# Node ERR_UNSUPPORTED_DIR_IMPORT in CI - Import a File, Not a Directory

> Fix the Node.js ERR_UNSUPPORTED_DIR_IMPORT error in CI by importing an explicit file path instead of a directory under native ESM resolution.

Source: https://latchkey.dev/learn/node-js/node-err-unsupported-dir-import-runtime-in-ci  
Updated: 2026-06-26

ERR_UNSUPPORTED_DIR_IMPORT means native ESM was asked to import a directory. Unlike CommonJS, ESM does not auto-resolve a folder to its index file.

## Diagnose it: the shell in CI is not your shell

Package scripts run under a different shell, a different PATH, and a non-interactive environment on a runner. Most scripts that fail only in CI are relying on something the login shell gave them locally: a tool on PATH, an environment variable from a dotfile, or a TTY.

```Terminal
# what the script can actually see
npm run env | grep -E "^(PATH|NODE_ENV|CI)=" 

# is the binary on PATH for the script, not just for you?
npm exec -- which <tool> || echo "not resolvable from npm scripts"

# run the exact script with tracing
sh -x -c "$(node -p "require('./package.json').scripts.build")"
```

> A tool installed globally on your machine but only a devDependency in the repo works locally and fails in CI. Call it through `npm exec` or a `node_modules/.bin` path rather than assuming it is on PATH.

## Make failures fail the job

A multi-command script can report success while a middle command failed, which produces the worst kind of CI result: a green build that shipped something broken.

```.github/workflows/ci.yml
# pipefail is NOT set by default in every runner shell
- name: Build
  shell: bash
  run: |
    set -euo pipefail
    npm run build | tee build.log
```

> Without `pipefail`, the exit status of a pipeline is the status of the LAST command, so `failing-command | tee log` reports success. Piping build output to a log file is exactly where this bites.

## FAQ

### What causes Node ERR_UNSUPPORTED_DIR_IMPORT in CI?

There are 2 common causes: importing a folder under native esm and a typescript directory import not rewritten on emit. ESM does not append /index.js to a directory specifier, so a directory import fails.

### How do I fix Node ERR_UNSUPPORTED_DIR_IMPORT in CI?

Import the explicit index file. Change the directory import to point at the concrete file.

### What does Node ERR_UNSUPPORTED_DIR_IMPORT in CI actually mean?

A program run as ESM throws Error [ERR_UNSUPPORTED_DIR_IMPORT] for an import that points at a directory rather than a concrete file.

### How do I stop Node ERR_UNSUPPORTED_DIR_IMPORT in CI happening again?

Write explicit file paths with extensions in ESM source, avoid directory imports, and configure the compiler to emit resolvable specifiers.

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Latchkey runs CI/CD that repairs its own failures. Agent entry points: https://latchkey.dev/agent.txt, https://latchkey.dev/openapi.json, https://latchkey.dev/llms.txt