A native Windows command center for parallel coding agents.
GPU terminal core · split workspaces · live agent state · local automation
Releases · Product requirements · Capability parity · Agent hooks · Development · Security
Paramux is a native Windows terminal built for running Claude Code, Codex CLI, Gemini CLI, OpenCode, and ordinary shells side by side. It combines the session model of tmux, the agent-oriented workspace ideas popularized by cmux and wmux, and a real GPU-rendered terminal instead of an xterm.js WebView.
Each pane is an independent ConPTY session. Tabs group related workspaces, while the left sidebar answers the questions that matter when several agents are running at once:
- Which pane needs me?
- Which agent finished or failed?
- What repository, branch, directory, and ports belong to this pane?
- How do I jump to it without cycling through every terminal?
Paramux is a fork of the native Windows work from winghostty and retains Ghostty's terminal, font, and OpenGL rendering core. Winghostty and Ghostty are technical lineage and compatibility names; Paramux is the product and executable.
- Native Win32 shell on Windows 10/11 with ConPTY and OpenGL 4.3 rendering.
- Independent panes, horizontal/vertical splits, tabs, drag-to-resize dividers, pane zoom, session restore, and native context menus.
- Always-visible split-right, split-down, and settings buttons with hover tooltips, plus zoom, equalize, and merge-panes actions in the menus.
- Drag-and-drop pane rearrangement: drag a sidebar row onto a pane edge to dock it there, onto a pane center (or another row) to swap, with a live translucent drop preview.
- Native settings window (Ctrl+, or the gear button) with a searchable theme picker showing live color swatches for every bundled theme, appearance and terminal preferences, and an Explorer-integration toggle — all persisted to the config file with comments preserved and applied live on Save.
- Optional "Open in Paramux" entry in the Explorer right-click menu for folders and drives (per-user registry, no admin).
- Clickable pane sidebar with title, working directory, git branch/dirty state, listening ports, and a consistent attention color.
- Four agent states: working, waiting, done, and error. The same color appears in the sidebar, tab strip, and pane ring.
- Windows toast notifications and taskbar attention for agent events.
- Screen-reader support: Narrator/NVDA read pane text (screen and scrollback) with line, word, and page navigation, live re-reads on agent attention changes, and wide-glyph-accurate highlights.
- Hooks and fallbacks for Claude Code, Codex CLI, Gemini CLI, and OpenCode.
- Local control surface for listing windows, splitting panes, reading pane output, and setting notifications. Sensitive calls use a per-instance token; docs/paramux/fleet-cli.md maps every verb.
- Rebindable Ghostty-style configuration plus Ghostty and Windows Terminal theme import.
- Portable packaging with
paramux.exe, the console-friendlyparamux.comlauncher, and an idempotent user-PATH installer. - CLI lifecycle management:
paramux install,uninstall [--purge], and checksum-verified in-placeupdatefrom GitHub releases.
The current build is a public, unsigned prerelease. Signed installers, WinGet, and Scoop distribution are not published yet; the portable build is the truthful install path today.
The current test build is
v0.1.19,
published 2026-07-21 for Windows x64 and ARM64:
paramux-0.1.19-windows-x64-portable.zipSHA256SUMS-windows-x64.txtparamux-0.1.19-windows-arm64-portable.zipSHA256SUMS-windows-arm64.txt
This build is the completeness release: the last composed labels
localize. Layout-slot submenu labels and the activity timeline
now build from strings-table pieces — relative time composes
prefix+value+suffix so German leads with "vor" where English trails
with "ago", and the WORKING/WAITING/DONE/ERROR display words
localize while wire tags stay fixed. The runtime German smoke is
a permanent script (scripts/smoke-de.ps1) and joins the
pre-release sweep, now a quintet. The locale policy is written
down: a locale is one struct literal plus one setLocale arm,
compiled in. It builds on v0.1.18's resilience. Releases from
v0.1.0-paramux.7 onward apply with paramux update
(v0.1.0-paramux.4 remains a legacy test artifact).
- Download both the portable ZIP and
SHA256SUMS-windows-x64.txt. - Before extracting or running anything, compare the ZIP's digest with the release checksum:
Get-FileHash .\paramux-0.1.19-windows-x64-portable.zip -Algorithm SHA256
Get-Content .\SHA256SUMS-windows-x64.txtStop if the hashes do not match. 3. Extract the verified ZIP. Because this prerelease is unsigned, optionally confirm that status before running it:
Get-AuthenticodeSignature .\paramux\paramux.exe |
Select-Object Status, StatusMessage, SignerCertificate- Double-click
install-paramux.cmdinside the extractedparamuxfolder. It adds that folder to your userPATHand clears the downloaded-file mark. - Open a new PowerShell or Command Prompt window and run:
paramuxThe CLI can manage its own lifecycle from there on:
paramux update --check # is a newer release available?
paramux update # checksum-verified in-place update
paramux uninstall # remove PATH/PARAMUX_HOME/Explorer entries
paramux uninstall --purge # ... and delete %LOCALAPPDATA%\paramux
paramux install # re-wire a moved folder (same as install-paramux.cmd)To undo the PATH change with the script instead:
.\install-paramux.ps1 -RemoveThe prerelease is unsigned, so Explorer may show a SmartScreen warning. A GPU and driver exposing OpenGL 4.3 or newer are required; the portable ZIP does not bundle a software renderer.
The visible title-bar controls are intentionally enough to get started:
+opens a workspace.- The two split buttons next to
+create a pane to the right or below (hover any button for its shortcut). - The gear opens Settings — pick a theme from the searchable swatch list, and Save applies it live.
▾opens profiles, split directions, search, the command palette, and other workspace actions.- Click any row in the left sidebar to focus that pane; drag a row onto a pane to rearrange (edges dock, the middle swaps).
- Drag the gutter between panes to resize them.
- Right-click a terminal or a sidebar row for copy/paste, search, splits, zoom, merge, and new-window actions.
Useful defaults:
| Action | Binding |
|---|---|
| New workspace | Ctrl+Shift+T |
| Split right / down | Ctrl+Shift+O / Ctrl+Shift+E |
| Focus previous / next pane | Ctrl+Alt+[ / Ctrl+Alt+] |
| Recent workspace / pane (toggle) | Ctrl+Alt+L / Ctrl+Alt+; |
| Jump to newest agent notification | Ctrl+Alt+U |
| Attention inbox | Ctrl+Alt+I |
| Find in all panes | Ctrl+Alt+F |
| Attention digest | Ctrl+Alt+D |
| Health HUD | Ctrl+Alt+H |
| Always on top | Ctrl+Alt+T |
| Undo (close pane/workspace) | Ctrl+Shift+Z |
| Resize focused pane | Ctrl+Alt+Shift+Arrow |
| Next / previous workspace | Ctrl+Tab / Ctrl+Shift+Tab |
| Command palette | Ctrl+Shift+P |
| Find in scrollback | Ctrl+Shift+F |
| Copy / paste | Ctrl+Shift+C / Ctrl+Shift+V |
| Reload config | Ctrl+Shift+, |
See the effective keymap at any time:
paramux list-keybindsParamux injects PARAMUX_SURFACE_ID and PARAMUX_TOKEN into every pane so an
agent hook can address its own pane without guessing which window is active.
The included examples live in contrib/paramux/hooks/.
Manual smoke test from inside a pane:
paramux notify --state=waiting "Waiting for approval"
paramux notify --state=done "Task complete"
paramux notify --state=error "Tests failed"Supported states are working, waiting, done, and error. Plain
paramux notify "message" notifications default to waiting.
The control surface is local-only and uses Paramux's existing named-pipe
transport. Discovery is read-only; pane output and mutating actions require the
per-instance token written under %LOCALAPPDATA%\paramux.
# Discover window, tab, and pane IDs.
paramux list-windows
# Split the focused pane.
paramux perform-action new_split:right
# Read the focused pane, or target an ID returned above.
paramux read-pane
paramux read-pane --surface-id=42
# Send exact text and a terminal key to a pane.
paramux send --surface-id=42 "npm test"
paramux send-key --surface-id=42 enter
# Target an agent-attention event explicitly.
paramux notify --surface-id=42 --state=waiting "Review needed"The JSON discovery schema is paramux.windows.v2. Dedicated send and
send-key calls are bounded, UTF-8 validated, pane-targeted, and token-gated.
The generic perform-action allowlist still rejects terminal-write, file
helper, and crash actions.
Paramux creates its user configuration at:
%LOCALAPPDATA%\paramux\config.ghostty
The .ghostty extension and share/ghostty resources are retained for
compatibility with Ghostty's mature configuration and theme ecosystem.
font-family = JetBrains Mono
font-size = 12
theme = Draculaparamux show-config --default --docs | more
paramux list-themes
paramux import-theme "$env:LOCALAPPDATA\Packages\Microsoft.WindowsTerminal_8wekyb3d8bbwe\LocalState\settings.json"Requirements:
- Windows 10 or 11
- Zig 0.15.2 or another supported Zig 0.15 patch release
- Visual Studio 2022 with the C++ workload and Windows SDK
- Git for Windows
powershell -ExecutionPolicy Bypass -File scripts/fetch-zig-deps.ps1
zig build -Demit-exe=true
zig build test -Dtest-filter=<targeted-test-name>Build outputs:
zig-out\bin\paramux.exe
zig-out\bin\paramux.com
The shared Zig core lives under src/; the native application runtime is
src/apprt/win32.zig; packaging lives under dist/windows/ and
scripts/package-windows.ps1.
The source-of-truth scope and acceptance criteria are in
docs/paramux/paramux-prd.md. Paramux is moving
toward practical capability parity with cmux, tmux, and wmux while preserving a
native Windows feel. Compatibility means equivalent workflows where they make
sense on Windows—not blindly copying another product's UI or Unix-only internals.
The current source-backed matrix and gap order live in
docs/paramux/capability-parity.md.
Current priorities are:
- Finish every user-facing Paramux identity surface and package verifier.
- Make pane, tab, workspace, and attention workflows self-explanatory.
- Close the remaining source-backed cmux/tmux/wmux workflow gaps.
- Validate performance and interaction quality on real Windows GPUs.
- Ship signed installer, WinGet, Scoop, x64, and ARM64 release paths.
Paramux does not send analytics. Crash dumps stay local under
%LOCALAPPDATA%\paramux\crash and may contain terminal or process memory, so
review them before sharing. The built-in updater is the only normal outbound
network path and talks to the Paramux GitHub releases API when enabled.
Please report security issues according to SECURITY.md. Do not include tokens, private terminal output, or crash-memory contents in public reports.
Paramux is MIT licensed. Ghostty's shared terminal core and the native Windows work inherited from Winghostty remain under the same license; see LICENSE and the Git history for attribution.