Dart

Dart is a statically typed, open-source language created at Google and first released in 2011 as a structured alternative to JavaScript. Its path changed in 2018 when Flutter adopted Dart as its only language, shifting Dart's main audience from web developers to cross-platform mobile and desktop app developers.

Multi-target compilation is central to the language. Dart compiles ahead of time (AOT) to native machine code (ARM, x64, RISC-V) for mobile and desktop, to JavaScript for the web, and to WebAssembly for modern browsers. During development a just-in-time (JIT) compiler powers hot reload, applying code changes to a running app in under a second without losing state.

The type system has sound null safety: variables cannot be null unless declared nullable (String?), and the compiler enforces it, removing a whole class of null-pointer errors. Dart 3 added pattern matching, records, sealed classes, and class modifiers, alongside generics, extension methods, mixins, and idiomatic async/await built on Future and Stream.

For concurrency, Dart uses isolates rather than shared-memory threads. Each isolate has its own heap and communicates by message passing, which rules out data races by design but requires copying or transferring data between isolates.

Packages come from pub.dev, which is strong for Flutter (UI components, state management, platform plugins) but much thinner than npm or PyPI for server-side and data work. Dart releases follow Flutter's roughly quarterly schedule, and the 3.x series keeps strong backward compatibility.