Hello, HN!<p>quicktype generates types and serializers from JSON, JSON Schema, TypeScript, and GraphQL queries, to help you use JSON type-safely in many languages: C#, Go, Rust, Crystal, C++, Objective-C, Java, TypeScript, JavaScript, JavaScript PropTypes, Flow, Swift, Kotlin, Elm, JSON Schema, Ruby, Dart, Python, Pike, and our latest language, Haskell.<p>quicktype has some remarkable features that differentiate it from other JSON converters:<p><i>Type inference</i>: quicktype infers optionals, dates, UUIDs, enums, integers, and unions. It also infers maps (versus objects) using a Markov chain.<p><i>Careful naming</i>: quicktype’s naming system creates nice, legal, unique names for types and properties, handling reserved words and tricky corner cases (e.g. `{ “”: “this is legal”, “null”: “so is this”, "1;DROP TABLE users”: “and this" }`).<p><i>Unions for heterogeneous data</i>: JSON data is often heterogenous. quicktype infers this, and creates union types in languages that support them, or synthetic union types in languages that don’t (e.g. try quicktyping `[0, “zero”]` as Swift and Go).<p><i>Type unification</i>. This works across multiple samples, so you can quicktype a directory of API data, for example, and unify types across all responses (e.g. you’ll get just one `Customer` type, even if customer data occurs in many samples). You can also provide multiple samples for the same type for better coverage.<p><i>Marshalling code</i>: In addition to types, quicktype generates functions for marshalling your types to and from JSON.<p><i>Supports dynamic languages</i>: quicktype can add dynamic typechecks for JavaScript, TypeScript, Flow, Python, and Ruby.<p><i>Convenient CLI</i>: Run `quicktype <a href="https://blockchain.info/latestblock" rel="nofollow">https://blockchain.info/latestblock</a> -o LatestBlock.ts` to quicktype a Bitcoin API in TypeScript.<p><i>Private hosted app</i>: <a href="https://app.quicktype.io/" rel="nofollow">https://app.quicktype.io/</a> runs quicktype on the client, so servers never see your data (most JSON converters send your JSON to their server)<p><i>Typed input</i>: Feed quicktype TypeScript or JSON Schema instead of JSON for better control over generated types.<p><i>Code quality</i>: quicktype emits clean code