Colla

Rust-native Operational Transformation primitives for immutable nested values.

The published colla library supports Rust 1.81 or newer. Coordinated JavaScript releases support Node.js 22+, Vite 5+ and Rollup 4+.

The core model is a closed Value tree and one recursive, canonical Change. It provides functional Apply, sequential Compose, pairwise Transform (TP1), Invert, snapshot-aware ChangeBuilder, and a strict canonical binary body codec.

use colla::{apply, path, Value};

let before = Value::map([("title", Value::text("Draft"))])?;

let mut builder = before.change();
builder.text_insert(&path!["title"], 5, " v2")?;
let change = builder.build();
let after = apply(&before, &change)?;

Design specifications:

• docs/data-model.md
• docs/ot-properties.md
• docs/binary-format.md
• Core roadmap
• Release runbook
• Changelog
• colla-ot JavaScript package

Run Rust tests with cargo test --workspace and JavaScript artifact tests with pnpm test:js.