- Installation is one command: the installer detects the platform, verifies SHA256, places the binary in ~/.whetuu/bin, and adds two lines to the shell config; running it twice has no effect.
- Uninstalling is simply rm -rf ~/.whetuu and removing the added lines; setting WHETUU_NO_MODIFY=1 prints the lines instead of writing them.
- The prompt displays contextual segments (user_host, directory, git branch/state/status, language logo with version, command duration, and a character that changes color on failure) and a history picker on the up arrow, which filters by directory and syntax-highlights commands.
- Performance is about 2 ms per render due to parallel I/O, with strict timeouts (250 ms for git, 200 ms for toolchain) to prevent hanging; even a 30-second hang is capped at 257 ms.
- Security is a priority: no network access, only two local files (history with mode 600, and a cache), no startup config file, all control bytes escaped, and subprocesses run with fixed arguments—never executing anything from the repository.