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

42Health
Library npm

clsx

A tiny, fast utility for conditionally constructing className strings

9,838
MIT
Used by 256
83Health
Library npm

class-variance-authority

A tiny TypeScript utility for building type-safe, variant-driven className APIs on top of clsx.

6,888
Apache 2.0
Used by 190
75Health
Library Cargo

serde_json

The de facto standard JSON library for Rust, built on the Serde serialization framework

5,636
Apache 2.0
Used by 111
76Health
Library Cargo

serde

A generic framework for serializing and deserializing Rust data structures efficiently and safely.

10,825
Other
Used by 108
73Health
Library Go

testify

The essential Go toolkit for assertions, mocks, and structured test suites.

26,203
MIT
Used by 102
93Health
Framework Cargo

Tokio

The async runtime powering most of Rust's networked, concurrent, and I/O-bound applications.

33,150
MIT
Used by 95
84Health
Library Cargo

reqwest

An ergonomic, batteries-included HTTP client for Rust, with async and blocking APIs.

11,821
Other
Used by 70
92Health
Library npm

undici

A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies

7,695
MIT
Used by 70
59Health
Library npm

classnames

A tiny utility for conditionally joining CSS class names together.

17,777
MIT
Used by 68
73Health
Library Cargo

tempfile

A secure, cross-platform Rust library for temporary files and directories that clean up automatically on drop.

1,463
Other
Used by 68
67Health
Library Cargo

base64

Correct, fast, and configurable base64 encoding and decoding for Rust, with pluggable alphabets and padding.

736
Apache 2.0
Used by 66
55Health
Framework Go

Cobra

The commander library that powers Kubernetes, Hugo, and GitHub CLI's command-line interfaces.

44,603
Apache 2.0
Used by 62
67Health
Library Go

jwt

A zero-dependency Go implementation of JSON Web Tokens (JWT) with pluggable HMAC, RSA, RSA-PSS, ECDSA, and Ed25519 signing methods.

9,225
MIT
Used by 62
79Health
Library Cargo

regex

Rust's finite-automata regex engine with guaranteed linear-time matching and no catastrophic backtracking.

4,024
Apache 2.0
Used by 58
79Health
Library Cargo

Chrono

Timezone-aware date and time handling for Rust, with correct calendar operations and flexible strftime-style formatting.

3,907
Other
Used by 58
90Health
Library Cargo

Clap

The most widely used command-line argument parser for Rust, with both derive and builder APIs.

16,707
Other
Used by 56
85Health
Library Cargo

uuid

Generate and parse UUIDs in Rust across every standardized version, from v1 to v8.

1,242
Other
Used by 56
90Health
Tool npm

SWC

Rust-based JavaScript/TypeScript compiler, a drop-in super-fast alternative to Babel

34,191
Apache 2.0
Used by 55
70Health
Library Cargo

sha2

Pure Rust implementation of the SHA-2 hash function family (SHA-224/256/384/512) with hardware-accelerated backends.

2,265
Other
Used by 55
58Health
Library Cargo

tracing

Structured, application-level diagnostics for async Rust programs, built around scoped spans and events.

6,873
MIT
Used by 51
93Health
Library PyPI

urllib3

A powerful, user-friendly HTTP client for Python with thread-safe connection pooling, TLS verification, and retry handling.

4,058
MIT
Used by 48
68Health
Library npm

proxy-agent

Maps HTTP, HTTPS, SOCKS, and PAC proxy protocols to the correct Node.js http.Agent implementation automatically.

1,161
MIT
Used by 47
90Health
Tool PyPI

Ruff

An extremely fast Python linter and code formatter, written in Rust, built as a drop-in replacement for Flake8, Black, isort, and dozens of plugins.

49,630
MIT
Used by 46
90Health
Library npm

Prisma Client

Auto-generated, type-safe database client for Node.js and TypeScript.

47,610
Apache 2.0
Used by 46

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