Use when working on TaTUÍ's ANSI backend or event parser: SGR styling, cursor movement, raw mode, alt screen, mouse capture, or decoding input escape sequences. Triggers: ANSI, escape sequence, SGR, CSI, termios, raw mode, alt screen, cursor move, color degradation, mouse, bracketed paste.
Use when implementing or testing TaTUÍ's layout engine: Constraint, Rect splitting, the solver, spacing/margins, or the layout cache. Covers constraint semantics, integer rounding, and cache keying. Triggers: layout, constraint, split, rect, flex, percentage, ratio, fill, solver.
Use when writing or updating TaTUÍ tests: TestBackend usage, golden snapshot format, layout truth-tables, the allocation invariant test, or ANSI parser fuzzing. Triggers: test, snapshot, golden, TestBackend, unittest, truth-table, allocation test, fuzz.
Use when working on TaTUÍ's render path: Buffer, Cell, diffing, the terminal tick loop, or backend dispatch. Covers allocation-free steady state, buffer swapping, and the immediate/retained boundary. Triggers: buffer, diff, tick, render path, allocation, swap, double buffering.
Use when porting any widget, layout, buffer, or backend behavior from ratatui to TaTUÍ. Covers the parity-map workflow, semantic-diff checks, and which Rust idioms NOT to copy (traits, lifetimes, CompactString, macros). Triggers: port, parity, ratatui equivalent, faithful, mirror behavior.
Use when handling text, graphemes, or cell width in TaTUÍ: Span/Line/Text, wide (CJK/emoji) characters, the cell skip flag, or grapheme segmentation. Triggers: unicode, grapheme, wide char, CJK, emoji, width, skip flag, combining, ZWJ.