The go run and go build Commands

Using go run

'go run' compiles your code to a temporary location and runs it in a single command, then discards the binary. It's the fastest feedback loop for development because you never have to think about the intermediate executable file.

Example: Using go run

go run main.go

Using go build

'go build' compiles your program and writes a real executable file to the current directory, named after the module or the source file by default. This binary is a complete, self-contained program -- it embeds the Go runtime, so the machine running it does not need Go installed.

Note: On Windows the produced file automatically gets a .exe extension.

Example: Using go build

go build main.go

Naming the Output with -o

The -o flag lets you choose exactly where the compiled binary goes and what it's named, which is useful in build scripts and CI pipelines where a predictable filename matters.

Example: Naming the Output with -o

go build -o myapp main.go

Running the Compiled Binary

Once built, you execute the binary directly like any other program on your system. This two-step build-then-run workflow is what you'd use for anything meant to be deployed or distributed, as opposed to 'go run' which is meant purely for local iteration.

Note: Prefixing with ./ tells the shell to run the file from the current directory rather than searching PATH.

Example: Running the Compiled Binary

./myapp