Node "Cannot find module 'node:crypto'" - Fix node: Builtins on Old Node in CI

By Kaveh Alemi·Latchkey

The node: import prefix (e.g. node:crypto, node:fs) is only recognized by newer Node versions. On an older runner Node, the resolver treats node:crypto as a missing package and throws.

What this error means

Code or a dependency importing node:crypto (or node:fs, node:path, …) fails with Cannot find module 'node:crypto' in CI, while it works locally on a newer Node. The tell is the node: prefix and an older runner Node.

Node output

Error: Cannot find module 'node:crypto'
Require stack:
- /app/dist/index.js
    at Function._resolveFilename (node:internal/modules/cjs/loader)
    ... code: 'MODULE_NOT_FOUND'

Diagnose it: what is different about the runner?

A build that passes locally and fails on a runner differs in a small number of predictable ways. Check those before changing build configuration, because the build config is usually not the thing that changed.

.github/workflows/ci.yml

- run: |
    node --version && npm --version
    echo "NODE_ENV=$NODE_ENV  CI=$CI"
    nproc && free -h && df -h /
    ls -la node_modules/.bin | head

Common causes

Runner Node is too old for the node: scheme

The node: builtin prefix is supported from Node 14.18/16+. On an older runner Node, node:crypto is unresolved and throws MODULE_NOT_FOUND.

A dependency upgraded to node: imports

A bumped dependency now uses node:-prefixed builtins; if CI still runs an older Node, that dependency cannot load.

How to fix it

Upgrade CI Node to a supported version

Run a Node version that recognizes the node: builtin scheme.

Workflow

- uses: actions/setup-node@v4
  with:
    node-version: 20
- run: node --version

Align Node with your dependencies

Set engines.node and .nvmrc to a version supporting node: builtins.
Upgrade Node in CI when a dependency adopts node: imports.
Keep local, CI, and prod Node versions in sync.

The three that account for most of them

Case sensitivity. Linux runners are case sensitive, macOS is not. An import with the wrong case resolves locally and fails in CI.
Out of memory. Exit code 137 is a SIGKILL from the kernel, not a build error. Raise --max-old-space-size or use a larger runner.
devDependencies pruned. NODE_ENV=production makes npm ci skip devDependencies, so the build tool itself goes missing. Set it after install, not before.

How to prevent it

Run a current Node LTS in CI.
Declare engines.node and use .nvmrc/setup-node.
Bump Node when dependencies require newer builtins.

Frequently asked questions

What causes Node "Cannot find module 'node:crypto'"?

There are 2 common causes: runner node is too old for the node: scheme and a dependency upgraded to node: imports. The node: builtin prefix is supported from Node 14.18/16+.

How do I fix Node "Cannot find module 'node:crypto'"?

There are 2 fixes depending on which cause you have: upgrade ci node to a supported version and align node with your dependencies. Work through them in order, since the first is the most common.

What does Node "Cannot find module 'node:crypto'" actually mean?

Code or a dependency importing node:crypto (or node:fs, node:path, …) fails with Cannot find module 'node:crypto' in CI, while it works locally on a newer Node.

How do I stop Node "Cannot find module 'node:crypto'" happening again?

Run a current Node LTS in CI. The prevention section lists 3 changes that keep it from recurring.