oven-sh/bun · error · Error

not implemented right

Error message

not implemented right

What it means

Generic write/IO failure in install-related code. Notably every `std::io::Error` inside the install crate converts to this variant (From impl at src/install/error.rs:420-424), and commands that emit JSON map write errors to it (e.g. src/runtime/cli/pm_pkg_command.rs:229). Printing a lockfile treats WriteFailed/BrokenPipe as benign (src/install/lockfile.rs:1646).

Source

Thrown at bench/emitter/realworld_stream.mjs:58

      recived.push(req);
    });

    stream.on("end", ev => {
      ev.preventDefault();
    });

    // simulate a stream
    stream.emit("start", { status: 200 });
    for (let chunk of chunks) {
      stream.emit("data", chunk);
    }
    stream.emit("end", {
      preventDefault() {
        id++;
      },
    });

    if (id !== 1) throw new Error("not implemented right");
    if (recived.length !== 1024) throw new Error("not implemented right");
  });
});

await run();

View on GitHub (pinned to 8c5296ac45)

Solutions

1. Check free space and write permissions on the project dir and cache dir (`df -h`, `ls -ld . ~/.bun/install/cache`)
2. Free space / fix ownership, then rerun the command
3. If it only happens when piping to `head`, note the lockfile printer already swallows it - otherwise avoid closing the pipe early
4. In Docker/CI, ensure the workspace volume is writable by the bun user

Example fix

# before
$ sudo bun install   # node_modules owned by root
$ bun install         # WriteFailed for later runs

# after
$ sudo chown -R $(id -u):$(id -g) node_modules && bun install

import { statfsSync, accessSync, constants } from "node:fs";
function canInstall(dir = process.cwd()) {
  accessSync(dir, constants.W_OK);
  const { bavail, bsize } = statfsSync(dir);
  return bavail * bsize > 500 * 1024 * 1024; // require >=500MB free
}

When it happens

Trigger: Disk full or quota exceeded while writing node_modules, bun.lock, or cache files; permission denied on the target directory; stdout/stderr closed early by a consumer during a command that writes output.

Common situations: Full CI disks or container size limits; read-only workspace mounts; project or cache dir owned by another user (root via sudo bun); piping command output to `head`.

Related errors

• AccessDenied
• blob.text() failed
• Your package manager doesn't seem to support bun. To use bun
• Failed to write file ${file}
• FileNotFound

AI-assisted analysis of oven-sh/bun@8c5296ac45 (2026-08-16). Data as JSON: /api/errors/cf3562f91d0a94ac. Report an issue: GitHub.