Installing and deploying

From source

The server is C++17 on Drogon, with SQLite for the default storage.

brew install drogon sqlite     # or: apt install libdrogon-dev libsqlite3-dev, vcpkg install drogon sqlite3, …
cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build
./build/openvireo-sync-server  # http://127.0.0.1:8787, data in ./data

Postgres and S3 support (see Storage) needs Drogon built with PostgreSQL (-DBUILD_POSTGRESQL=ON), which Homebrew’s and most distributions’ packages are not. CMake turns it on when it finds such a Drogon; -DSYNC_SERVER_WITH_CLOUD=ON makes it required. The Docker image always has it.

cmake --install build installs the single binary, openvireo-sync-server. It has no other files.

Docker

Released images for linux/amd64 and linux/arm64 are on GHCR:

docker run -d --name openvireo-sync -p 127.0.0.1:8787:8787 -v openvireo-sync:/data \
  -e SYNC_BEHIND_PROXY=1 ghcr.io/openvireo/openvireo-sync-server:1
docker exec openvireo-sync openvireo-sync-server users add alice laptop

Tags: :latest, :1, :1.2, :1.2.3 (a pre-release such as 1.3.0-rc.1 gets only its own tag). The image runs as an unprivileged user (uid 10001), listens on 0.0.0.0:8787 and keeps the data directory in /data; a bind-mounted directory must be writable by that uid. Publish the port on 127.0.0.1 only and put HTTPS in front of it (see below); SYNC_BEHIND_PROXY=1 says you did.

To build from this repository instead:

docker compose up -d --build                                  # data directory in a volume, on 127.0.0.1:8787
docker compose run --rm sync-server users add alice laptop

SYNC_HOST_PORT=18787 publishes on another port.

compose.cloud.yaml runs the stateless setup locally: Postgres, an S3 gateway standing in for Spaces, two server instances and nginx in front of them:

docker compose -f compose.cloud.yaml up -d --build
docker compose -f compose.cloud.yaml run --rm migrate users add alice laptop
docker compose -f compose.cloud.yaml run --rm --build test    # the API tests against Postgres and the bucket

DigitalOcean App Platform

.do/app.yaml deploys two instances from the Dockerfile with a managed Postgres database and a Spaces bucket. Create the bucket and a Spaces access key first, fill in the placeholders, then:

doctl apps create --spec .do/app.yaml

App Platform terminates HTTPS. Add users from the app’s console (openvireo-sync-server users add alice laptop) or from any machine with the same SYNC_* settings.

HTTPS and reverse proxies

The access token travels in the Authorization header, so use HTTPS for anything other than localhost. Keep the server on 127.0.0.1 and put a TLS-terminating reverse proxy (Caddy, nginx, …) in front of it. For example, with Caddy:

sync.example.com {
    reverse_proxy 127.0.0.1:8787
}

With nginx, turn off buffering for the events stream and allow long-lived requests:

location / {
    proxy_pass http://127.0.0.1:8787;
    proxy_http_version 1.1;
    proxy_set_header Connection "";
    proxy_buffering off;          # the server also sends X-Accel-Buffering: no
    proxy_read_timeout 1h;        # events streams stay open; the server pings every 25 seconds
    client_max_body_size 50m;     # at least SYNC_MAX_DB_BYTES
}

Things to keep in mind behind a proxy:

• The server warns when it listens on a non-loopback address; SYNC_BEHIND_PROXY=1 silences that once TLS is terminated in front of it.
• OpenVireo does not follow redirects, so the token is never forwarded to another host. Enter the final https:// URL.
• The pairing rate limit is per client address, and behind a proxy every client has the proxy’s address (see Pairing).
• If web apps call the server (see CORS), let the proxy pass OPTIONS requests through rather than answering them itself.

The Sync Server docs cover OpenVireo Sync Server, develop (0d4f752), last updated 26 October 2026. Found a mistake? Edit this page on GitHub.