source: TypeSourceNode | undefined): boolean {
-    if (source === undefined) return false;
-    if (source.nodeName != NodeName.Class) return false;
-
-    const builtinStringMetadata = "BuiltinString";
-    return source.metadata.length === 1 && source.metadata[0].text === builtinStringMetadata;
-}
-
 function canCastFromPrimitiveType(
     srcType: SymbolType, destType: SymbolType
 ) {
@@ -164,12 +155,6 @@ function canCastFromPrimitiveType(
         return destType.isTypeParameter && isSameToken(srcType.declaredPlace, destType.declaredPlace);
     }
 
-    if (srcType.identifierText === 'string') { // TODO: fix this
-        const destName = destType.declaredPlace.text;
-        if (isSourceBuiltinString(destNode)) return true;
-        return getGlobalSettings().builtinStringTypes.includes(destName);
-    }
-
     if (srcType.identifierText === 'void') {
         return false;
     }
diff --git a/server/src/compiler_analyzer/symbolBuiltin.ts b/server/src/compiler_analyzer/symbolBuiltin.ts
index 2ac249d8..838f197d 100644
--- a/server/src/compiler_analyzer/symbolBuiltin.ts
+++ b/server/src/compiler_analyzer/symbolBuiltin.ts
@@ -24,10 +24,9 @@ const builtinNumberTypeMap: Map<string, SymbolType> = (() => {
     return map;
 })();
 
-// TODO: Remove this?
-export const builtinStringType: SymbolType = createBuiltinType(createVirtualToken(TokenKind.String, 'string'));
+// export const builtinStringType: SymbolType = createBuiltinType(createVirtualToken(TokenKind.String, 'string'));
 
-export const resolvedBuiltinString: ResolvedType = new ResolvedType(builtinStringType);
+// export const resolvedBuiltinString: ResolvedType = new ResolvedType(builtinStringType);
 
 export const builtinIntType = builtinNumberTypeMap.get('int')!;
 
diff --git a/server/src/compiler_analyzer/symbolScope.ts b/server/src/compiler_analyzer/symbolScope.ts
index 75bf0a63..363e045e 100644
--- a/server/src/compiler_analyzer/symbolScope.ts
+++ b/server/src/compiler_analyzer/symbolScope.ts
@@ -2,7 +2,7 @@ import {
     SymbolOwnerNode,
     SymbolFunction,
     SymbolObject,
-    ReferencedSymbolInfo
+    ReferencedSymbolInfo, TypeSourceNode, SymbolType
 } from "./symbolObject";
 import {diagnostic} from "../code/diagnostic";
 import {NodeName} from "../compiler_parser/nodes";
@@ -10,26 +10,35 @@ import {ParserToken} from "../compiler_parser/parserToken";
 import {getPathOfScope} from "./symbolUtils";
 import {ComplementHints} from "./symbolComplement";
 import assert = require("node:assert");
+import {getGlobalSettings} from "../code/settings";
 
 export type ScopeMap = Map<string, SymbolScope>;
 
 export type SymbolMap = Map<string, SymbolObject>;
 
+interface RootScopeContext {
+    builtinStringType: SymbolType | undefined;
+}
+
 /**
  * Represents a scope that contains symbols.
  */
 export class SymbolScope {
+    // A node associated with this scope
     private symbolOwnerNode: SymbolOwnerNode | undefined;
+    // The parent scope of this scope. If this is the root scope (global scope), it has the context for the file.
+    private readonly parentOrContext: SymbolScope | RootScopeContext;
 
     public constructor(
         ownerNode: SymbolOwnerNode | undefined,
-        public readonly parentScope: SymbolScope | undefined,
+        parentScope: SymbolScope | undefined,
         public readonly key: string,
         public readonly childScopes: ScopeMap,
         public readonly symbolMap: SymbolMap,
         public readonly referencedList: ReferencedSymbolInfo[],
         public readonly completionHints: ComplementHints[],
     ) {
+        this.parentOrContext = parentScope ?? {builtinStringType: undefined};
         this.symbolOwnerNode = ownerNode;
     }
 
@@ -48,6 +57,11 @@ export class SymbolScope {
             []);
     }
 
+    public get parentScope(): SymbolScope | undefined {
+        if (this.parentOrContext instanceof SymbolScope) return this.parentOrContext;
+        return undefined;
+    }
+
     public setOwnerNode(ownerNode: SymbolOwnerNode | undefined) {
         assert(this.symbolOwnerNode === undefined);
         this.symbolOwnerNode = ownerNode;
@@ -57,6 +71,44 @@ export class SymbolScope {
         return this.symbolOwnerNode;
     }
 
+    /**
+     * Cache information in the context of the file
+     */
+    public commitContext() {
+        assert(this.parentOrContext instanceof SymbolScope === false);
+        this.parentOrContext.builtinStringType = findBuiltinStringType(this);
+    }
+
+    public getBuiltinStringType(): SymbolType | undefined {
+        if (this.parentOrContext instanceof SymbolScope) return this.parentOrContext.getBuiltinStringType();
+        return this.parentOrContext.builtinStringType;
+    }
+}
+
+function findBuiltinStringType(scope: SymbolScope): SymbolType | undefined {
+    for (const [key, symbol] of scope.symbolMap) {
+        if (symbol instanceof SymbolType && isSourceBuiltinString(symbol.sourceNode)) return symbol;
+    }
+
+    for (const [key, child] of scope.childScopes) {
+        const found = findBuiltinStringType(child);
+        if (found !== undefined) return found;
+    }
+
+    return undefined;
+}
+
+// Judge if the class has a metadata that indicates it is a built-in string type.
+function isSourceBuiltinString(source: TypeSourceNode | undefined): boolean {
+    if (source === undefined) return false;
+    if (source.nodeName != NodeName.Class) return false;
+
+    // Check if the class has a metadata that indicates it is a built-in string type.
+    const builtinStringMetadata = "BuiltinString";
+    if (source.metadata.length === 1 && source.metadata[0].text === builtinStringMetadata) return true;
+
+    // Check whether the class name is a built-in string type with global settings.
+    return getGlobalSettings().builtinStringTypes.includes(source.identifier.text);
 }
 
 export interface SymbolAndScope {