@entwico/nft-docker

CLI for shrinking Node.js Docker images. Traces what your entrypoint(s) actually import at runtime via @vercel/nft and deletes the rest of node_modules/.

Designed to be run via npx inside a Dockerfile — not a project dependency.

Commands

install

Full Docker-build cycle: install (with hoisted linker for pnpm) → prune.

npx @entwico/nft-docker install -e ./dist/server/entry.mjs

prune

Trace + delete pass on an existing node_modules/. For pnpm projects, the install that produced node_modules/ must have used --node-linker=hoisted — symlinked layouts cannot be pruned reliably.

npx @entwico/nft-docker prune -e ./dist/server/entry.mjs

Flags

Flag	Description
-e <path>, --entrypoint <path>	Entry to trace from. Repeat for multiple entrypoints (e.g. server + worker).
-p <glob>, --preserve <glob>	Extra files to keep regardless of trace output (fontsource woffs, locale JSONs, anything referenced via non-literal import.meta.resolve() or require(varName)). Repeatable. Patterns matching nothing throw.
-r, --rewrite	(Experimental) Rebundle entries with rolldown before pruning. Much smaller images and faster cold starts.=
--no-minify	(--rewrite only) Disable minification of the rewritten bundle. Default: on.
--no-sourcemap	(--rewrite only) Skip emitting .mjs.map files. Default: on. With sourcemaps, run with node --enable-source-maps for symbolicated stack traces.
-v, --verbose	Verbose logs

Dockerfile examples

Build in CI, prune in Docker

FROM node:24-alpine

RUN corepack enable pnpm
WORKDIR /srv
RUN addgroup -S app && adduser -S app -G app && apk add --no-cache tini

COPY package.json pnpm-lock.yaml /srv/
COPY dist/ /srv/dist/

RUN npx @entwico/nft-docker install -e ./dist/server/entry.mjs

USER app
ENTRYPOINT ["tini", "--", "node", "./dist/server/entry.mjs"]

Install, build, and prune inside Docker

FROM node:24-alpine AS builder

RUN corepack enable pnpm
WORKDIR /srv

COPY package.json pnpm-lock.yaml /srv/
RUN pnpm install --frozen-lockfile --node-linker=hoisted

COPY . /srv/
RUN pnpm run build

RUN npx @entwico/nft-docker prune -e ./dist/server/entry.mjs

# --- final image ---
FROM node:24-alpine
WORKDIR /srv
RUN addgroup -S app && adduser -S app -G app && apk add --no-cache tini

COPY --from=builder --chown=app:app /srv/node_modules /srv/node_modules/
COPY --from=builder --chown=app:app /srv/dist /srv/dist/

USER app
ENTRYPOINT ["tini", "--", "node", "./dist/server/entry.mjs"]

For npm projects, swap the lockfile and drop the corepack line.

With --preserve for assets

npx @entwico/nft-docker install \
  -e ./dist/server/main.mjs \
  -p './node_modules/@fontsource/poppins/**' \
  -p './node_modules/some-i18n-pack/locales/*.json'

With --rewrite for aggressive bundling

npx @entwico/nft-docker prune --rewrite \
  -e ./dist/server/entry.mjs \
  -e ./src/instrument.mjs

# run the resulting bundle with sourcemaps enabled:
node --enable-source-maps ./dist/server/entry.mjs

License

MIT