SOML – A Config Format for Humans

(github.com)

41 points | by microflash 2 hours ago

17 comments

  • layer8 3 minutes ago
    > what you see is what you get: […] '10.20' and 10.20 are a string and a float, exactly as written.

    This seems both underspecified and incorrect. Assuming a single-precision binary IEEE 754 floating-point number, 10.20 is actually 10.19999980926513671875. With double precision, it would be 10.199999999999999289457264239899814128875732421875. So what you see is not what you get, and it’s also unclear what exactly you’ll get.

  • umvi 1 minute ago
    > durations like 30s are real values, so nobody has to guess the unit of timeout: 30

    I would argue that it's better to always keep units baked into the key.

    If you have:

       timeout_s: 30
    
    Then unit information will never be lost, because the unit is always marshalled as a part of the key name and you don't have to worry if the target language has a duration type or not.

    If you have:

       timeout: 30s
    
    Then unit information probably won't be lost, but could in the following scenarios:

    - Target language doesn't have duration types (looking at the list - Ruby?)

    - If you ever need to convert to/from JSON

    So basically you have to use SOML across your entire stack and always use languages that have duration, and also never have to serialize to/from JSON (which also seems unlikely if you have to interface with external APIs).

    Go into more specialized software domains like radiology and you simply can't include units as a part of the value:

       dose_cgy: 2.5
  • ActionHank 5 minutes ago
    Gotta be honest, any time there's a solution like there that makes it more "human" they've just removed the structure / syntax.

    I'm guessing so you don't need to learn them, so then anyone off the street can edit the files, but it will break so bad without those guardrails, usually in some non-obvious way.

    Leading us back to inventing some new "human" thing, but with more implicit rules, and the cycle continues.

  • Yasuraka 5 minutes ago
    > no key needs quotes

    > 'the name': 'quotes are the escape hatch, when a key needs spaces'

    To quote David Fincher:

    > They know you have computers and can show a Tyrannosaurus Rex eat a car, so they know you can do anything. The question is: what don't you do, not what do you do.

    Constraints liberate; I wish people tended to more strictness. I had plenty of stumbling over "features", asking myself who couldve ever needed them. This particular one also irked me about CUE.

    But that's just a nit.

  • lightandlight 1 hour ago
    Ironically the project seems LLM-generated.

    I don't want to read Claude's interpretation of why your project matters. I want you to tell me directly.

    • functionmouse 16 minutes ago
      > your project

      there's a very good chance there's no human involvement at all in this

  • joshheitzman 14 minutes ago
    From the comments here I can infer that it has a schema and in turn I can extrapolate that this is as much "for humans" as many other config formats that are deterministically parseable.

    A GUI is a config format for humans as it can you show what all of the configuration options are along with text that tells you what they do.

  • catlifeonmars 19 minutes ago
    There are numerous inaccuracies in the “Why not TOML” section of the README. Here are a few:

    > CVE-2026-44244 injected a [core] section into .git/config for code execution.

    Git config is not TOML. It’s an ini-based bespoke syntax

    > SOML needs quotes for a literal dot.

    So does TOML, the dot notation is for nested keys. You use quotes for a literal dot.

    ——

    FWIW I like the decision to have a first class duration type.

  • james_marks 1 hour ago
    From the title, I thought this was a specification for configuring humans. I don't quite know what that means, and I'm disappointed still not to know.
    • VTimofeenko 15 minutes ago
      Could probably compile it into CRISPR editing spec
  • CodesInChaos 1 hour ago
    What I'm missing:

    1. The readme doesn't make it clear what its "float" type is. A double, a decimal, implementation defined. I'm generally not a fan of restricting numbers to what a double can represent, like toml does.

    2. It doesn't have a good way to model key-value pair like types such as tagged unions, polymorphic types, or function invocations. Simply allowing a key-value pair as a value (right associative) where the key is a string matching the keys of an object would fix this. Alternatively a function call syntax would fix this, which would also enable tuples as a concept distinct from arrays.

    • bjacobso 52 minutes ago
      The tagged-union / function-call point is where I keep ending up too. Once a config needs “one of these shapes” or “this thing with these arguments”, data formats grow conventions on top (type: keys, YAML !tags, $ref), and every consumer reimplements them.

      I’ve been building Forma (https://forma-lang.com), a small typed Lisp aimed at that zone. Everything is (head args...), so a tagged value and a call are the same syntax, and you declare the vocabulary yourself:

        (job nightly-export
          :schedule "0 3 * * *"
          :retry (backoff :max 5))
      
      job and backoff are forms you define with typed holes. The checker reports errors at the line you wrote, even after macro expansion. The output is plain JSON (or generated Effect TypeScript, but could target any language), so the app reading it doesn’t embed the language.
  • priomsrb 44 minutes ago
    Looks nice!

    It would be great if you had a simple website that allowed you to enter SOML and see the JSON side-by-side (similar to typescript playground https://www.typescriptlang.org/play/).

  • jll29 1 hour ago
    Looks like Windows *.ini format except ":" instead of "="...
    • CodesInChaos 1 hour ago
      Not really. INI has a fixed structure (section>key>value) and its values are untyped.
  • sscaryterry 1 minute ago
    We really don't need yet another format.
  • petre 47 minutes ago
    We already have TOML and it's great. I can seamlessly upgrade from ini to toml.
    • catlifeonmars 13 minutes ago
      TOML is probably my go-to these days.

      I think where TOML shines is when your configuration schema is relatively flat and simple. If you want to heavily nest configuration it can quickly get difficult to read. I’d love a more limited version of TOML that restricts the nesting depth.

    • microflash 31 minutes ago
      There's a comparison [0] where some differences are explained.

      [0]: https://github.com/soml-lang/soml/blob/main/comparison.md

  • drvd 1 hour ago
    So a stripped down variant of cue? Why not use cue directly?
    • brianm 1 hour ago
      Cue only really exists in go, and has a dependency chain to make maven weep.

      I think cue is better thought of as a language you use to generate JSON (or yaml, or, let's be honest, k8s flavored yaml) configs rather than a config language you use in your app.

  • esafak 1 hour ago
    Can you add README sections for the schema and supported types?
  • paulddraper 1 hour ago
    > Top-level arrays. A TOML file is always a table, so a list of records needs a wrapper key.

    I'm curious for example configs that are top-level lists?

    • priomsrb 10 minutes ago
      One example could be something that's a list of files/folders e.g. .gitignore

      Or it could be a list of records:

      {name: 'Alice', age: 42}

      {name: 'Bob': age: 44}

  • arionmiles 1 hour ago
    See also: HUML [1]

    1: https://huml.io/