Show HN: Twain, a diff viewer like Meld, but for the age of AI

Developer andunieee released Twain, a GTK 4 diff viewer built as a Meld alternative for reviewing AI-generated code changes, available as a binary, Flatpak bundle, or via `cargo install --git https://github.com/andunieee/twain`. Twain shows all files from a Git diff sequentially in one view with a fast file tree, tree-sitter-based syntax highlighting, full-file or changed-only display with granular revealing of unchanged parts, and full-diff search, and it lets users comment on sets of changes and lines that AI agents can read and extend from a CLI via `twain comment --help`. Unlike Meld, Twain lacks merge, three-way comparisons, support for other version control systems, and direct file editing.

A diff viewer for people who love Meld, but wanted it to be slightly different. Things that are like Meld: - intuitive and nice view of what changed to what, what was removed from where and added where; - scrolling minimaps of changes; - git support; - fast. Things we have that Meld doesn't: - all files from a Git diff shown in the same view, sequentially; - a file tree on the side, super fast; - show either the full files or only the parts that changed, with granular revealing of the unchanged parts; - tree-sitter-based syntax highlighting; - the ability to comment on sets of changes and lines, and AIs can read these comments and add more from a CLI, like Hunk; - the ability to search through the entire set of modified files. Thins Meld has that we don't: - merge; - three-way comparisons; - support for other version control systems; - ability to edit the files directly. Run twain in your project's directory. It can also compare other Git revisions, but that doesn't matter much for now. Select lines and press C or right-click the mouse to leave a comment on them. Tell your AI agent to look into twain comment --help so it can participate. Download a binary or a Flatpak bundle from the latest release https://github.com/andunieee/twain/releases/latest or build from source needs GTK 4, GtkSourceView 5 and libadwaita : cargo install --git https://github.com/andunieee/twain