Multi Launcher

Multi Launcher is a lightweight application launcher for Windows built with Rust and eframe. The project targets Windows exclusively. It supports configurable hotkeys, basic plugin architecture and file indexing to quickly open applications or files.

Use Cases

• Launch installed applications or custom commands from anywhere using a single hotkey.
• Search your clipboard history or saved bookmarks to quickly paste or open items.
• Run shell commands without opening a terminal.
• Perform web searches or look up documentation directly.
• Jump to frequently used folders with the folders plugin.
• Set timers or alarms from the launcher. Type timer or alarm and press Enter to open the creation dialog.
• Keep track of quick todo items or notes.
• Insert saved text snippets, add new ones with cs add <alias> <text> or edit them with cs edit.
• Monitor network traffic with the net command.
• Control media playback using the media prefix.
• Trigger sequences of commands through the macro plugin.
• Capture screenshots to a file or the clipboard.
• Switch between open browser tabs.
• Check local and public IP addresses.
• Generate random numbers, dice rolls or passwords.
• Create lorem ipsum filler text or search for emoji.
• Convert text between cases like snake_case or camelCase.
• Pick colors and copy them as hex, RGB or HSL values.
• Track time with a built-in stopwatch or open the Windows Task Manager.

Building

Requirements:

• Rust toolchain

cargo build --release

To capture CapsLock reliably and suppress its normal toggle, build with the optional unstable_grab feature. Without this feature some systems may ignore the CapsLock hotkey:

cargo build --release --features unstable_grab

This feature is defined in Cargo.toml and enables the underlying rdev capability used to grab keyboard events.

For debugging, enable Debug logging in the settings window. When this option is active, you can further adjust the verbosity by setting the RUST_LOG environment variable before running the program:

$env:RUST_LOG="info"; cargo run --release --features unstable_grab

Enable persistent log files by adding a log_file entry to settings.json. Set it to true to create launcher.log next to the executable or supply a custom path.

If hotkeys do nothing, check the output for warnings starting with Hotkey listener failed. When using CapsLock as the hotkey you almost always need to build with --features unstable_grab so the listener can grab the key.

Settings

Multi Launcher automatically creates a settings.json file next to the binary on first run. Edit this file or open the Settings window to customise the launcher. The default hotkey is F2. To use a different key, set the hotkey value as shown below:

{
  "hotkey": "F2",
  "quit_hotkey": "Shift+Escape",
  "help_hotkey": "F1",
  "enabled_plugins": [
    "web_search",
    "calculator",
    "unit_convert",
    "clipboard",
    "bookmarks",
    "folders",
    "shell",
    "runescape_search",
    "weather",
    "system",
    "timer",
    "macros",
    "history",
    "help"
  ],
  "enabled_capabilities": {"folders": ["search", "show_full_path"]},
  "note_save_on_close": false,
  "enable_toasts": true,
  "fuzzy_weight": 1.0,
  "usage_weight": 1.0,
  "debug_logging": false,
  "log_file": true,
  "offscreen_pos": [2000, 2000],
  "window_size": [400, 220],
  "query_scale": 1.0,
  "list_scale": 1.0,
  "history_limit": 100,
  "clipboard_limit": 20,
  "preserve_command": false,
  "clear_query_after_run": false,
  "follow_mouse": true,
  "static_location_enabled": false,
  "static_pos": [0, 0],
  "static_size": [400, 220],
  "screenshot_dir": "./MultiLauncher_Screenshots",
  "screenshot_save_file": true
}

The hotkey value accepts a base key with optional modifiers separated by +. Examples include "Ctrl+Shift+Space" or "Alt+F1". Supported modifiers are Ctrl, Shift and Alt. Valid keys cover alphanumeric characters, function keys (F1-F12) and common keys like Space, Tab, Return, Escape, Delete, arrow keys and CapsLock.

quit_hotkey can be set to another key combination to close the launcher from anywhere. If omitted, the application only quits when the window is closed through the GUI. help_hotkey toggles a quick overlay listing commands. Set it to null or uncheck the Enable help hotkey box in the Settings window to disable this shortcut.

offscreen_pos specifies where the window is moved when hiding it. Choose coordinates outside the visible monitor area so the window stays accessible but off-screen. The default is [2000, 2000].

window_size stores the size of the launcher window when it was last closed. The window is restored to this size on the next start. The default is [400, 220] if the value is missing.

When follow_mouse is true the window is centered on the mouse cursor whenever it becomes visible. To keep the launcher at a specific position instead, set follow_mouse to false and enable static_location_enabled. Provide the desired coordinates in static_pos and optionally a fixed size via static_size. The Settings window now includes a Snapshot button to capture the current window position and size for these fields.

query_scale and list_scale control the size of the search field and the results list separately. Values around 1.0 keep the default look while higher numbers enlarge the respective element up to five times. enable_toasts controls short pop-up notifications when saving settings or commands. Set it to false to disable these messages. note_save_on_close automatically saves the contents of note panels whenever the window closes—whether you press Esc, click the close button, or trigger another close event. The default is false. Toggle this behaviour from the Settings window via the "Save note on close (Esc)" checkbox in the Note section. fuzzy_weight and usage_weight adjust how results are ranked. The fuzzy weight multiplies the match score while the usage weight favours frequently launched actions. Setting "fuzzy_weight": 0 in settings.json forces case-insensitive substring matching across all plugins. Command aliases are checked first and a matching alias ranks above other results.

Example: typing test will only list entries containing test. If an alias matches this word it appears before the other results. history_limit defines how many entries the history plugin keeps. clipboard_limit sets how many clipboard entries are persisted for the clipboard plugin. preserve_command keeps the typed command prefix (like bm add or f add) in the search field after running an action. clear_query_after_run removes the search text after a successful action whenever you prefer starting with a blank box. enabled_capabilities maps plugin names to capability identifiers so features can be toggled individually. The folders plugin, for example, exposes show_full_path. screenshot_dir sets the directory used when saving screenshots. If omitted, screenshots are stored in a MultiLauncher_Screenshots folder in the current working directory. screenshot_save_file determines whether screenshots copied to the clipboard are also written to disk. The default is true.

If you choose CapsLock as the hotkey, the launcher suppresses the normal CapsLock toggle when compiled with the unstable_grab feature enabled. Press Shift+CapsLock to change the keyboard state while the application is running. The launcher only responds when CapsLock is pressed on its own; any other modifier keys will simply toggle the caps lock state without showing the window.

Plugins

flowchart LR
    A[Hotkey pressed] --> B(Show launcher)
    B --> C{User query}
    C --> D[Plugin manager searches]
    D --> E[Display results]
    E --> F[Run action]

Loading

graph TD
    S[Startup] --> B1[Register built-in plugins]
    S --> B2[Load plugin_dirs]
    B2 --> L[Load dynamic plugins]
    B1 --> PM[Plugin manager ready]
    L --> PM

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Built-in commands:

Prefix	Example	Description
g	g rust	Google web search
=	= 2+2	Calculator
conv	conv 10 km to mi	Unit and base conversions
drop	drop 1/128 128	Drop rate calculator
rs/osrs	rs item	RuneScape Wiki search
yt	yt rust	YouTube search
red	red cats	Reddit search
wiki	wiki rust	Wikipedia search
cb	cb list	Clipboard history
bm	bm add <url>	Manage bookmarks
f	f add <path>	Folder shortcuts
o	o list	Omni search
sys	sys shutdown	System actions
ps	ps	Process list
info	info cpu	System information
net	net	Network usage
ip	ip	Show IP addresses
sh	sh echo hi	Shell commands
hi	hi	Search history
note	note add <text> or note rm <slug>	Quick notes
todo	todo add <task>	Todo items
todo edit	todo edit	Edit todos
todo export	todo export	Export todos
cs	cs add <alias> <text>	Text snippets
macro	macro list	Command macros
rec	rec	Recycle Bin cleanup
tmp	tmp new [name] or tmp create [name]	Temporary files
ascii	ascii text	ASCII art
emoji	emoji smile	Emoji search
case	case hello world	Text and encoding conversions
color	color #ff0000	Color picker and formats
ts	ts 0	Timestamp conversion
tsm	tsm 3600000	Midnight timestamp
rand	rand number 10	Random numbers, dice and passwords
app	app <filter>	Saved apps
vol	vol 50	Volume control (vol pid <pid> <level>; dialog lists processes on Windows)
media	media play	Media controls
bright	bright 50	Adjust brightness
tm	tm	Task Manager
win	win <title>	Window management
ss	ss clip	Screenshot capture
help	help	Command overview
sw	sw start	Stopwatch
timer	timer add 5m tea	Timers
alarm	alarm 07:30	Alarms
weather	weather Berlin	Weather lookup

Timers and alarms are stored in alarms.json and reload automatically when the launcher starts. The timer plugin exposes a completion_dialog capability that toggles pop-up notifications when a timer completes.

Stopwatches use the sw prefix. Start one with sw start, stop it with sw stop or reset it via sw reset. Right click a stopwatch entry to copy the elapsed time. A precision option in the Settings window controls how many decimals are displayed.

sequenceDiagram
    participant U as User
    participant L as Launcher
    participant T as Timer Plugin
    U->>L: "timer add 5m tea"
    L->>T: store timer
    T-->>L: confirm
    T->>L: timer finished
    L->>U: show notification

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Conversion Plugins

The conv/convert prefix now covers two plugins:

• Unit Convert handles common units like length, mass, temperature, volume, area, speed, pressure, energy, power, data, time, fuel economy and angles. Examples:

  conv 1 kwh to j
  conv 8 bit to byte
  conv 30 mpg to kpl
  conv 180 deg to rad
  

• Base Convert translates between binary, hexadecimal, octal, decimal and plain text:

  conv 1010 bin to hex
  conv ff hex to bin
  conv "hello" text to hex
  conv 48656c6c6f hex to text
  conv 42 dec to bin
  

Volume Plugin

Control system volume or specific processes:

vol 75
vol pid 1234 50
vol name notepad.exe 20

On Windows, opening the volume dialog (vol) also lists running applications with sliders to adjust each process just like the system volume mixer.

Screenshot Plugin

Use ss to capture the active window, a custom region or the whole desktop. Add clip to copy the result to the clipboard. Screenshots are saved in a MultiLauncher_Screenshots folder in the current working directory by default or the path set in screenshot_dir. Set screenshot_save_file to true to always keep a file when copying to the clipboard.

sequenceDiagram
    participant U as User
    participant L as Launcher
    participant P as Screenshot Plugin
    U->>L: "ss clip"
    L->>P: capture screen
    P-->>L: image path
    L->>U: save/copy

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Text Case Plugin

Convert text to different cases. Example:

case Hello World

The plugin shows many variations including uppercase, lowercase, capitalized, camelCase, PascalCase, snake_case, SCREAMING_SNAKE_CASE, kebab-case, Train-Case, dot.case and space case. It also offers alternating, mocking, inverse and backwards cases, acronym and initial forms, sentence and title case, Base64/hex/binary encodings, ROT13, clap and emoji text, custom delimiters and Morse code. Select any variant to copy it to the clipboard.

Macros Plugin

The macros plugin runs a saved sequence of launcher commands. Macros are stored in macros.json and can be edited by typing macro to open the editor.

macro list
macro example

Random Plugin

Generate random numbers, dice rolls or passwords with the rand prefix. Examples:

rand number 10
rand dice
rand pw 8

IP Plugin

Display local network interface addresses with the ip prefix. Append public to also retrieve the public IP via api.ipify.org.

Color Picker Plugin

Type color to open an interactive picker or specify a hex value such as color #ff0000. The plugin outputs the selected color in multiple formats: #RRGGBB, rgb(r, g, b) and hsl(h, s%, l%). Use the arrow keys to highlight a format and press Enter to copy it to the clipboard.

Notes Plugin

Manage quick Markdown notes with the note prefix. The editor window includes an Open externally button to open the current note in another program. A setting under the Note plugin labelled Open externally chooses the default opener: WezTerm, Powershell, Notepad or Neither to be asked each time. WezTerm is supported and is the default external editor. The Powershell option uses PowerShell 7 when available (listed as "Powershell" in the menu) and falls back to powershell.exe.

When the search box is empty the launcher shows these shortcuts along with app <alias> entries for saved actions.

Selecting a clipboard entry copies it back to the clipboard. Type help and press Enter to open the command list. The help window groups commands by plugin name and can optionally display example queries. Additional plugins can be added by building shared libraries. Each plugin crate should be compiled as a cdylib and export a create_plugin function returning Box<dyn Plugin>:

#[no_mangle]
pub extern "C" fn create_plugin() -> Box<dyn Plugin> {
    Box::new(MyPlugin::default())
}

Place the resulting library file in one of the directories listed under plugin_dirs in settings.json.

Plugins can be enabled or disabled from the Settings window. The list of active plugins is stored in the enabled_plugins section of settings.json. The Plugin Settings dialog enables or disables plugins and toggles capabilities like show_full_path.

Changes take effect immediately once the dialog is closed. Use this window to enable additional plugins as they become available. A plugin to expose environment variables is planned for a future release.

Example:

{
  "enabled_plugins": [
    "web_search",
    "calculator",
    "clipboard",
    "bookmarks",
    "folders",
    "shell",
    "runescape_search",
    "system",
    "processes",
    "network",
    "weather",
    "timer",
    "media",
    "macros",
    "history",
    "help"
  ]
}

The folders plugin recognises the f prefix. Use f add <path> to add a folder shortcut and f rm <pattern> to remove one via fuzzy search. Custom entries can be aliased by right clicking them in the results list. Hovering a folder result shows its full path. A plugin setting "show full path always" controls whether the full path is displayed next to an alias or only as a tooltip. The bookmarks plugin uses the bm prefix. Use bm add <url> to save a link, bm rm to list and remove bookmarks (optionally filtering with a pattern) or bm list to show all bookmarks. Searching with bm <term> matches both URLs and aliases. The omni search plugin uses the o prefix to search folders, bookmarks and saved apps at once. Use o list to show all entries or o list <query> to filter them. The system information plugin uses the info prefix. Type info to show CPU, memory and disk usage or info cpu for a single metric. Other handy prefixes include ip to show local and public addresses, tab to switch browser tabs, rand for random numbers, dice rolls or passwords, and lorem for filler text. Use emoji to search emoji or kaomoji, case to transform text casing, sw for a stopwatch, ss to capture screenshots, tm to open the Windows Task Manager and settings to bring up the settings dialog.

Security Considerations

The shell plugin runs commands using the system shell without sanitising input. Only enable it if you trust the commands you type. Errors while spawning the process are logged. Type sh in the launcher to open the shell command editor for managing predefined commands. Saved commands can also be added with sh add <name> <command>, removed via sh rm <pattern> or listed with sh list.

Editing Apps

The launcher stores its custom actions in actions.json next to the executable. This file is created automatically the first time you save an app. While running the application you can manage this list through Edit Apps. Open the launcher with the configured hotkey and choose Edit Apps from the menu. Use the New App button to open the Add App dialog where you enter a label, description and the executable path. Enable Add arguments to supply extra command line parameters. The Browse button lets you select the file interactively. Existing entries can be edited via the Edit button or by right clicking an app in the results list and choosing Edit App. Apps can also be removed from the list. All changes are written to actions.json immediately.

Type app <filter> in the launcher to search these saved entries. Typing app alone lists all saved apps.

Packaging

The project can be compiled for Windows using cargo build --release. Afterwards bundle the binary for distribution using a Windows packaging tool such as cargo wix. When compiled this way the executable is built with windows_subsystem = "windows", which prevents an extra console window from appearing.

Troubleshooting

When diagnosing hotkey issues it can be helpful to enable info level logging:

$env:RUST_LOG="info"; cargo run

Tips

• Press the help hotkey (F1 by default) to display a quick list of available commands.
• Right click a folder result to set a custom alias for easier access.
• Right click a note entry to edit, remove, or open it in Neovim. The note editor's Open externally button uses the configured default opener.
• On Windows, Neovim launches via Powershell (PowerShell 7 when available), then powershell.exe, falling back to cmd.exe.
• Use the Snapshot button in Settings when adjusting static window placement.
• Searches are case-insensitive and also match on command aliases.
• Tweak fuzzy_weight and usage_weight if you want results to favour name matches or past usage differently.

Manual Test Plan

1. Build and run the project with cargo run.
2. Before the launcher window appears, press the configured hotkey once.
3. Observe the log output. There should be a message indicating a visibility change was queued.
4. When the GUI finishes initialising, it should immediately apply the queued visibility change and the window becomes visible. A log entry confirms this.
5. Press the hotkey again to ensure normal toggling after start-up.

On Windows the launcher also checks which virtual desktop the window belongs to whenever it becomes visible. If it is on another desktop it is automatically moved to the active one before being shown.