Watchman is a file watching service developed by Facebook, and it's used by many projects (such as Sorbet's LSP) to watch files for changes, triggering project rebuilds whenever a change is detected.
Instead of figuring out how to build watchman from source - or waiting for long compilation times when building your Dockerfiles - you can use the "Multi-stage Dockerfile" feature to copy the watchman executable directly from our image!
Remember that the image lives on GitHub Container Registry, not Docker Hub, so use
ghcr.io/dockwa/watchman:<TAG>!
# Start from whatever image you are using - this is a node app example:
FROM node:8-alpine
# Install the packages required for watchman to work properly:
RUN apk add --no-cache libcrypto1.0 libgcc libstdc++
# Copy the watchman executable binary directly from our image:
COPY --from=ghcr.io/dockwa/watchman:4.9.0-alpine-3.15 /usr/local/bin/watchman* /usr/local/bin/
# Create the watchman STATEDIR directory:
RUN mkdir -p /usr/local/var/run/watchman \
&& touch /usr/local/var/run/watchman/.not-empty
# (Optional) Copy the compiled watchman documentation:
COPY --from=ghcr.io/dockwa/watchman:4.9.0-alpine-3.15 /usr/local/share/doc/watchman* /usr/local/share/doc/
# Continue with the rest of your Dockerfile...
Thanks to IcaliaLabs for the original implementation; this repo is mostly a version bump and GHCR packaging layer with a slightly different tagging scheme.