Layer	Choice
Language	Go 1.25+
TUI framework	bubbletea
Components	bubbles — spinner, progress, stopwatch
Forms	huh — select, multi-select, confirm
Styles	lipgloss
Config format	TOML
CLI lib	cobra
Encryption	age — backup payloads
Self-update	minio/selfupdate
Packaging	goreleaser → tarballs + install.sh

Repo layout

lfg/
├── cmd/
│   ├── lfg/main.go         thin entry — calls cli.Execute()
│   └── snap/main.go        screen → ANSI text helper for screenshots
├── internal/
│   ├── cli/                cobra subcommands (root, apply, backup, doctor, ...)
│   ├── preset/             bundle + tool data (built-in default + parser)
│   ├── detect/             binary + version probe (concurrent, timeout-bounded)
│   ├── installer/          brew/apt/mise/npm/custom + streaming exec
│   ├── backup/             tar + age snapshot pipeline
│   ├── doctor/             environment readiness checks
│   ├── state/              ~/.config/lfg/state.json
│   ├── version/            ldflags-injected build metadata
│   └── tui/
│       ├── app.go          screen state machine + global hotkeys
│       ├── theme.go        4 palettes + huh theme builder
│       ├── layout.go       Frame(): outer chrome, centering
│       ├── title.go        figlet logo + gradient sweep
│       ├── welcome.go      animated hero + numbered actions
│       ├── tree_picker.go  collapsible bundle/tool tree
│       ├── confirm.go      stats row + huh.Confirm
│       ├── progress.go     channel-driven log tail wired to installer
│       ├── done.go         next-steps card
│       ├── backup.go       huh.Confirm (encrypt) → spinner → result
│       └── quit_confirm.go huh.Confirm dialog (`q` from anywhere)
├── .goreleaser.yaml
├── .github/workflows/
└── install.sh

Screen state machine

internal/tui/app.go::Model holds a screen enum + a child model per screen. The root Update dispatches messages to the active child; child models request transitions by returning a transitionMsg cmd. The transition method re-instantiates the destination child model with current selection state so each screen always sees fresh, correct data.

Selection state flows screen → screen via two maps on the root model:

• selectedBundleIDs map[string]bool (set in bundle picker)
• selectedTools map[string]bool keyed <bundleID>/<toolName>

Adding a screen: extend the screen enum, add a child field on Model, register dispatch in Update/forwardSize/View/transition, and emit goTo(screenX) from wherever you trigger the transition.

Layout & chrome

Frame(palette, w, h, subtitle, inner, footer, compactTitle) is the single source of chrome. Every screen ends in a Frame call. Frame builds a fully closed bulletin box: top corners + side rules + bottom corners.

CanvasW(width) is the single source of truth for inner canvas width — every screen calls it instead of recomputing the formula inline. Bounds: 56 min, 100 max.

compactTitle is height < 22 — falls back from figlet banner to a single-line gradient lfg string. xs/sm test widths depend on this contract.