Deploy a Go app

We detect Go from go.mod, download modules, and build a binary named out:

• A main.go at the repo root is built with go build -o out.
• With no root main.go, the package under cmd/<name> is built. If you have several, set the Build command, for example go build -o out ./cmd/api.
• CGO_ENABLED=0 is set, so the binary is static. Packages that need cgo (such as mattn/go-sqlite3) won't build; use a pure-Go alternative like modernc.org/sqlite, or set CGO_ENABLED=1 as an env var.

package main

import (
	"net/http"
	"os"
)

func main() {
	mux := http.NewServeMux()
	mux.HandleFunc("GET /healthz", func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("ok"))
	})
	http.ListenAndServe(":"+os.Getenv("PORT"), mux)
}

If go.mod asks for a newer Go than the build image has, Go downloads that toolchain during the build. This needs the full version in go.mod (go 1.25.0, not go 1.25), which is what go mod init and go get go@latest write.

Files your binary reads at runtime (templates, static assets) are copied with the repo, but //go:embed keeps everything in the binary and avoids path surprises.

Every deploy requests your health check path (/ by default) and only goes live once it returns a 2xx or 3xx status. The platform keeps checking it after that. If / returns 404 or needs a login, add a route like /healthz that returns 200 and set it as the Health Check Path in Settings. Otherwise the deploy fails and the previous version keeps serving.

Add a Postgres addon and DATABASE_URL is injected automatically. pgx accepts it as-is:

pool, err := pgxpool.New(ctx, os.Getenv("DATABASE_URL"))

Run migrations (goose, golang-migrate, Atlas) when the binary starts, or in front of it in the Start command.

On each deploy, the old container is stopped once the new one is healthy. Catch SIGTERM and call Shutdown so requests in flight finish:

srv := &http.Server{Addr: ":" + os.Getenv("PORT"), Handler: mux}
go srv.ListenAndServe()

ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGTERM, os.Interrupt)
defer stop()
<-ctx.Done()
srv.Shutdown(context.Background())

A Go program with no HTTP server (a queue consumer, a Telegram bot) runs as a Background Worker: set the service type in Settings. It skips the HTTP health check, and the old instance is stopped before the new one starts, so two copies never poll at once.

1. Sign in with GitHub and install the EthioDeploy app on the repo.
2. Click “New Project” and pick the repo.
3. Watch the build in the dashboard. When the health check passes, your app is live at <project-slug>.ethiodeploy.com. Every push to the default branch redeploys, and the old version keeps serving until the new one is healthy.