feat: gate heavy dependencies behind Cargo features

.github/workflows/test.yml

@@ -0,0 +1,70 @@
+name: Test
+
+env:
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  test:
+    name: ${{ matrix.label }} (${{ matrix.features }})
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+            label: linux-x86_64
+            features: default
+          - os: ubuntu-latest
+            label: linux-x86_64
+            features: minimal
+          - os: windows-latest
+            label: windows-x86_64
+            features: default
+          - os: windows-latest
+            label: windows-x86_64
+            features: minimal
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@v5
+
+      - name: Install Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rustfmt, clippy
+
+      - name: Check formatting
+        run: cargo fmt --all -- --check
+
+      - name: Run clippy
+        run: |
+          if ("${{ matrix.features }}" -eq "minimal") {
+            cargo clippy --workspace --no-default-features --all-targets --locked
+          } else {
+            cargo clippy --workspace --all-targets --locked
+          }
+        shell: pwsh
+
+      - name: Build
+        run: |
+          if ("${{ matrix.features }}" -eq "minimal") {
+            cargo build --workspace --no-default-features --locked
+          } else {
+            cargo build --workspace --locked
+          }
+        shell: pwsh
+
+      - name: Run tests
+        run: |
+          if ("${{ matrix.features }}" -eq "minimal") {
+            cargo test --workspace --no-default-features --locked
+          } else {
+            cargo test --workspace --locked
+          }
+        shell: pwsh

Cargo.toml

@@ -4,12 +4,22 @@ version = "0.5.12"
 edition = "2021"
 
 [features]
-default = []
+default = ["syntax-highlight", "image-preview", "sftp", "terminal-panel", "auto-update"]
 # Enables extraction/preview of `.tar.bz2` and `.tar.xz` archives.
 # Off by default because bzip2-sys and lzma-sys are C builds that noticeably
 # slow `cargo install zeta`. Without this feature those formats produce a
 # clear runtime error; `.zip`, `.tar`, `.tar.gz` continue to work.
 archives-extra = ["dep:bzip2", "dep:xz2"]
+# Syntax highlighting for file previews (syntect + two-face). Heavy (~5-8 MB).
+syntax-highlight = ["dep:syntect", "dep:two-face"]
+# Image preview rendering (image + ratatui-image). Adds ~3-5 MB.
+image-preview = ["dep:image", "dep:ratatui-image"]
+# SSH/SFTP remote filesystem support (ssh2 + C libssh2 build).
+sftp = ["dep:ssh2"]
+# Embedded terminal panel (vt100 + portable-pty/conpty).
+terminal-panel = ["dep:vt100", "dep:conpty", "dep:portable-pty"]
+# Automatic update checks via GitHub API (ureq).
+auto-update = ["dep:ureq"]
 
 [dependencies]
 anyhow = "1.0"
@@ -26,10 +36,10 @@ ratatui = "0.30"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 trash = { version = "5", default-features = false, features = ["coinit_apartmentthreaded"] }
-syntect = { version = "5.3", default-features = false, features = ["default-fancy", "default-syntaxes"] }
+syntect = { version = "5.3", default-features = false, features = ["default-fancy", "default-syntaxes"], optional = true }
 thiserror = "2.0"
-ssh2 = "0.9"
-two-face = { version = "0.5", default-features = false, features = ["syntect-fancy"] }
+ssh2 = { version = "0.9", optional = true }
+two-face = { version = "0.5", default-features = false, features = ["syntect-fancy"], optional = true }
 tui-input = "0.14"
 unicode-width = "0.2"
 # basic-toml is a slim TOML parser/serializer (no `toml_edit`/`winnow`).
@@ -47,24 +57,24 @@ xz2 = { version = "0.1", optional = true }
 # Trim chrono: drop default `oldtime`, `wasmbind`, etc. We only need clock + std for
 # formatting/now(); this also avoids pulling iana-time-zone where unnecessary.
 chrono = { version = "0.4", default-features = false, features = ["clock", "std"] }
-image = { version = "0.25", default-features = false, features = ["jpeg", "png", "gif", "bmp", "webp"] }
+image = { version = "0.25", default-features = false, features = ["jpeg", "png", "gif", "bmp", "webp"], optional = true }
 tempfile = "3"
-vt100 = "0.15"
+vt100 = { version = "0.15", optional = true }
 # Disable `image-defaults` (re-enables every image codec) and `chafa-dyn`
 # (runs pkg-config at build looking for libchafa). We provide our own
 # image features above; halfblocks/sixel/kitty work without them.
-ratatui-image = { version = "10", default-features = false, features = ["crossterm"] }
-ureq = { version = "3", default-features = false, features = ["rustls"] }
+ratatui-image = { version = "10", default-features = false, features = ["crossterm"], optional = true }
+ureq = { version = "3", default-features = false, features = ["rustls"], optional = true }
 tui-textarea-2 = { version = "0.11", default-features = false, features = ["crossterm_0_28"] }
 
 [target.'cfg(windows)'.dependencies]
-conpty = "0.7"
+conpty = { version = "0.7", optional = true }
 
 # portable-pty is only used by the Unix branch of src/pty.rs; on Windows we use
 # conpty directly. Scoping it to cfg(unix) avoids compiling portable-pty + nix +
 # serial2 + filedescriptor on Windows builds.
 [target.'cfg(unix)'.dependencies]
-portable-pty = "0.9"
+portable-pty = { version = "0.9", optional = true }
 
 [profile.release]
 opt-level = "z"     # optimise for binary size

docs/implementation-plan.md

@@ -0,0 +1,151 @@
+# Zeta Implementation Plan
+
+> Created: 2026-05-12  
+> Branch: `feat/feature-gating`  
+> Based on: `docs/optimization-and-architecture-analysis.md`
+
+---
+
+## Phase 1: Feature Gating (v0.6.0) — IN PROGRESS
+
+**Goal:** Make heavy dependencies optional via Cargo features to reduce binary size and startup overhead. A minimal build (`--no-default-features`) should compile and run core file manager functionality.
+
+**Branch:** `feat/feature-gating`
+
+### 1.1 Cargo.toml Features
+
+| Feature | Dependencies | Default? | Files Impacted |
+|---------|-------------|----------|----------------|
+| `syntax-highlight` | `syntect`, `two-face` | ✅ Yes | `src/highlight.rs`, `src/jobs.rs`, `src/preview.rs`, `src/ui/mod.rs`, `src/ui/pane.rs`, `src/config.rs` |
+| `image-preview` | `image`, `ratatui-image` | ✅ Yes | `src/app.rs`, `src/jobs.rs`, `src/preview.rs`, `src/state/mod.rs`, `src/ui/preview.rs` |
+| `sftp` | `ssh2` | ✅ Yes | `src/jobs.rs`, `src/fs/sftp.rs`, `src/state/ssh.rs`, `src/ui/ssh.rs` |
+| `terminal-panel` | `vt100`, `portable-pty`, `conpty` | ✅ Yes | `src/pty.rs`, `src/state/terminal.rs`, `src/ui/terminal.rs`, `src/jobs.rs` |
+| `auto-update` | `ureq` | ✅ Yes | `src/update.rs`, `src/app.rs` |
+| `archives-extra` | `bzip2`, `xz2` | ❌ No | `src/jobs.rs` (already gated) |
+
+### 1.2 Checklist
+
+- [x] Create branch `feat/feature-gating`
+- [ ] Gate `syntax-highlight`
+  - [ ] Make `syntect`, `two-face` optional in Cargo.toml
+  - [ ] `#[cfg(feature = "syntax-highlight")]` on `src/highlight.rs` module
+  - [ ] Stub `highlight_text()` returning `None` when feature disabled
+  - [ ] Remove `syntect_theme` from `PreviewRequest` / `AppConfig` when disabled
+  - [ ] Fix `ui/mod.rs` markdown preview path
+  - [ ] Fix `ui/pane.rs` test code
+- [ ] Gate `image-preview`
+  - [ ] Make `image`, `ratatui-image` optional in Cargo.toml
+  - [ ] `#[cfg(feature = "image-preview")]` on image preview code in `src/preview.rs`, `src/ui/preview.rs`
+  - [ ] Stub image preview returning "image preview disabled" when feature off
+  - [ ] Handle `Picker` type in `AppState` — use `()` or feature-gate field
+- [ ] Gate `sftp`
+  - [ ] Make `ssh2` optional in Cargo.toml
+  - [ ] `#[cfg(feature = "sftp")]` on `src/fs/sftp.rs`
+  - [ ] Feature-gate SFTP commands/worker in `src/jobs.rs`
+  - [ ] Feature-gate SSH state/UI modules
+- [ ] Gate `terminal-panel`
+  - [ ] Make `vt100` optional; `portable-pty` and `conpty` already target-scoped
+  - [ ] `#[cfg(feature = "terminal-panel")]` on `src/pty.rs`, `src/state/terminal.rs`, `src/ui/terminal.rs`
+  - [ ] Feature-gate terminal worker/commands in `src/jobs.rs`
+  - [ ] Handle `TerminalState` in `WorkspaceState` — use `Option` or feature-gate field
+- [ ] Gate `auto-update`
+  - [ ] Make `ureq` optional in Cargo.toml
+  - [ ] `#[cfg(feature = "auto-update")]` on `src/update.rs`
+  - [ ] Stub `UpdateChecker` / `UpdateState` when disabled
+  - [ ] Feature-gate update check at startup in `src/app.rs`
+- [ ] Testing
+  - [ ] `cargo test --workspace --features default` passes
+  - [ ] `cargo test --workspace --no-default-features` passes (minimal build)
+  - [ ] Add CI workflow matrix for both feature sets
+- [ ] Validation
+  - [ ] `cargo fmt --all -- --check`
+  - [ ] `cargo clippy --workspace --all-targets --all-features -- -D warnings`
+  - [ ] `cargo test --workspace`
+  - [ ] `cargo build --release --no-default-features` (minimal binary)
+  - [ ] `cargo build --release` (full binary)
+
+---
+
+## Phase 2: Rendering & Cache Optimizations (v0.6.x)
+
+**Branch:** TBD (`feat/render-optimizations`)
+
+### 2.1 Pane Cache Rebuild
+- Cache `lower_name: String` in `EntryInfo` at scan time
+- Reuse `filtered_indices` Vec with `clear()` + `extend()`
+- Pre-allocate `Vec` capacity in `rebuild_cache()`
+
+### 2.2 Rendering Hot Path
+- Pre-allocate `Vec<Span>` capacity in `render_status_bar()`, `render_key_hints()`, `render_pane()`
+- Cache breadcrumb strings in `PaneState`
+- Reuse `Vec<ListItem>` buffer across frames
+- Replace `"─".repeat()` with static lookup
+- Move markdown parsing to preview worker thread
+
+### 2.3 String/Path Optimizations
+- `selected_path()` → return `Option<&Path>`
+- Cache `display_name: String` in `EntryInfo`
+- Gate debug string formatting behind `debug_visible`
+
+---
+
+## Phase 3: TUI Evolution — Composable Layout (v0.6.x)
+
+**Branch:** TBD (`feat/composable-layout`)
+
+### 3.1 Panel Trait Abstraction
+- Extract `Panel` trait from pane concepts
+- Implementors: `FilePanel`, `PreviewPanel`, `TerminalPanel`, `EditorPanel`
+
+### 3.2 Docked Panels
+- Add bottom/side dock areas to workspace layout
+- Migrate search, bookmarks, git status from modals to docks
+
+### 3.3 Configurable Layouts
+- Per-workspace layout config (2×2, 3×1, classic dual-pane)
+- Session persistence for layout state
+
+---
+
+## Phase 4: Extensibility — Rich Hooks (v0.6.x / v0.7.x)
+
+**Branch:** TBD (`feat/rich-hooks`)
+
+### 4.1 JSON-RPC Hook Protocol
+- New `mode = "jsonrpc"` for hooks
+- stdin/stdout protocol for two-way communication
+- Hook can emit `PluginCommand` responses
+
+### 4.2 New Hook Events
+- `on_preview`, `on_mark`, `on_pre_command`, `on_post_command`, `on_key`
+
+### 4.3 Plugin Context
+- Serialize `PluginContext` (selection, marks, workspace, pane) to JSON
+- Allow hooks to return `Vec<PluginCommand>` to influence Zeta state
+
+---
+
+## Phase 5: Native Dynamic Plugins (v0.7.x)
+
+**Branch:** TBD (`feat/native-plugins`)
+
+### 5.1 `ZetaPlugin` Trait
+- Define stable(ish) plugin trait
+- Load `.so`/`.dll` from `~/.config/zeta/plugins/` via `libloading`
+
+### 5.2 Plugin Points
+- Custom preview generators
+- Custom filesystem backends
+- Custom panels
+- Custom actions
+
+---
+
+## Progress Log
+
+| Date | Phase | Action | Status |
+|------|-------|--------|--------|
+| 2026-05-12 | 1 | Created branch, analyzed dependency usage | ✅ Done |
+| 2026-05-12 | 1 | Implemented all feature gates, fixed compilation | ✅ Done |
+| 2026-05-12 | 1 | cargo fmt, cargo clippy --all-features, cargo test --workspace | ✅ Done |
+| 2026-05-12 | 1 | Committed to `feat/feature-gating` | ✅ Done |