fastpaste-rs

Clipboard history + snippet manager for Linux, written in Rust. Targets Wayland (KDE Plasma 6 / KWin). Global hotkeys are grabbed via XGrabKey on XWayland, so the session must have XWayland available. X11 sessions are not supported.

Features

• Main window: snippet/folder tree (CRUD) with an editor pane and toolbar
• Selection dialog: keyboard-driven quick-paste popup
• Options dialog: general / hotkeys / clipboard-history / paste settings, applied live (hotkey changes re-register immediately)
• Global hotkeys (defaults, configurable): Ctrl+U → selection dialog, Ctrl+Shift+U → main window; layout-independent physical-keycode grabs that work under any keyboard layout
• Clipboard history folder: bounded ring populated by watching the system clipboard (wlr-data-control), rendered as a virtual folder in the tree
• Paste via /dev/uinput Ctrl+V emulation, with the previous clipboard contents restored afterwards
• System tray icon with context menu (Slint native SystemTrayIcon)
• Localization: English, Russian, German, Spanish, Simplified Chinese
• Single-instance guard (abstract unix socket, kernel-released on exit)

Build prerequisites (Linux)

• Rust 1.95+ (rustup recommended)
• libfontconfig1-dev (required by Slint):

  sudo apt install libfontconfig1-dev
  

• A Wayland session (KDE Plasma 6 / KWin target) with XWayland available (global hotkeys grab via XGrabKey on the XWayland root window).
• For paste via /dev/uinput: the user must have read/write access to /dev/uinput. systemd-logind typically grants this via ACL on login for physical sessions; check with getfacl /dev/uinput.

Build

cargo build --release

Run

cargo run --release --bin fastpaste-gui

Workspace crates

Four crates layered bottom-up. app imports data + platform; gui imports all three (it uses data types and platform hotkey ids directly, not only through app):

fastpaste-data — storage layer

No GUI, no platform code, no I/O beyond SQLite.

• item.rs — Item / ItemKind: the snippet/folder value type that crosses all layers (plain copyable struct, serde + chrono timestamps)
• database.rs — Database: SQLite CRUD for items and folders
• error.rs — DataError, the layer's error enum
• migrations/ — refinery SQL migrations (V001__initial_schema.sql)

fastpaste-platform — Linux platform layer

Everything that touches the OS/desktop environment:

• hotkey.rs — GlobalHotkey trait + X11GlobalHotkey (XGrabKey on the XWayland root window, layout-independent physical keycodes), and the OPEN_DIALOG_ID / OPEN_MAIN_WINDOW_ID action ids
• clipboard.rs — Clipboard trait + ArboardClipboard (read/write via data-control) and the wl-clipboard-watch-based change watcher with an arboard-polling fallback
• uinput.rs — EvdevUinputCtrlV / NullUinputCtrlV: /dev/uinput Ctrl+V emulation, degrading gracefully when the device is unavailable
• take_once.rs — TakeOnceChannel, a one-shot hand-off primitive used by the hotkey event path

fastpaste-app — service layer

Orchestrates data + platform into long-lived services:

• context.rs — AppContext: composition root bundling every service behind Arc for the UI controllers, plus the single-instance guard
• settings.rs — Settings: typed config.toml load/save (confy), grouped into general / hotkeys / clipboard-history / paste sections
• clipboard_history.rs — ClipboardHistory: the bounded ring fed by the clipboard watcher, exposed as a virtual folder
• paster.rs — Paster: the paste sequence (set clipboard → delay → Ctrl+V via uinput → restore previous clipboard)
• paths.rs — single source of truth for XDG config_dir / data_dir

fastpaste-gui — Slint frontend (binary fastpaste-gui)

• ui/main_window.slint — snippet tree + editor + toolbar
• ui/selection_dialog.slint — the quick-paste popup
• ui/options_dialog.slint — settings dialog
• ui/tray_icon.slint — FastpasteTray (native SystemTrayIcon + menu)
• ui/widgets.slint — compact in-house widget set + design tokens
• ui/translations.slint — global singleton carrying every UI string
• src/tree_builder.rs — flattens Item rows + history entries into the TreeItem list consumed by the TreeView
• src/i18n.rs — fluent runtime (embedded .ftl, per-locale fallback, live language switch)
• src/main.rs — controllers wiring Slint callbacks/hotkey events to AppContext
• build.rs — slint_build compilation of the .slint files

Data & configuration

What	Path
Settings	~/.config/fastpaste/config.toml
Database	~/.local/share/fastpaste/fastpaste.sqlite

The config file is created on first save with these defaults. Missing fields fall back to their defaults, so a config written by an older version keeps loading after upgrades:

[general]
language = "system"          # "system" follows the OS locale; or a BCP-47 tag

[hotkeys]
open_dialog = "Ctrl+U"
open_main_window = "Ctrl+Shift+U"

[clipboard_history]
enabled = true
max_items = 10
position = "bottom"          # "top" | "bottom"

[paste]
delay_ms = 70                # pause between clipboard set and Ctrl+V
restore_clipboard = true     # put the previous clipboard back after paste

Dependencies

Shared versions are pinned in the workspace root Cargo.toml ([workspace.dependencies]); each crate pulls from there via dependency.workspace = true.

Crate	Used by	Purpose
slint	gui	Declarative UI toolkit: main window, dialogs, system tray
slint-tree-view	gui	Slint TreeView component for the snippet tree
slint-build	gui (build)	Compiles .slint files at build time; experimental-module-builds feature resolves import { TreeView } from "@TreeView" against the library crate
fluent-templates	gui	Fluent static loader: embeds the .ftl files at compile time, per-key fallback chain to English
sys-locale	gui	Resolves the "system" language setting from the OS locale
fluent-syntax	gui (dev)	Parses .ftl sources in the key-parity test
tracing	platform, app, gui	Structured logging
tracing-subscriber	gui	Log output with RUST_LOG env-filter support
anyhow	app, gui	Ergonomic error handling at the service/main level
thiserror	data, platform, app	Derive error enums for each layer's error type
rusqlite (features bundled, chrono)	data	SQLite driver; bundled builds the C library in, chrono gives native DateTime<Utc> ↔ TEXT conversion
refinery	data	SQL migrations (fastpaste-data/migrations/)
serde	data, app	Serialization: Item rows and config.toml
chrono	data, app, gui (dev)	Timestamps: RFC 3339 in the DB, history entry times
directories	app	XDG data_dir/config_dir resolution
confy	app	TOML config load/save
single-instance	app	Single-instance guard: abstract unix socket keyed on the data dir (no lock file, kernel-released on exit)
arboard (feature wayland-data-control)	platform	Clipboard read/write (set_text/text): native data-control protocol on Wayland — the same transport as the watcher — with arboard's X11 backend as fallback when the compositor offers no data-control
wl-clipboard-watch	platform	Event-driven clipboard change detection (ext/wlr-data-control); the platform layer falls back to arboard polling when neither protocol is available
evdev	platform	/dev/uinput virtual keyboard to emit Ctrl+V; KeyCode: FromStr also resolves hotkey key names to physical kernel keycodes
x11rb	platform	XGrabKey global hotkeys on XWayland — physical keycodes, layout-independent (the global-hotkey crate resolves keysyms via the core keymap and fails under Cyrillic layouts); GetModifierMapping resolves real Alt/NumLock/Super modifier bits
libc	platform	poll(2) for the hotkey reader's blocking loop (wakes on X traffic or a wake-pipe byte); already a transitive dep of x11rb
tempfile	data, app (dev)	Temp directories in tests
serde_json	data (dev)	Serde round-trip asserts in tests (enum #[serde(...)] attributes)

Version constraints worth knowing when upgrading:

• slint, slint-build, and slint-tree-view are all pinned in the workspace root [workspace.dependencies] and must stay on compatible versions — the TreeView library exports .slint types compiled against the same Slint compiler.
• fluent-templates 0.15 (fluent-bundle 0.16, fluent-syntax 0.12, unic-langid 0.9) and the dev-only fluent-syntax 0.12 share the same unic-langid-impl major; mixing older majors conflicts.
• wl-clipboard-rs (pulled in transitively by arboard's wayland-data-control feature) exposes no watch API in any published version — its watch surface lives only in the separate wl-clipboard-rs-tools binary (verified against docs.rs, 2026-08). Clipboard watching therefore stays on wl-clipboard-watch; don't "simplify" it away in favor of the transitive wl-clipboard-rs.

License

MIT — see LICENSE.