Syntax highlighting
TextMate grammars (via tm4e) for 21 languages: Java, Python, Rust, Go, Kotlin, C/C++, C#, Ruby, SQL, Markdown, and more.
Highlighting uses TextMate grammars (via tm4e) for 21 languages (Java, XML, shell, PowerShell, DOS batch, Python, Groovy, Kotlin, Ruby, C, C++, Rust, Go, C#, Markdown, JSON, CSS, HTML, YAML, INI, and SQL) plus TypeScript/JavaScript, PHP, Lua, Dockerfile, Terraform, TOML, and more added alongside their language servers.
Tokenization is stateful (it carries grammar state across lines, so block comments and heredocs highlight correctly) and incremental, an edit re-tokenizes only from the changed line, off the UI thread. Token colors are themed per editor theme.
Bracket-pair colorization
Each (), [] and {} is tinted by how deeply it is nested, so “how far in am I?” is readable without counting. It answers a different question from the matching-bracket highlight — which is “where does this one close?” — and the two combine on the same character.
Brackets inside strings and comments are skipped. That is not a nicety: a stray { in a string would otherwise shift the colour of every bracket below it, which reads as the feature being broken rather than as one bracket being wrong. The depth pass rides the tokenize that was happening anyway, so it costs no extra repaint. On by default; Settings → Editor turns it off.