Directory

Open Source Packages

Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.

5929 packages

All Packages

45Health
Library npm

formula-parser

A JavaScript library that parses and evaluates Excel-style formulas and mathematical expressions.

648
MIT
Used by 1
84Health
Library PyPI

primp

Python HTTP client that impersonates real browser TLS and HTTP/2 fingerprints.

598
MIT
Used by 1
76Health
Library Composer

Mail MIME Parser

Testable, PSR-compliant PHP library for parsing RFC 822/2822/5322 email messages, MIME parts, headers, and attachments.

551
Other
Used by 1
46Health
Library Cargo

native-tls

A safe, ergonomic Rust wrapper over each platform's native TLS implementation.

546
Other
Used by 1
65Health
Library Cargo

rss

Serialize and deserialize the RSS web content syndication format in Rust.

502
Apache 2.0
Used by 1
53Health
Library Cargo

bpaf

Lightweight, flexible Rust command line argument parser with derive and combinatoric APIs.

462
Other
Used by 1
74Health
Library Cargo

mail-parser

Zero-copy, RFC 5322/MIME-conformant e-mail parsing library for Rust with no required dependencies.

456
Other
Used by 1
37Health
Library npm

hjson-js

A human-friendly JSON superset with comments, quoteless strings, and optional commas — parse and stringify config files without sacrificing readability.

432
MIT
Used by 1
74Health
Library Cargo

rasn

A safe, #[no_std] ASN.1 codec framework for Rust that encodes and decodes BER, CER, DER, PER, OER, JER, and XER from one abstract data model.

385
Other
Used by 1
34Health
Library npm

dirty-json

A permissive JSON parser that recovers valid data from malformed, hand-edited, or scraped JSON strings.

334
AGPL 3.0
Used by 1
80Health
Library npm

ASN1.js

A pure JavaScript/TypeScript library for encoding and decoding ASN.1 BER/DER data, the foundation of X.509 certificates and PKI.

300
BSD 3
Used by 1
38Health
Library Cargo

fast-float

A zero-dependency Rust crate that parses decimal strings into f32/f64 up to 8x faster than the standard library, with full no_std support.

293
Other
Used by 1
51Health
Library Cargo

tree-sitter-elixir

The official Elixir grammar for Tree-sitter, powering fast, incremental parsing for editors and tooling.

284
Apache 2.0
Used by 1
43Health
Library npm

react-js-cron

Customizable React component for visually editing cron expressions with Ant Design

279
MIT
Used by 1
62Health
Library Cargo

speedate

Fast and simple datetime, date, time, and duration parsing for Rust.

252
MIT
Used by 1
46Health
Library PyPI

luqum

Parses Lucene query syntax into a Python AST you can inspect, transform, and convert into native ElasticSearch JSON DSL queries.

203
Other
Used by 1
39Health
Library Cargo

hyper-tls

A minimal HTTPS connector that pairs hyper with native-tls for secure Rust HTTP clients.

201
Apache 2.0
Used by 1
63Health
Library Cargo

tree-sitter-kotlin

A Tree-sitter grammar for Kotlin, validated against JetBrains' own PSI parser and shipped as native bindings for six languages.

191
MIT
Used by 1
42Health
Library PyPI

lkml

A fast, dependency-free Python parser and serializer for Looker's LookML modeling language.

186
MIT
Used by 1
44Health
Library Cargo

tree-sitter-solidity

A low-dependency Tree-sitter grammar for Solidity, designed for metaprogramming and tooling.

186
MIT
Used by 1
53Health
Library Cargo

html5gum

A WHATWG-spec-compliant HTML5 tokenizer for Rust with pluggable emitters, letting you trade convenience for near-zero-allocation performance.

171
MIT
Used by 1
47Health
Library npm

prisma-ast

Parse, query, and modify Prisma schema files as an AST in JavaScript while preserving comments and formatting.

167
MIT
Used by 1
32Health
Library npm

node-logfmt

A logfmt (key=value) parser, stringifier, and structured logger for Node.js, with Express/restify body-parsing middleware and a CLI.

163
MIT
Used by 1
38Health
Library npm

acorn-typescript

An Acorn plugin that extends the fast JavaScript parser with TypeScript, JSX/TSX, and decorator syntax.

154
MIT
Used by 1

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