In which language Go is implemented?

Go, also known as Golang, was primarily implemented in C. It was designed by Robert Griesemer, Rob Pike, and Ken Thompson from Google in 2007 and publicly released in 2009. Their goal was to create a language with static type safety and efficient compilation while maintaining the ease of use characteristic of dynamic languages like Python. The Go compiler "gc" was initially written in C to leverage the maturity and widespread support of C. As the language evolved, the Go compiler was gradually rewritten in Go itself. This process, known as bootstrapping, means the Go compiler could eventually compile itself, which is an important step in the development of many modern programming languages. Since version 1.5 in 2015, the Go compiler has been completely written in Go. Rewriting the compiler in Go not only enhanced trust and reliance in the Go language itself but also facilitated understanding and optimization of its performance and features. This bootstrapping process also serves as a key indicator of the maturity of the Go language.