embedded-scripting-languages VS starlark-go

Hopefully the linked README provides a general overview (I know I need to write some more documentation!), but Steel is an implementation of the scheme programming language (not entirely compliant yet, but aiming for R5RS and R7RS compliance). It can be used as a standalone language via the interpreter/repl (like Python or Racket), or it can be embedded inside applications, like Lua. There are hundreds (thousands, probably) of embeddable languages, each with their own flavor - see a list compiled here for example https://github.com/dbohdan/embedded-scripting-languages

Use cases are generally for either configuration, scripting, or plugins - so scripting in games, or adding extensions to your text editor without having to use FFI or RPC + serializing a bunch of data. The advantage it has over using dynamic libraries (in general) is it runs in the same process, and can access the internal data structures directly without a lot of ceremony involved. The downside is typically is not as fast as native code unless a JIT is involved.

Javascript is an example of an embedded scripting, where the browser is the host application.

> There is a huge opportunity, IMO, for more players here.

There are quite a few embeddable scripting languages [1]. I think these days it's less common to embed a language mostly because there are good high-level languages that applications can be predominantly written in.

[1] https://github.com/dbohdan/embedded-scripting-languages

I'm not a huge fan of Lua but I think it is at least way more popular and better on every measure than TCL. There are plenty of other better less well-known options too: Rhai, Wren, AngelScript, Starlark (for some use cases), etc. There's a good list here.

or perhaps use one of this list (depending on who's writing the configuration): https://github.com/dbohdan/embedded-scripting-languages

https://github.com/dbohdan/embedded-scripting-languages (coincidentally, from a user whose name I recognize from the Tcl wiki)

Starlark in go https://github.com/google/starlark-go is a great way to combine the best of both, the ease of use of Python and the simplicity of go.

I have been building a platform for deploying internal web applications using this approach https://github.com/claceio/clace. Use Starlark to configure the application, the platform itself is built in go.

The big unknown is your task definition: what does user-defined logic look like? If you're expecting go code, that's gonna need some cleverness because of the compiled nature of it. There's a node runtime implemented in go if you want to provide sandboxed javascript (check the source of k6.io, it's the main one I know that uses it). If you want to provide building blocks and let them compose them, starlark might be a good choice.

Another one of those (with broader language support) is the Starlark language, which has a Go implementation: https://github.com/google/starlark-go

Every config format gets as complex to be touring complete in the end. We had similar problems and eventually got rid of that complexity and switched to starlark (the bazel config language), was a huge benefit for the tools. https://github.com/google/starlark-go "Starlark is a dialect of Python intended for use as a configuration language. Like Python, it is an untyped dynamic language with high-level data types, first-class functions with lexical scope, and garbage collection."

Direct link to the Go implementation of Starlark: https://github.com/google/starlark-go

For a Python-like syntax, https://github.com/google/starlark-go is the language used in Babel. It's very mature, but since it is used in a massive mature project with a specific purpose, it doesn't move fast or drift from the spec of its Java-based sibling. It doesn't have exception try except blocks or some other features you might expect, but for short extension logic, it might be exactly what you want with the stability you can depend upon.

Context: https://github.com/google/starlark-go/blob/cfacd890221418a2dc2c736f7b5e3476c38709b1/starlark/int_posix64.go

Thus envd is more like Dockerfile, while it uses a simplified python dialect starlark https://github.com/google/starlark-go as the build language.

Use Go (mostly for starlark-go)