What causes "Failed to clone ${source}. ${stderr.trim()}" in EveryInc/compound-engineering-plugin?

Read the stderr text embedded in the message — it is git's own diagnosis; fix that first.

EveryInc/compound-engineering-plugin · error · Error

Failed to clone ${source}. ${stderr.trim()}

Error message

Failed to clone ${source}. ${stderr.trim()}

What it means

During by-name installation the CLI shells out to `git clone <source> <tempdir>` via Bun.spawn. If git exits non-zero — bad URL, missing repo, no network, auth failure — the command surfaces git's stderr verbatim in this error so the underlying cause is visible.

Source

Thrown at src/commands/install.ts:341

function resolveGitHubSource(): string {
  const override = process.env.COMPOUND_PLUGIN_GITHUB_SOURCE
  if (override && override.trim()) return override.trim()
  return "https://github.com/EveryInc/compound-engineering-plugin"
}

async function cloneGitHubRepo(source: string, destination: string, branch?: string): Promise<void> {
  const args = ["git", "clone", "--depth", "1"]
  if (branch) args.push("--branch", branch)
  args.push(source, destination)
  const proc = Bun.spawn(args, {
    stdout: "pipe",
    stderr: "pipe",
  })
  const exitCode = await proc.exited
  const stderr = await new Response(proc.stderr).text()
  if (exitCode !== 0) {
    throw new Error(`Failed to clone ${source}. ${stderr.trim()}`)
  }
}

View on GitHub (pinned to c9c10f8c75)

Solutions

Read the stderr text embedded in the message — it is git's own diagnosis; fix that first.
Verify the source URL: `git ls-remote <source>` (or check COMPOUND_PLUGIN_GITHUB_SOURCE if set).
Check network/proxy connectivity to github.com; retry when offline.
For private repos, configure credentials (gh auth login, ssh keys, or token-based HTTPS).
Fall back to a local path: `install ./path/to/cloned/plugin`.

Example fix

// before (message tail: 'Repository not found')
COMPOUND_PLUGIN_GITHUB_SOURCE=git@github.com:me/wrong-repo.git install compound-engineering
// after
unset COMPOUND_PLUGIN_GITHUB_SOURCE  # use the default marketplace source
install compound-engineering

Defensive patterns

Strategy: retry

Validate before calling

// Pre-flight: check the remote is reachable before install
const { exitCode } = Bun.spawnSync(["git", "ls-remote", source, "HEAD"])
if (exitCode !== 0) throw new Error(`Cannot reach ${source}; fix network/auth first`)

Try / catch

try {
  await install(pluginName)
} catch (e) {
  if (e instanceof Error && e.message.startsWith("Failed to clone")) {
    // e.message contains git's stderr; retry with backoff on transient network errors
    await sleep(2000)
    await install(pluginName)
  } else throw e
}

Prevention

Run `git ls-remote <source>` before scripted installs to catch auth/network issues early.
Configure credentials once (gh auth login / ssh keys) for private sources.
Avoid typos in COMPOUND_PLUGIN_GITHUB_SOURCE; test it with ls-remote.
Retry transient failures instead of reinstalling from a changed source.

When it happens

Trigger: Calling `install <plugin-name>` when the git clone of the source repo fails: repo does not exist or is private (auth needed), no network/DNS failure, COMPOUND_PLUGIN_GITHUB_SOURCE set to an invalid URL, git not on PATH produces its own error, or proxy/firewall blocks github.com.

Common situations: Offline or corporate-proxy environment; SSH vs HTTPS mismatch for private repos; expired credentials/token; COMPOUND_PLUGIN_GITHUB_SOURCE typo; rate limiting or VPN issues.

Related errors

AI-assisted analysis of EveryInc/compound-engineering-plugin@c9c10f8c75 (2026-08-31). Data as JSON: /api/errors/8d6d5a606dd0a66e. Report an issue: GitHub.