We run a version control server for testing at

Machine initialization

The machine should just run. You should not need these instructions very often. In particular you do not need them just to make a change to vcweb. Skip ahead to the next section.

The VM runs in the builder project “symbolic-datum-552” in zone us-central1-a, where it has a reserved static IP address named vcs-test.

To destroy the current VM (if any) and rebuild a fresh one in its place, run:

./ && ./ && ./

You should not need to do this unless you have changed and want to test it.

To delete the VM's current systemd configuration for vcweb and upload the configuration from the local directory (specifically, vcweb.service and vcweb*.socket), run:

./ && ./

You should not need to do this unless you have changed the systemd configuration files.


The Go program that runs the actual server is in the subdirectory vcweb. For local development:

go build -o vcweb.exe ./vcweb && ./vcweb.exe

It maintains files in /tmp/vcweb and serves localhost:8088.

Once you are happy with local testing, deploy to the VM by running ./


The server can serve Bazaar, Fossil, Git, Mercurial, and Subversion repositories. The root of each repository is, where VCS is the version control system's command name (bzr for Bazaar, and so on), and REPONAME is the repository name.

To serve a particular repository, the server downloads gs://vcs-test/VCS/ from Google Cloud Storage and unzips it into an empty directory. The result should be a valid repository directory for the given version control system. If the needed format of the zip file is unclear, download and inspect gs://vcs-test/VCS/ from

Google Cloud Storage imposes a default Cache-Control policy of 3600 seconds for publicly-readable objects; for instructions to disable caching per object, see gsutil setmeta. vcweb itself may serve stale data for up to five minutes after a zip file is updated. To force a rescan of Google Cloud Storage, fetch

Static files

The URL space is served by static files, fetched from gs://vcs-test/go/ The main use for static files is to write redirect HTML. See gs://vcs-test/go/ for examples. Note that because the server uses http.DetectContentType to deduce the content type from file data, it is not necessary to name HTML files with a .html suffix.


The server fetches an HTTPS certificate on demand from Let's Encrypt, using It caches the certificates in gs://vcs-test-autocert using