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

36Health
Library npm

later

Composable library for defining recurring schedules and calculating their next or previous occurrences.

149
MIT
Used by 1
78Health
SDK npm

@tryghost/content-api

Official JavaScript client for Ghost's Content API, wrapping posts, pages, tags, authors, tiers, newsletters, and offers in a small promise-based interface.

134
MIT
Used by 1
41Health
Library npm

ansicolor

A dependency-free JavaScript library for ANSI color styling, parsing, and ANSI-to-CSS/Chrome DevTools conversion.

126
Other
Used by 1
49Health
Framework npm

UI-Router Core

Framework-agnostic state machine for URL-driven routing, transitions, and nested views in JS SPAs.

125
MIT
Used by 1
35Health
Library npm

ieee754

Read and write IEEE 754 floating-point numbers to and from a Buffer or array-like object.

122
BSD 3
Used by 1
32Health
Library npm

string-similarity-js

A lightweight, zero-dependency string similarity function using the Sorensen-Dice coefficient.

109
MIT
Used by 1
73Health
Tool npm

rails-erb-loader

A webpack loader that compiles embedded Ruby (.erb) templates into JavaScript for Rails projects.

105
MIT
Used by 1
74Health
SDK npm

Logto JS Core SDK

The framework-agnostic TypeScript core that powers Logto's entire JavaScript SDK family for OIDC authentication.

96
MIT
Used by 1
70Health
Library Cargo

wreq-util

Browser and OkHttp client emulation, TLS certificate compression, and delay middleware for the wreq HTTP client.

90
Apache 2.0
Used by 1
47Health
Library npm

@dr.pogodin/react-helmet

Thread-safe document head management for React 19 with tag deduplication, SSR support, and SEO tag prioritization.

86
Apache 2.0
Used by 1
33Health
Library npm

haversine-distance

A zero-dependency JavaScript implementation of the Haversine formula for great-circle distance between two coordinates, in meters.

83
MIT
Used by 1
72Health
Library npm

Protovalidate (ECMAScript)

Runtime validation for Protobuf messages, driven by buf.validate rule annotations in your .proto schema.

83
Apache 2.0
Used by 1
25Health
Library npm

js-string-escape

Escapes strings into safe JavaScript string literals, correctly handling quotes, backslashes, and all four ECMAScript line-terminator characters.

71
MIT
Used by 1
38Health
Library npm

final-form-arrays

Array mutators for Final Form that add push, pop, insert, remove, move, swap, and more to manage dynamic list fields.

70
MIT
Used by 1
70Health
SDK npm

flagsmith-js-client

The official JavaScript and React Native client SDK for Flagsmith, the open source feature flag and remote configuration platform.

67
BSD 3
Used by 1
80Health
SDK npm

commercetools Platform SDK

Fully-typed TypeScript client for every commercetools Composable Commerce API endpoint, generated straight from the platform's RAML spec.

65
MIT
Used by 1
28Health
Library npm

truncate

A tiny zero-dependency JavaScript utility that truncates text to a length while keeping URLs and email addresses intact.

52
MIT
Used by 1
28Health
Library npm

focus-options-polyfill

Polyfill for the focusOptions preventScroll flag on HTMLElement.focus().

47
MIT
Used by 1
22Health
Library npm

regexp.escape

A robust, spec-compliant polyfill for RegExp.escape() that safely escapes regex special characters, working as far down as ES3.

44
MIT
Used by 1
64Health
Framework npm

@tryghost/api-framework

A composable request pipeline that runs Ghost's API controllers through validation, serialization, permissions, and query stages.

37
MIT
Used by 1
37Health
Library npm

memory-level

In-memory abstract-level database for Node.js and browsers, backed by a fully persistent red-black tree.

36
MIT
Used by 1
51Health
SDK npm

configcat-js

Official JavaScript SDK for evaluating ConfigCat feature flags and remote config values directly in the browser.

34
MIT
Used by 1
22Health
Library npm

weakmap-polyfill

A lightweight, spec-compliant ES6 WeakMap polyfill for browsers and JS engines without native support.

32
MIT
Used by 1
24Health
Library npm

simple-xml-to-json

A tiny, dependency-free library that transpiles XML into JSON through an AST.

30
MIT
Used by 1

Join founders buildingwith open source

Opinionated takes, migration guides, cost-saving tips, and insights from the open source ecosystem.

Subscribe on Substack
Join 750+ subscribers