Jsonnet[1] and kapitan[2] are the tools I currently use. Their learning curve is not optimal (and I tried to contribute to smoothen it with a jsonnet course[3] and a 'get started wit kapitan' blog post[4]), but once used to it it's hard to do without, and their combination makes them even more useful (esp. If you deploy K8s). In Ruud's case, Jsonnet might have been worth looking at as Hashicorp tools can be... - Source: Hacker News / 5 months ago

Kubernetes config is a decent example. I had ChatGPT generate a representative silly example -- the content doesn't matter so much as the structure: https://gist.github.com/cstrahan/528b00cd5c3a22e3d8f057bb1a75ea61 Now consider 100s (if not 1000s) of such files. I haven't given Pkl an in depth look yet, but I can say that the Industry Standard™ of "simple YAML" + string substitution (with delicate, error prone... - Source: Hacker News / 5 months ago

Maybe you'd like jsonnet: https://jsonnet.org/ I find it particularly useful for configurations that often have repeated boilerplate, like ansible playbooks or deploying a bunch of "similar-but" services to kubernetes (with https://tanka.dev). Dhall is also quite interesting, with some tradeoffs: https://dhall-lang.org/ A few years ago I did a small comparison by re-implementing one of my simpler ansible... - Source: Hacker News / 10 months ago

Apologies for the lack of context, and for missing this comment until today. Both are tools for defining kubernetes manifests (which are YAML) in a reusable manner. Jsonnet is a formally specified extension of JSON. It’s essentially a functional programming language (w/some object oriented features) that generates config files in JSON/YAML/etc, so it’s straightforward to determine whether an input file is valid,... - Source: Hacker News / about 1 year ago

I like Google's Jsonnet [1], which has all of this except for 4. Jsonnet is quite mature, with fairly wide language adoption, and has the benefit of supporting expressions, including conditionals, arithmetic, as well as being able to define reusable blocks inside function definitions or external files. It's not suitable as a serialization format, but great for config. It's popular in some circles, but I'm sad that... - Source: Hacker News / about 1 year ago

Have a look on Rex - https://rexify.org, in addition to dsl like constructs it is just pure perl. It also doesn't need any dependencies on the managed host, just perl and ssh. Source: over 2 years ago

Since I feel that rex needs more attention, here is a small example from $work using rex. Needed to quickly reconfigure a number of Ubuntu hosts with netplan to use static ip addresses instead of DHCP. Source: about 3 years ago