build: add docker support for local testing

this should build and start a local jekyll+github server to test changes
locally (only tested on linux)

% docker compose build --pull
% docker compose up -d

hopefully the Gemfile doesn't muck with the GH Pages deployment or we'll
need to put it somewhere else e.g., `.deploy/`

.gitignore

@@ -64,3 +64,27 @@ $RECYCLE.BIN/
 
 # Things specific to this directory.
 # .............................................................................
+
+# Jekyll / Ruby things
+### Jekyll ###
+_site/
+.sass-cache/
+.jekyll-cache/
+.jekyll-metadata
+# Ignore folders generated by Bundler
+.bundle/
+vendor/
+
+### Ruby ###
+*.gem
+*.rbc
+Gemfile.lock
+/.config
+/coverage/
+/InstalledFiles
+/pkg/
+/spec/reports/
+/spec/examples.txt
+/test/tmp/
+/test/version_tmp/
+/tmp/

Dockerfile

@@ -0,0 +1,33 @@
+FROM ruby:3-bookworm
+
+ENV SETUPDIR=/setup
+WORKDIR ${SETUPDIR}
+ARG GEMFILE_DIR=.
+COPY $GEMFILE_DIR/Gemfile* $GEMFILE_DIR/packages* ./
+
+# Install build dependencies
+RUN set -eux; \
+    apt update && \
+    apt upgrade -y
+
+# Install Bundler
+RUN set -eux; gem install bundler
+
+# Install gems from `Gemfile` via Bundler
+RUN set -eux; bundler install
+
+# Remove build dependencies
+RUN set -eux; apt clean
+
+# Clean up
+WORKDIR /srv/jekyll
+RUN set -eux; \
+    rm -rf \
+        ${SETUPDIR} \
+        /usr/gem/cache \
+        /root/.bundle/cache \
+    ;
+
+EXPOSE 4000
+ENTRYPOINT ["bundle", "exec", "jekyll"]
+CMD ["--version"]

Gemfile

@@ -0,0 +1,3 @@
+source "https://rubygems.org"
+
+gem "github-pages", "~> 232", group: :jekyll_plugins

_config.yml

@@ -1,5 +1,6 @@
 remote_theme: pages-themes/[email protected]
 title: SciCodes Collaboration Workshop
 description: A Sloan Foundation-funded workshop for editors & maintainers of academic discipline & institutional software registries & repositories
+repository: SciCodes/workshop-2025
 plugins:
   - jekyll-remote-theme

docker-compose.yml

@@ -0,0 +1,10 @@
+services:
+  site:
+    build: .
+    image: scicodes-2025-site:latest
+    entrypoint: ["bundle", "exec", "jekyll", "serve", "--host=0.0.0.0", "--incremental"]
+    ports: 
+      - 4000:4000
+    volumes:
+      - .:/srv/jekyll:Z
+      - ./vendor/bundle:/usr/local/bundle:Z