WinCompose

WinCompose adds a compose key to Windows: press the compose key, then a short sequence, and you get a character your keyboard has no key for — Compose ' e gives é, Compose < 3 gives ❤.

PolyKybd uses it for unicode and emoji input on Windows. PolyKybdHost detects a running WinCompose and switches the keyboard into its compose mode automatically; without it, Windows unicode input falls back to a numeric escape that cannot produce emoji.

Why PolyKybd maintains a fork

WinCompose was written by Sam Hocevar, who has maintained it since 2013. That original project is no longer actively developed — its own issue tracker carries a notice to that effect, and the last release predates Windows 11’s taskbar changes.

Because unicode input on Windows is a hard dependency for PolyKybd, we maintain a fork so the tool keeps working for PolyKybd users. It is a fork, not a replacement: essentially all of the code, all of the compose sequence data, and the design are Sam’s work.

Note

The PolyKybd fork exists to keep a dependency healthy. If the original project becomes active again, our changes are intended to go back upstream.

What the PolyKybd fork changes

The fork builds on ell1010’s fork, which had already modernised the UI and retargeted the project to .NET Framework 4.8.1. On top of that we fixed:

• The tray tooltip never updated. A change notification was raised under the wrong property name, so the tooltip silently stayed empty.
• The tray icon stopped reflecting state. The composing indicator and the update marker had been dropped from the icon update path, and the “hide icon” setting did nothing at all.
• Settings dialog styling. Text and controls were sized well above native Windows dialogs, tabs wrapped onto a second row, and the window could not be resized or scrolled.
• The update check no longer polls the original project’s server over plain HTTP for versions that do not correspond to this fork’s builds.

Installing

The easiest route is from PolyKybdHost itself: while WinCompose is not running, the tray menu shows Install WinCompose…, which downloads the latest build and starts its installer for you. See Using the Tray App.

To install it by hand instead, download the latest build from the releases page.

Both a portable build and an installer are published. The portable build runs from any folder; the installer registers WinCompose to start with Windows.

Caution

Our builds are not code-signed yet, so Windows SmartScreen will warn that the publisher is unrecognised. Choose More info → Run anyway if you are happy to proceed. Signing is planned, and is waiting on a registered business entity — the certificate has to be issued to one.

Verifying your download

Because the builds are unsigned, every release ships a SHA256SUMS.txt listing the SHA-256 of each asset, produced by the same build that made them. To check a download in PowerShell:

Get-FileHash .\WinCompose-NoInstall-<version>.zip -Algorithm SHA256

Compare the result with the matching line in SHA256SUMS.txt.

This proves the file is byte-for-byte what our CI produced — it does not prove who produced it, which is what a signature is for. Until the certificate is in place it is the strongest check available.

Once WinCompose is running, set PolyKybdHost’s unicode input mode to WinCompose (it is detected automatically) and the keyboard’s emoji and unicode layers will work.

Credits and licence

WinCompose is © Sam Hocevar and contributors, released under the WTFPL. The PolyKybd fork keeps that licence.

• Original project — Sam Hocevar
• ell1010’s fork — the UI and .NET modernisation
• PolyKybd fork — the builds linked above