Go (a.k.a., Golang) is a programming language first developed at Google. It is a statically-typed language with syntax loosely derived from C, but with additional features such as garbage collection, type safety, some dynamic-typing capabilities, additional built-in types (e.g., variable-length arrays and key-value maps), and a large standard library.
Note: /go is world-writable to allow flexibility in the user which runs the container (for example, in a container started with --user 1000:1000, running go get github.com/example/... into the default $GOPATH will succeed). While the 777 directory would be insecure on a regular host setup, there are not typically other processes or users inside the container, so this is equivalent to 700 for Docker usage, but allowing for --user flexibility.