Difftastic is a command-line diff tool that understands code syntax, comparing files based on their structure rather than line-by-line differences. This approach produces diffs that are significantly easier for developers to read and understand.

Key capabilities include:

Syntax-aware comparison - Parses code to understand actual changes, not just line modifications. Formatting changes like line wrapping are ignored, showing only meaningful alterations
Accurate delimiter matching - Recognizes when code is wrapped in new delimiters and tracks changes within those wrappers
Real line numbers - Displays actual file line numbers before and after changes, eliminating cryptic diff notation
Broad language support - Works with C++, C#, Clojure, Dart, Erlang, Go, Haskell, Java, JavaScript, Kotlin, Lisp, Lua, OCaml, PHP, Python, R, Ruby, Rust, Scala, TypeScript and more
Multiple file formats - Handles HCL, HTML, JSON, YAML and additional formats
Git integration - Seamlessly works with Git workflows
Open source - Fully open source and available for modification and distribution

Difftastic solves the common problem where traditional diffs show formatting changes as modifications, making it harder to spot actual code logic changes. By understanding syntax structure, it provides clearer, more actionable diffs for code review and debugging.