Write modern, idiomatic Go (1.21–1.26) using the standard library and current language features instead of legacy patterns. Covers slices/maps/cmp, the min/max/clear builtins, range-over-int and range-over-func iterators, errors.Is/As/Join and %w wrapping, generics, new(expr), omitzero, os.Root, slog, and the stdlib APIs that are now the recommended idiom. Use this skill BEFORE writing or editing any Go (.go) code, reviewing a Go diff, or picking a stdlib API — it replaces the legacy forms this project's lint rules ban (the old sort package, interface{}, manual index loops, append([]T(nil), …), ptr() helpers, hand-rolled min/max). Complements the `lo` skill, which owns functional transforms (Map/Filter/Reduce/GroupBy); reach here for everything stdlib- and language-level. Invoke whenever the task is "write some Go", "clean this Go up", "is there a stdlib way to do this", or CLAUDE.md says "Modern Go style".
Write modern, expressive Go using samber/lo — the generic functional toolkit. Use when writing transforms (Map, Filter, Reduce, GroupBy, KeyBy), set operations (Intersect, Difference, Union), error-aware variants (*Err), or replacing manual for+append loops. Covers Python/JS-to-Go idiom translation. Invoke for any slice/map transform, collection pipeline, or when CLAUDE.md says "use lo".
Style, measure, and lay out terminal UI content with charmbracelet/lipgloss v2. Covers the render pipeline, layout composition (Join/Place), sizing discipline (Width vs MaxWidth, frame-size accounting), borders, alignment, color system, table/tree/list sub-packages, canvas/compositor, and common measurement pitfalls. Use whenever styling TUI output, debugging layout/overflow bugs, building tables or trees, or compositing layered content.
Build terminal user interfaces with Go and Bubbletea framework. Use for creating TUI apps with the Elm architecture, dual-pane layouts, accordion modes, mouse/keyboard handling, Lipgloss styling, and reusable components. Includes an effects/animation reference, teatest integration-testing patterns, and battle-tested layout rules from real projects.