jk VS starlark-go

People have tried: https://github.com/jkcfg/jk

But yeah I agree. The thing is, if all you need is robust determinism why do you need a full functional language with currying and other complex concepts?

Google had the same problem for Bazel, and their solution (Starlark) is way easier to understand.

If I were writing a build system today (and I did just write one actually to test out some ideas) I would use Typescript for the language with something like jk to provide hermeticity. Typescript has many advantages, especially over Python, but mainly:

It's possible to sandbox most languages, and with some work you can probably make them deterministic too.

Here's an example: https://github.com/jkcfg/jk

That beats having to learn an entirely new language.

Maybe Javascript? A lot of web tools support Javascript config files. There's this nice-looking effort to provide a hermetic execution environment for them: https://github.com/jkcfg/jk and if you use Typescript you get an extremely good static type system too. Plus the language is already very well known with loads of tool support and documentation.

Definitely what I would use today.

If you think "but I need conditionals and file inclusion and ..." then maybe consider just allowing a full programming language instead. Someone pointed me to jk which looks like it is heading in the right direction, except that it outputs YAML by default for some insane reason.

You may be interested in jk. If you don't want to use a special purpose configuration language (jsonnet, cue, dhall, etc), this is a nice alternative that uses js in a hermetic runtime (but see their open issues for progress on that). They seem to also be adding native typescript support so you could even have type checking built-in.

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)