Starlark, a configuration language for the Bazel build tool, has a tree-walking interpreter implemented in pure Go at google/starlark-go.

It seems like the canonical implementation of Starlark is the Java implementation in the Bazel source tree, but the Go version is used "in production" in web playgrounds, debuggers, and so on.

starlark-go is notable because it's one of a vanishingly small number of production language implementations that are tree-walking interpreters rather than bytecode VMs. The implementation guide says:

The evaluator uses a simple recursive tree walk, returning a value or an error for each expression. We have experimented with just-in-time compilation of syntax trees to bytecode, but two limitations in the current Go compiler prevent this strategy from outperforming the tree-walking evaluator.

The details of why exactly that's the case is interesting, and documented further in the link, but seem inherent to Go's current compiler design and philosophy. It also supports Oak's current (tree-walking) evaluator design, which is nice.