Zero-dependency RFC 6902 JSON Patch engine for computing, applying, and inverting structural differences between JSON documents. The diff(a, b) function produces a minimal patch using index-based or LCS array strategies; applyPatch applies it; revertPatch undoes it; and invertPatch creates an inverse patch. A HistoryManager provides undo/redo with configurable depth and branch truncation on new edits. A SyncManager handles optimistic concurrency: apply local changes speculatively, then reconcile when the server responds. RFC 6901 JSON Pointer parsing and formatting is exposed as a standalone path module. Use this package for collaborative editing, undo/redo stacks, change-event streams, and any system where you need to track or transmit the delta between two object states rather than the full state itself.

Documentation tree

diff — (no submodules)
- diff — (no submodules)
errors — (no submodules)
- diff-error — (no submodules)
history — (no submodules)
- history — (no submodules)
operations — (no submodules)
- operations — (no submodules)
patch — (no submodules)
- patch — (no submodules)
path — (no submodules)
- path — (no submodules)
sync — (no submodules)
- sync — (no submodules)
utils — (no submodules)
- utils — (no submodules)

- [diff](./src/diff/diff.md) — _(no submodules)_- [errors](./src/errors/diff-error.md) — _(no submodules)_- [diff-error](./src/errors/diff-error.md) — _(no submodules)_- [history](./src/history/history.md) — _(no submodules)_- [history](./src/history/history.md) — _(no submodules)_- [operations](./src/operations/operations.md) — _(no submodules)_- [operations](./src/operations/operations.md) — _(no submodules)_- [patch](./src/patch/patch.md) — _(no submodules)_- [patch](./src/patch/patch.md) — _(no submodules)_- [path](./src/path/path.md) — _(no submodules)_- [path](./src/path/path.md) — _(no submodules)_- [sync](./src/sync/sync.md) — _(no submodules)_- [sync](./src/sync/sync.md) — _(no submodules)_- [utils](./src/utils/utils.md) — _(no submodules)_- [utils](./src/utils/utils.md) — _(no submodules)_- [diff](./src/diff/diff.md) — _(no submodules)_- [errors](./src/errors/diff-error.md) — _(no submodules)_- [diff-error](./src/errors/diff-error.md) — _(no submodules)_- [history](./src/history/history.md) — _(no submodules)_- [history](./src/history/history.md) — _(no submodules)_- [operations](./src/operations/operations.md) — _(no submodules)_- [operations](./src/operations/operations.md) — _(no submodules)_- [patch](./src/patch/patch.md) — _(no submodules)_- [patch](./src/patch/patch.md) — _(no submodules)_- [path](./src/path/path.md) — _(no submodules)_- [path](./src/path/path.md) — _(no submodules)_- [sync](./src/sync/sync.md) — _(no submodules)_- [sync](./src/sync/sync.md) — _(no submodules)_- [utils](./src/utils/utils.md) — _(no submodules)_- [utils](./src/utils/utils.md) — _(no submodules)_- [diff](./src/diff/diff.md) — _(no submodules)_- [errors](./src/errors/diff-error.md) — _(no submodules)_- [diff-error](./src/errors/diff-error.md) — _(no submodules)_- [history](./src/history/history.md) — _(no submodules)_- [history](./src/history/history.md) — _(no submodules)_- [operations](./src/operations/operations.md) — _(no submodules)_- [operations](./src/operations/operations.md) — _(no submodules)_- [patch](./src/patch/patch.md) — _(no submodules)_- [patch](./src/patch/patch.md) — _(no submodules)_- [path](./src/path/path.md) — _(no submodules)_- [path](./src/path/path.md) — _(no submodules)_- [sync](./src/sync/sync.md) — _(no submodules)_- [sync](./src/sync/sync.md) — _(no submodules)_- [utils](./src/utils/utils.md) — _(no submodules)_- [utils](./src/utils/utils.md) — _(no submodules)_- [diff](./src/diff/diff.md) — _(no submodules)_- [errors](./src/errors/diff-error.md) — _(no submodules)_ - [diff-error](./src/errors/diff-error.md) — _(no submodules)_- [history](./src/history/history.md) — _(no submodules)_ - [history](./src/history/history.md) — _(no submodules)_- [operations](./src/operations/operations.md) — _(no submodules)_ - [operations](./src/operations/operations.md) — _(no submodules)_- [patch](./src/patch/patch.md) — _(no submodules)_ - [patch](./src/patch/patch.md) — _(no submodules)_- [path](./src/path/path.md) — _(no submodules)_ - [path](./src/path/path.md) — _(no submodules)_- [sync](./src/sync/sync.md) — _(no submodules)_ - [sync](./src/sync/sync.md) — _(no submodules)_- [utils](./src/utils/utils.md) — _(no submodules)_ - [utils](./src/utils/utils.md) — _(no submodules)_

Packages

Module	Description
`./path`	RFC 6901 JSON Pointer parsing, formatting, and path utilities
`./utils`	Deep clone, equality, hashing, and document path navigation
`./operations`	RFC 6902 operation types, factories, validation, and inversion
`./diff`	Structural diff producing minimal JSON Patch (index and LCS strategies)
`./patch`	RFC 6902 patch application and revert with OTel integration
`./history`	Linear undo/redo history manager
`./sync`	Optimistic concurrency sync manager
`./errors`	Structured error class with stable code registry

Quick Start

import { diff, applyPatch, createHistory, revertPatch } from "@suaveplan/diff";
import type { JsonValue } from "@suaveplan/diff";

let doc: JsonValue = { name: "Alice", age: 30, tags: ["a", "b"] };
const history = createHistory({ maxEntries: 100 });

// Compute and apply a patch
const next: JsonValue = { name: "Alice", age: 31, tags: ["a", "b", "c"] };
const patch = diff(doc, next);
doc = applyPatch(doc, patch).doc;
history.push(patch);

// Undo
const undoPatch = history.undo()!;
const snapshot = { name: "Alice", age: 30, tags: ["a", "b"] }; // pre-patch state
doc = revertPatch(doc, undoPatch, snapshot);

Installation

bun add @suaveplan/diff

License

MIT