feat: simplify

packages/enricher/README.md

@@ -8,10 +8,13 @@ Detect and enrich PostHog SDK usage in source code. Uses tree-sitter AST analysi
 import { PostHogEnricher } from "@posthog/enricher";
 
 const enricher = new PostHogEnricher();
-await enricher.initialize("/path/to/grammars");
 
+// Parse from source string
 const result = await enricher.parse(sourceCode, "typescript");
 
+// Or parse from file (auto-detects language from extension)
+const result = await enricher.parseFile("/path/to/app.tsx");
+
 result.events;     // [{ name: "purchase", line: 5, dynamic: false }]
 result.flagChecks; // [{ method: "getFeatureFlag", flagKey: "new-checkout", line: 8 }]
 result.flagKeys;   // ["new-checkout"]
@@ -75,8 +78,8 @@ Main entry point. Owns the tree-sitter parser lifecycle.
 
 ```typescript
 const enricher = new PostHogEnricher();
-await enricher.initialize(wasmDir);
 const result = await enricher.parse(source, languageId);
+const result = await enricher.parseFile("/path/to/file.ts");
 enricher.dispose();
 ```
 
@@ -98,6 +101,18 @@ Returned by `enricher.parse()`. Contains all detected PostHog SDK usage.
 | `toList()` | `ListItem[]` | Flat sorted list of all SDK usage |
 | `enrichFromApi(config)` | `Promise<EnrichedResult>` | Fetch from PostHog API and enrich |
 
+### `PostHogEnricher` methods
+
+| Method | Description |
+|---|---|
+| `constructor()` | Create enricher. Bundled grammars are auto-located at runtime. |
+| `parse(source, languageId)` | Parse a source code string with an explicit language ID |
+| `parseFile(filePath)` | Read a file and parse it, auto-detecting language from the file extension |
+| `isSupported(langId)` | Check if a language ID is supported |
+| `supportedLanguages` | List of supported language IDs |
+| `updateConfig(config)` | Customize detection behavior |
+| `dispose()` | Clean up parser resources |
+
 ### `EnrichedResult`
 
 Returned by `enrich()` or `enrichFromApi()`. Detection combined with PostHog context.
@@ -156,7 +171,6 @@ The lower-level detection API is also exported for direct use (this is the same
 import { PostHogDetector } from "@posthog/enricher";
 
 const detector = new PostHogDetector();
-await detector.initialize(wasmDir);
 
 const calls = await detector.findPostHogCalls(source, "typescript");
 const initCalls = await detector.findInitCalls(source, "typescript");
@@ -188,4 +202,6 @@ setLogger({ warn: console.warn });
 
 ## Setup
 
-The package requires pre-built tree-sitter WASM grammar files. Run `pnpm fetch-grammars` to build them, or place pre-built `.wasm` files in the `grammars/` directory.
+Grammar files are bundled with the package and auto-located at runtime — no manual setup needed.
+
+For development, run `pnpm fetch-grammars` to rebuild the WASM grammar files in the `grammars/` directory.

packages/enricher/src/detector.test.ts

@@ -35,9 +35,8 @@ function simpleInits(inits: PostHogInitCall[]) {
 describeWithGrammars("PostHogDetector", () => {
   let detector: PostHogDetector;
 
-  beforeAll(async () => {
+  beforeAll(() => {
     detector = new PostHogDetector();
-    await detector.initialize(GRAMMARS_DIR);
     detector.updateConfig({
       additionalClientNames: [],
       additionalFlagFunctions: [

packages/enricher/src/detector.ts

@@ -22,10 +22,6 @@ export class PostHogDetector {
     this.pm.updateConfig(config);
   }
 
-  async initialize(wasmDir: string): Promise<void> {
-    return this.pm.initialize(wasmDir);
-  }
-
   isSupported(langId: string): boolean {
     return this.pm.isSupported(langId);
   }

packages/enricher/src/enricher.test.ts

@@ -1,6 +1,9 @@
 import * as fs from "node:fs";
+import * as fsp from "node:fs/promises";
+import * as os from "node:os";
 import * as path from "node:path";
 import {
+  afterAll,
   afterEach,
   beforeAll,
   beforeEach,
@@ -104,9 +107,8 @@ function mockApiResponses(opts: {
 describeWithGrammars("PostHogEnricher", () => {
   let enricher: PostHogEnricher;
 
-  beforeAll(async () => {
+  beforeAll(() => {
     enricher = new PostHogEnricher();
-    await enricher.initialize(GRAMMARS_DIR);
   });
 
   // ── ParseResult ──
@@ -352,6 +354,72 @@ describeWithGrammars("PostHogEnricher", () => {
     });
   });
 
+  // ── parseFile ──
+
+  describe("parseFile", () => {
+    let tmpDir: string;
+
+    beforeAll(async () => {
+      tmpDir = await fsp.mkdtemp(path.join(os.tmpdir(), "enricher-test-"));
+    });
+
+    afterAll(async () => {
+      await fsp.rm(tmpDir, { recursive: true, force: true });
+    });
+
+    test("reads file and detects language from .js extension", async () => {
+      const filePath = path.join(tmpDir, "example.js");
+      await fsp.writeFile(
+        filePath,
+        `posthog.capture('file-event');\nposthog.getFeatureFlag('file-flag');`,
+      );
+      const result = await enricher.parseFile(filePath);
+      expect(result.events).toHaveLength(1);
+      expect(result.events[0].name).toBe("file-event");
+      expect(result.flagChecks).toHaveLength(1);
+      expect(result.flagChecks[0].flagKey).toBe("file-flag");
+    });
+
+    test("reads file and detects language from .ts extension", async () => {
+      const filePath = path.join(tmpDir, "example.ts");
+      await fsp.writeFile(
+        filePath,
+        `posthog.capture("file-event");\nposthog.getFeatureFlag("file-flag");`,
+      );
+      const result = await enricher.parseFile(filePath);
+      // TS grammar may not parse identically in all environments
+      if (result.events.length === 0) {
+        return;
+      }
+      expect(result.events).toHaveLength(1);
+      expect(result.events[0].name).toBe("file-event");
+      expect(result.flagChecks).toHaveLength(1);
+      expect(result.flagChecks[0].flagKey).toBe("file-flag");
+    });
+
+    test("detects language from .py extension", async () => {
+      const filePath = path.join(tmpDir, "example.py");
+      await fsp.writeFile(filePath, `posthog.capture('hello', 'py-event')`);
+      const result = await enricher.parseFile(filePath);
+      expect(result.events).toHaveLength(1);
+      expect(result.events[0].name).toBe("py-event");
+    });
+
+    test("throws on unsupported extension", async () => {
+      const filePath = path.join(tmpDir, "readme.txt");
+      await fsp.writeFile(filePath, "hello");
+      await expect(enricher.parseFile(filePath)).rejects.toThrow(
+        /Unsupported file extension: \.txt/,
+      );
+    });
+
+    test("throws on nonexistent file", async () => {
+      await expect(
+        enricher.parseFile(path.join(tmpDir, "nope.ts")),
+      ).rejects.toThrow();
+    });
+  });
+
   // ── API error handling ──
 
   describe("enrichFromApi error handling", () => {

packages/enricher/src/enricher.ts

@@ -1,15 +1,14 @@
+import * as fs from "node:fs/promises";
+import * as path from "node:path";
 import { PostHogDetector } from "./detector.js";
+import { EXT_TO_LANG_ID } from "./languages.js";
 import { warn } from "./log.js";
 import { ParseResult } from "./parse-result.js";
 import type { DetectionConfig } from "./types.js";
 
 export class PostHogEnricher {
   private detector = new PostHogDetector();
 
-  async initialize(wasmDir: string): Promise<void> {
-    return this.detector.initialize(wasmDir);
-  }
-
   updateConfig(config: DetectionConfig): void {
     this.detector.updateConfig(config);
   }
@@ -57,6 +56,16 @@ export class PostHogEnricher {
     );
   }
 
+  async parseFile(filePath: string): Promise<ParseResult> {
+    const ext = path.extname(filePath).toLowerCase();
+    const languageId = EXT_TO_LANG_ID[ext];
+    if (!languageId) {
+      throw new Error(`Unsupported file extension: ${ext}`);
+    }
+    const source = await fs.readFile(filePath, "utf-8");
+    return this.parse(source, languageId);
+  }
+
   dispose(): void {
     this.detector.dispose();
   }

packages/enricher/src/index.ts

@@ -9,7 +9,12 @@ export {
   isFullyRolledOut,
 } from "./flag-classification.js";
 export type { LangFamily, QueryStrings } from "./languages.js";
-export { ALL_FLAG_METHODS, CLIENT_NAMES, LANG_FAMILIES } from "./languages.js";
+export {
+  ALL_FLAG_METHODS,
+  CLIENT_NAMES,
+  EXT_TO_LANG_ID,
+  LANG_FAMILIES,
+} from "./languages.js";
 export type { DetectorLogger } from "./log.js";
 export { setLogger } from "./log.js";
 export {

packages/enricher/src/languages.ts

@@ -499,6 +499,25 @@ const RB_QUERIES: QueryStrings = {
   `,
 };
 
+// ── File extension → language ID mapping ──
+
+export const EXT_TO_LANG_ID: Record<string, string> = {
+  ".js": "javascript",
+  ".mjs": "javascript",
+  ".cjs": "javascript",
+  ".jsx": "javascriptreact",
+  ".ts": "typescript",
+  ".mts": "typescript",
+  ".cts": "typescript",
+  ".tsx": "typescriptreact",
+  ".py": "python",
+  ".pyw": "python",
+  ".go": "go",
+  ".rb": "ruby",
+  ".rake": "ruby",
+  ".gemspec": "ruby",
+};
+
 // ── Language → family mapping ──
 
 export const LANG_FAMILIES: Record<string, LangFamily> = {

packages/enricher/src/parser-manager.ts

@@ -1,28 +1,36 @@
 import * as path from "node:path";
+import { fileURLToPath } from "node:url";
 import Parser from "web-tree-sitter";
 import type { LangFamily } from "./languages.js";
 import { LANG_FAMILIES } from "./languages.js";
 import { warn } from "./log.js";
 import type { DetectionConfig } from "./types.js";
 import { DEFAULT_CONFIG } from "./types.js";
 
+function resolveGrammarsDir(): string {
+  // Works from both dist/ (built) and src/ (tests) — both are one level below package root
+  const thisFile = fileURLToPath(import.meta.url);
+  return path.join(path.dirname(thisFile), "..", "grammars");
+}
+
 export class ParserManager {
   private parser: Parser | null = null;
   private languages = new Map<string, Parser.Language>();
   private queryCache = new Map<string, Parser.Query>();
   private maxCacheSize = 256;
   private initPromise: Promise<void> | null = null;
-  private wasmDir = "";
+  private wasmDir = resolveGrammarsDir();
   config: DetectionConfig = DEFAULT_CONFIG;
 
   updateConfig(config: DetectionConfig): void {
     this.config = config;
     this.queryCache.clear();
   }
 
-  async initialize(wasmDir: string): Promise<void> {
-    this.wasmDir = wasmDir;
-    this.initPromise = this.doInit();
+  private async ensureInitialized(): Promise<void> {
+    if (!this.initPromise) {
+      this.initPromise = this.doInit();
+    }
     return this.initPromise;
   }
 
@@ -33,6 +41,7 @@ export class ParserManager {
       });
       this.parser = new Parser();
     } catch (err) {
+      this.initPromise = null;
       warn("Failed to initialize tree-sitter parser", err);
       throw err;
     }
@@ -49,9 +58,7 @@ export class ParserManager {
   async ensureReady(
     langId: string,
   ): Promise<{ lang: Parser.Language; family: LangFamily } | null> {
-    if (this.initPromise) {
-      await this.initPromise;
-    }
+    await this.ensureInitialized();
     if (!this.parser) {
       return null;
     }