## Context

I attempted to run **OpenCode** (`@opencode-ai/server`) inside Celld as a stateful coding agent running in a Durable Object with SQLite persistence:

```typescript import { DurableObject } from "cloudflare:workers"; import { OpenCodeWorkerd } from "@opencode-ai/server";

export class OpenCodeDO extends DurableObject { async fetch(req: Request) { // 1. Initialize OpenCode engine const opencode = await OpenCodeWorkerd.create({ storage: this.ctx.storage, config: { defaultModel: "google/gemini-2.5-flash" }, });

// 2. Create session & run prompt const session = await opencode.session.create(); await opencode.session.prompt({ sessionID: session.id, text: "hello world", });

return new Response("OK"); } } ```

When building and deploying this on Celld (v0.3.0), the code fails across four sequential phases due to Node compatibility gaps.

## Compatiblity Gaps ### Missing CJS require

``` ReferenceError: require is not defined at node_modules/@opencode-ai/server/... ```

### `node:os`

``` TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received an instance of NodeStub at path.join (node:path) ```

### `node:fs`

``` FiberFailure: (FiberSet) Defect: TypeError: stats.isDirectory is not a function at SessionRunner.resolveWorkspaceDirectory ```

### `node:child_process`

``` TypeError: Cannot read properties of undefined (reading 'on') at Shell.create (node_modules/@opencode-ai/server/...) ```

## Minimal, reproducible example

```js // repro-worker.js import os from "node:os"; import path from "node:path"; import fs from "node:fs"; import { spawn } from "node:child_process";

export default { async fetch(req) { const results = [];

// 1. node:os string return contract try { const home = os.homedir(); // Expectation: home is a string (e.g. "/root") // Reality in Celld: home is a NodeStub Proxy object path.join(home, ".config"); results.push("✓ os.homedir() contract: OK"); } catch (err) { results.push(`✗ os.homedir() contract failed: ${err.message}`); }

// 2. node:fs stat / realpathSync interface try { const real = fs.realpathSync("/workspace"); if (typeof real !== "string") { throw new TypeError(`Expected string, got ${typeof real}`); } fs.stat(real, (err, stats) => { if (!stats || typeof stats.isDirectory !== "function") { throw new TypeError("stats.isDirectory is not a function"); } }); results.push("✓ node:fs stat/realpath contract: OK"); } catch (err) { results.push(`✗ node:fs contract failed: ${err.message}`); }

// 3. node:module / dynamic CJS require try { if (typeof require === "undefined") { throw new ReferenceError("require is not defined"); } results.push("✓ require exists: OK"); } catch (err) { results.push(`✗ require failed: ${err.message}`); }

// 4. node:child_process spawn interface try { const proc = spawn("bash", ["-c", "echo 1"]); if (!proc || !proc.stdout || typeof proc.stdout.on !== "function") { throw new TypeError("proc.stdout.on is not a function"); } results.push("✓ child_process.spawn contract: OK"); } catch (err) { results.push(`✗ child_process.spawn failed: ${err.message}`); }

return new Response(results.join("\n"), { headers: { "content-type": "text/plain" }, }); }, }; ```