Why is it recommended to use `go build` instead of `go run` when running a Go app in production?

Question

I have a Dockerfile that I used to compile the Go app using go build . I researched and indeed go build is recommended for production.

However I cannot find a proper answer as to why.

I understand go run creates a temporary file that and that cleans up on app termination. But if I am using Docker, why is it bad to use go run instead of go build ?

Answer 1

Several reasons:

• A Go application does not require the Go toolchain, just as a C application doesn't require gcc . If you use go build , you can just deploy a binary; if you use go run , you have to install the toolchain.
• go run compiles the application unnecessarily every time it's run, increasing startup times.
• go run forks the application to a new process, making process management unnecessarily complicated by obscuring PIDs and exit statuses.
• go run has the potential to unexpectedly absorb code changes when you're only intending to run an application. Using go build only when you want a fresh binary allows you to re-run the same, consistent binary every time with no unexpected changes.