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Communities · Documentation & Learning
Y Combinator's tech news and discussion community.
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Communities · Documentation & Learning
Y Combinator's tech news and discussion community.
Color Tools
Curated palettes shown in context on a real website.
Communities · Documentation & Learning
Blogging platform for developers with custom domains.
Passwords & IDs · Security
Check if your email or password has appeared in known data breaches.
Headers & CSP · Security
Mozilla's scanner that grades a site's security headers and config.
API Mocking · API Tools
HTTP request and response service for testing clients.
Illustrations & Assets · Design & Prototyping
Free modular people illustrations by Pablo Stanley — rotate limbs and mix outfits in a friendly flat style.
Design Systems · Design & Prototyping
Apple's design guidelines for iOS, macOS and other platforms.
Regex
Collection of ready-made regex snippets with visual explanations.
APM & Tracing · Monitoring & Observability
Open-source distributed tracing platform, CNCF graduated.
Minifiers · Developer Utilities
Free online JavaScript minifier with API access.
References · Documentation & Learning
The Modern JavaScript Tutorial — the deepest free JS reference from basics to advanced browser APIs.
CI/CD · DevOps
The classic open-source automation server for CI/CD.
JSON · Data Formats
Advanced JSON editor with tree view, query, transform and diff.
JSON · Data Formats
Format, validate, minify and view JSON online.
JSON · Data Formats
Beautiful, shareable JSON viewer with previews for many data types.
JSON · Data Formats
Official site of the JSON Schema specification, with tools and validators.
JSON · Data Formats
The classic JSON validator and formatter.
API Mocking · API Tools
Free fake REST API for prototyping and testing.
Notebooks & Data Science · Data & Analytics
The standard interactive notebooks for data science and ML.
JWT · Encoding & Decoding
The official JSON Web Token site: decode, debug and find libraries.
Inspiration & Galleries · Design & Prototyping
Jon Yablonski's collection of UX maxims (Hick's Law, Fitts's Law…) with citations and practical takeaways.
Generators · CSS Tools
Interactive CSS Grid layout builder with code export.
Cheatsheets & Learning · Git & Version Control
Interactive visualization game for learning Git branching.