Smaller, faster, dependency-free parsers you can drop in for the libraries you already use. Change one import and keep your code.

Packages · Switching · Size and speed · Docs

Packages

Package	Reads and writes	Bundle, gzip	Replaces
tinyaml	YAML	7.7 KiB	js-yaml 4 and 5, yaml 2, yamljs, @std/yaml
tinyjson5	JSON5	3.4 KiB	json5 2.2.3
tinyini	INI	1.3 KiB	ini 1.3.8, 2 to 4.0 and 4.1.3 to 7, @one-ini/wasm 0.1.1 to 0.2

Bundle sizes include every export of each package's root API, minified and gzipped. See Size and speed for the drop-in replacements.

Each package is published on its own, so install only the ones you use:

pnpm add tinyaml tinyjson5 tinyini

Switching

The quickest way is the codemod. Run it in your project:

npx tinyswap

It finds the libraries you use, picks the tiny subpath that matches each installed version, and asks which ones to migrate. It shows the files it will change, then rewrites the imports and requires, swaps the dependencies in package.json, and offers to run your install. It covers js-yaml, yaml, yamljs, @std/yaml, json5, strip-json-comments, jsonc-parser, comment-json, jju, ini and @one-ini/wasm. pnpm dlx tinyswap and bunx tinyswap work too, and you can pass a directory, which defaults to the current one.

It won't write to a project outside git or with uncommitted changes unless you pass --force. --yes migrates everything it finds without asking, --dry-run prints the diff and writes nothing, --only js-yaml,json5 limits it to those libraries, and --help lists the flags.

To switch by hand, change the import. The calls, options, output and errors stay the same.

- import yaml from "js-yaml";
+ import yaml from "tinyaml/js-yaml";

- import JSON5 from "json5";
+ import JSON5 from "tinyjson5/json5";

- import ini from "ini";
+ import ini from "tinyini/ini";

Each package matches its original on that library's own tests and on tens of thousands to millions of fuzzed inputs, and lists every place it still differs.

Size and speed

You use	Switch to	Size, gzip	Parses	Stringifies
js-yaml 4	tinyaml/js-yaml	14.4 → 11.6 KiB	1.6× faster	1.7× faster
js-yaml 5	tinyaml/js-yaml-v5	17.0 → 16.1 KiB	1.5× faster	1.8× faster
yaml 2	tinyaml/yaml	29.8 → 16.9 KiB	12.0× faster	2.8× faster
yamljs	tinyaml/yamljs	8.8 → 8.1 KiB	5.1× faster	1.1× faster
@std/yaml	tinyaml/std	11.2 → 10.7 KiB	2.4× faster	1.6× faster
json5 2.2.3	tinyjson5/json5	7.5 → 3.2 KiB	7.4× faster	4.7× faster
json5 1.0.2	tinyjson5/json5-v1	8.3 → 3.3 KiB	7.1× faster	5.1× faster
strip-json-comments 3	tinyjson5/strip-json-comments	0.7 → 0.5 KiB	3.8× faster	—
strip-json-comments 2	tinyjson5/strip-json-comments-v2	0.6 → 0.5 KiB	4.2× faster	—
strip-json-comments 5	tinyjson5/strip-json-comments-v5	0.6 → 0.6 KiB	3.6× faster	—
jsonc-parser 3.3.1	tinyjson5/jsonc-parser	6.6 → 5.7 KiB	1.2× faster	—
comment-json 4.6.2	tinyjson5/comment-json	35.3 → 18.2 KiB	1.8× faster	1.3× faster
jju 1.4.0	tinyjson5/jju	9.6 → 9.5 KiB	1.1× faster	1.6× faster
ini 7.0.0	tinyini/ini	1.6 → 1.5 KiB	1.8× faster	2.9× faster
ini 2.0.0	tinyini/ini-v2	1.4 → 1.4 KiB	1.6× faster	1.6× faster
ini 1.3.8	tinyini/ini-v1	1.4 → 1.4 KiB	1.6× faster	1.7× faster
@one-ini/wasm 0.2.1	tinyini/one-ini	36.0 → 1.7 KiB	12.4× faster	—
@one-ini/wasm 0.1.1	tinyini/one-ini-v0.1	32.3 → 1.7 KiB	12.1× faster	—

For new code, the root tinyaml API is 7.7 KiB, 1.9× smaller than js-yaml 4 and 3.9× smaller than yaml 2. It parses 18.7× faster than yaml 2 and stringifies 12.9× faster.

Size is the minified bundle, gzipped. Speed is the median time to parse and stringify each package's large benchmark file. @one-ini/wasm's size adds its .wasm file, gzipped, and its speed is parse_to_uint32array on a 100 KB .editorconfig. strip-json-comments only strips comments, so its time is the time to strip them. Measured on Apple M4, Node 26.13.0.

ini is already small, so the tinyini entries that replace it save little and win on speed. Each package's README has the full results and the inputs they come from.

Develop

A pnpm workspace with Node 26, pnpm 12, and Vite+ (vp) for formatting, linting, tests and builds.

pnpm install
pnpm build    # every package
pnpm check    # format, lint and typecheck every package
pnpm test     # every package's tests
pnpm fixtures # download what the comparisons and benchmarks run against
pnpm drop-ins # fetch fixtures, measure every package again into .github/drop-ins.json, then pnpm readme
pnpm readme   # rewrite the badges and drop-in tables in every README with automd
pnpm brand    # redraw the logo, favicons and banners from .github/scripts/brand.ts

The logo is the 🤏 emoji as Noto Emoji draws it, under the Apache License 2.0.

All packages share one version and release together.

License

MIT, by @onmax.