diff --git a/packages/compiler/src/frontend/program.ts b/packages/compiler/src/frontend/program.ts
index 25caecb64..2f1b2f729 100644
--- a/packages/compiler/src/frontend/program.ts
+++ b/packages/compiler/src/frontend/program.ts
@@ -488,43 +488,33 @@ function visitNpmStaticDeclarationClosure(
   visit(entryPath);
 }
 
-function npmStaticDeclarationOverloadsOf(
+/** The overloads and properties of the classes a package's declaration
+ * closure declares, read from one parse of each declaration file. */
+function npmStaticDeclarationMetadataOf(
   services: FrontendServices,
   entryPath: string,
-): NpmStaticDeclarationOverloads {
-  const classes = new Map<string, Map<string, readonly NpmStaticOverloadSignature[]>>();
+): { overloads: NpmStaticDeclarationOverloads; properties: NpmStaticDeclarationProperties } {
+  const overloads = new Map<string, Map<string, readonly NpmStaticOverloadSignature[]>>();
+  const properties = new Map<string, Map<string, string>>();
   visitNpmStaticDeclarationClosure(services, entryPath, (path, source) => {
-    for (const [className, methods] of parseNpmStaticDeclarationOverloads(
-      services.parse(path, source, "ts"),
-    )) {
+    const sourceFile = services.parse(path, source, "ts");
+    for (const [className, methods] of parseNpmStaticDeclarationOverloads(sourceFile)) {
       const target =
-        classes.get(className) ?? new Map<string, readonly NpmStaticOverloadSignature[]>();
-      classes.set(className, target);
+        overloads.get(className) ?? new Map<string, readonly NpmStaticOverloadSignature[]>();
+      overloads.set(className, target);
       for (const [methodName, signatures] of methods) {
         if (!target.has(methodName)) target.set(methodName, signatures);
       }
     }
-  });
-  return classes;
-}
-
-function npmStaticDeclarationPropertiesOf(
-  services: FrontendServices,
-  entryPath: string,
-): NpmStaticDeclarationProperties {
-  const classes = new Map<string, Map<string, string>>();
-  visitNpmStaticDeclarationClosure(services, entryPath, (path, source) => {
-    for (const [className, properties] of parseNpmStaticDeclarationProperties(
-      services.parse(path, source, "ts"),
-    )) {
-      const target = classes.get(className) ?? new Map<string, string>();
-      classes.set(className, target);
-      for (const [propertyName, type] of properties) {
+    for (const [className, fields] of parseNpmStaticDeclarationProperties(sourceFile)) {
+      const target = properties.get(className) ?? new Map<string, string>();
+      properties.set(className, target);
+      for (const [propertyName, type] of fields) {
         if (!target.has(propertyName)) target.set(propertyName, type);
       }
     }
   });
-  return classes;
+  return { overloads, properties };
 }
 
 /** See LoadResult.startupCrash: Node's exact error message, the IR error
@@ -1096,8 +1086,7 @@ export function loadProgram(
     ) {
       continue;
     }
-    const overloads = npmStaticDeclarationOverloadsOf(services, resolved.typesFile);
-    const properties = npmStaticDeclarationPropertiesOf(services, resolved.typesFile);
+    const { overloads, properties } = npmStaticDeclarationMetadataOf(services, resolved.typesFile);
     const classNames = new Set([...overloads.keys(), ...properties.keys()]);
     if (classNames.size === 0) continue;
     const runtime = resolveBareModule(entryPath, pkg, "js-only");
diff --git a/packages/compiler/src/frontend/services.ts b/packages/compiler/src/frontend/services.ts
index 14b366bfa..a0acb5818 100644
--- a/packages/compiler/src/frontend/services.ts
+++ b/packages/compiler/src/frontend/services.ts
@@ -20,6 +20,12 @@ import * as syntax from "./npm-static-declaration-syntax.js";
 import { normalizeCjsExportsVar } from "./npm-static-cjs-exports-var.js";
 import type { SourceFile } from "./ts7/ast-types.js";
 
+/** Whether the source can contain `word` as a keyword or identifier: it
+ * holds the word itself or a Unicode escape that might spell it. */
+function spells(source: string, word: string): boolean {
+  return source.includes(word) || source.includes("\\u");
+}
+
 /** Evaluate an isolated, self-contained TypeScript callback under a finite
  * budget. Hosts supply execution; shared lowering owns capture checks and
  * verifies the returned value before baking it into the program. */
@@ -150,13 +156,18 @@ export class FrontendServices {
     return normalizeCjsExportsVar(this.parse(path, source, "js"));
   }
   nullableClassFields(path: string, source: string): syntax.NpmStaticOverloadRewrite | null {
+    // Rewrites `null`-initialized fields of class declarations.
+    if (!spells(source, "class") || !spells(source, "null")) return null;
     return syntax.applyNpmStaticNullableClassFields(this.parse(path, source, "js"), source);
   }
   jsDocNamepaths(path: string, source: string): string | null {
-    if (!source.includes("~") && !source.includes("#")) return null;
+    // A namepath segment joined by `#` or `~` (applyNpmStaticJsDocNamepaths).
+    if (!/[$\w][#~][$A-Z_a-z]/.test(source)) return null;
     return syntax.applyNpmStaticJsDocNamepaths(this.parse(path, source, "js"), source);
   }
   findReturnWidening(path: string, source: string): syntax.NpmStaticOverloadRewrite | null {
+    // Widens `find` calls returned by methods of class declarations.
+    if (!spells(source, "class") || !spells(source, "find")) return null;
     return syntax.applyNpmStaticFindReturnWidening(this.parse(path, source, "js"), source);
   }
   declarationProperties(