diff --git a/.gitignore b/.gitignore
index 33d6544..f2bb995 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@ obj/
 /mmtty/
 /bridge/XMMT.ocx
 engine-probe.log
+/dist/
diff --git a/README.md b/README.md
index 7a4e01b..09d415b 100644
--- a/README.md
+++ b/README.md
@@ -40,6 +40,36 @@ Everything that judges a station — the bar under the callsign box, a row in th
 check window, a spot on the bandmap, a line in the log — is coloured by the same
 scorer: red for a dupe, green for a new multiplier, blue for points.
 
+## Windows
+
+Build the Windows copy on any machine that has the .NET 10 SDK:
+
+```sh
+./publish-windows.sh        # writes dist/nonemm-win-x64/ and dist/nonemm-win-x64.zip
+```
+
+On Windows itself, run this from PowerShell instead:
+
+```powershell
+dotnet publish src\Nonemm.App -c Release -r win-x64 --self-contained -o dist\nonemm-win-x64
+```
+
+The result needs no .NET install. Unzip it anywhere you can write to and run
+`Nonemm.App.exe`. Files go in `Documents\N1MM Logger+` and `Documents\Nonemm`,
+or in the folder `NONEMM_HOME` names.
+
+What differs from Linux:
+
+| Part | On Windows |
+| --- | --- |
+| MMTTY and 2Tone | The bridge starts directly, with no Wine. Register `bridge\XMMT.ocx` once with the **Register** button in the digital settings. Windows asks for administrator rights, because the control is written to the registry. Keep the file where it is afterwards. See `docs/digital-bridge.md` |
+| CW | `cwdaemon` has no Windows build. Use a WinKeyer on its COM port |
+| Radio | Start `rigctld` from the Windows hamlib build, with a COM port: `rigctld -m 2028 -r COM3` |
+| Voice playback | Plays through PowerShell's `Media.SoundPlayer`. The command is a setting |
+| Voice recording | Windows has no recorder to call. Install `sox` or `ffmpeg` and put its command in the keyer settings |
+
+No part of this has been run on Windows yet. The tests pass on Linux only.
+
 ## What it does
 
 | | |
@@ -56,13 +86,13 @@ scorer: red for a dupe, green for a new multiplier, blue for points.
 | Bandmap | drawn like N1MM's: a frequency scale with the receiver on it and callsigns beside it, joined by leader lines |
 | Network | contacts shared with the other stations of a multi-operator entry, in N1MM's own contact message |
 | Keying | CW through `cwdaemon` or a WinKeyer, with N1MM's message macros; phone through the voice keyer, which plays each operator's own recordings |
-| Digital | N1MM's digital interface window, running MMTTY or 2Tone under Wine through the same `XMMT.ocx` N1MM drives them with |
+| Digital | N1MM's digital interface window, running MMTTY or 2Tone (under Wine on Linux, directly on Windows) through the same `XMMT.ocx` N1MM drives them with |
 
 ### The digital window
 
 **Window ▸ Digital Interface** opens N1MM's digital interface. **Engine ▸
-Settings** says where MMTTY or 2Tone is; **Engine ▸ Start** runs it under Wine.
-`docs/digital-bridge.md` covers setting the Wine prefix up.
+Settings** says where MMTTY or 2Tone is; **Engine ▸ Start** runs it: under Wine on Linux, directly on Windows.
+`docs/digital-bridge.md` covers setting up the Wine prefix or, on Windows, registering the control.
 
 What the window does, and what each part of it is for:
 
@@ -1040,7 +1070,7 @@ windows redraw where they stand.
 | `Nonemm.Spotting` | Spots, the bandmap, the DX cluster client |
 | `Nonemm.Network` | Contacts shared between the stations of a multi-operator entry |
 | `Nonemm.Keying` | CW through `cwdaemon` or a WinKeyer, and the voice keyer's recordings |
-| `Nonemm.Digital` | MMTTY and 2Tone, over the Wine bridge in `bridge/` |
+| `Nonemm.Digital` | MMTTY and 2Tone, over the bridge in `bridge/` |
 | `Nonemm.Session` | The contest in progress, and one entry position per radio — no UI toolkit |
 | `Nonemm.App` | The Avalonia windows |
 
diff --git a/docs/digital-bridge.md b/docs/digital-bridge.md
index bbb7e3c..9ce1be5 100644
--- a/docs/digital-bridge.md
+++ b/docs/digital-bridge.md
@@ -1,9 +1,9 @@
-# MMTTY and 2Tone through Wine
+# MMTTY and 2Tone through the bridge
 
 MMTTY is a Windows program with no socket, pipe or file interface. N1MM does not
 talk to it directly either: it hosts `XMMT.ocx`, a 32-bit ActiveX control that
 starts `MMTTY.EXE` and exchanges window messages with it. A Linux process cannot
-load that control, so Nonemm runs a small Windows program under Wine —
+load that control, so Nonemm runs a small Windows program (under Wine on Linux) —
 `bridge/nonemm-mmtty-bridge.exe` — which hosts the control and passes lines over
 its standard input and output.
 
@@ -98,7 +98,25 @@ Three things cost a day between them, so they are written down:
   message, closes the engine's windows, and kills the process if it is still
   there five seconds later.
 
-## Setting it up
+## Setting it up on Windows
+
+There is no Wine. `ProcessBridgeChannel` starts `nonemm-mmtty-bridge.exe`
+directly, and the engine path goes to the bridge as it is.
+
+The control must be registered once. The Register button in Config > Digital
+does it with `WindowsControlSetup`, which runs the 32-bit `regsvr32` (the one in
+`SysWOW64` on 64-bit Windows) on `XMMT.ocx` in place. Windows shows the
+administrator prompt, because registering writes to `HKEY_CLASSES_ROOT`. The same
+by hand, from an administrator prompt:
+
+```bat
+%WINDIR%\SysWOW64\regsvr32.exe bridge\XMMT.ocx
+```
+
+Do not move `XMMT.ocx` after that, or register it again. Nothing in this path
+has been run on Windows.
+
+## Setting it up under Wine
 
 Config > Digital has a Register button. It does what the next paragraph
 describes, in the prefix named in the same dialog, and writes the result under
diff --git a/publish-windows.sh b/publish-windows.sh
new file mode 100755
index 0000000..24b56e6
--- /dev/null
+++ b/publish-windows.sh
@@ -0,0 +1,15 @@
+#!/bin/sh
+# Builds a self-contained Windows x64 copy in dist/nonemm-win-x64 and zips it.
+# The target machine needs no .NET install. Pass another runtime id as the
+# first argument, for example win-arm64 (the bridge and XMMT.ocx are 32 bit
+# x86 either way).
+rid="${1:-win-x64}"
+cd "$(dirname "$0")" || exit 1
+out="dist/nonemm-$rid"
+rm -rf "$out"
+./build.sh publish src/Nonemm.App -c Release -r "$rid" --self-contained -o "$out" || exit 1
+rm -f "$out"/*.pdb
+rm -f "dist/nonemm-$rid.zip"
+python3 -c 'import shutil, sys; shutil.make_archive(sys.argv[1], "zip", "dist", sys.argv[2])' \
+    "dist/nonemm-$rid" "nonemm-$rid" || exit 1
+echo "dist/nonemm-$rid.zip"
diff --git a/src/Nonemm.App/AppSession.cs b/src/Nonemm.App/AppSession.cs
index 2fa1330..94d523f 100644
--- a/src/Nonemm.App/AppSession.cs
+++ b/src/Nonemm.App/AppSession.cs
@@ -699,10 +699,12 @@ public sealed class AppSession : IDisposable
             OnTop = Settings.DigitalEngineOnTop,
             PttPort = Settings.DigitalPttPort.Trim().Length > 0 ? Settings.DigitalPttPort : null,
         };
-        WineBridgeChannel channel = new(
+        ProcessBridgeChannel channel = new(
             Settings.DigitalBridgePath,
             Settings.DigitalWinePrefix.Trim().Length > 0 ? Settings.DigitalWinePrefix : null,
-            Settings.DigitalWineCommand.Trim().Length > 0 ? Settings.DigitalWineCommand : "wine",
+            OperatingSystem.IsWindows()
+                ? null
+                : Settings.DigitalWineCommand.Trim().Length > 0 ? Settings.DigitalWineCommand : "wine",
             Paths.Diagnostics);
         MmttyEngine started = new(channel, options);
         await started.StartAsync();
diff --git a/src/Nonemm.App/Dialogs/DigitalDialog.axaml b/src/Nonemm.App/Dialogs/DigitalDialog.axaml
index 0d4cc05..081754e 100644
--- a/src/Nonemm.App/Dialogs/DigitalDialog.axaml
+++ b/src/Nonemm.App/Dialogs/DigitalDialog.axaml
@@ -124,7 +124,7 @@
       <TabItem Header="Engine">
         <ScrollViewer>
           <StackPanel Margin="4,8,10,4">
-            <TextBlock TextWrapping="Wrap" FontSize="11" Opacity="0.75"
+            <TextBlock Name="EngineNote" TextWrapping="Wrap" FontSize="11" Opacity="0.75"
                        Text="MMTTY and 2Tone are Windows programs. They run under Wine, driven through the same XMMT.ocx control N1MM uses, with a small bridge program in between. See docs/digital-bridge.md for setting the Wine prefix up." />
             <TextBlock Classes="label" Text="Engine program (mmtty.exe or 2Tone.exe)" />
             <Grid ColumnDefinitions="*,6,Auto">
@@ -136,13 +136,13 @@
               <TextBox Name="BridgeBox" />
               <Button Grid.Column="2" Content="Browse…" Click="OnBrowseBridge" />
             </Grid>
-            <Grid ColumnDefinitions="*,8,160" RowDefinitions="Auto,Auto">
+            <Grid Name="WineRow" ColumnDefinitions="*,8,160" RowDefinitions="Auto,Auto">
               <TextBlock Classes="label" Text="Wine prefix (empty for Wine's own)" />
               <TextBox Name="PrefixBox" Grid.Row="1" />
               <TextBlock Grid.Column="2" Classes="label" Text="Wine command" />
               <TextBox Name="WineBox" Grid.Row="1" Grid.Column="2" />
             </Grid>
-            <TextBlock Classes="label" Text="Control (XMMT.ocx), registered in the prefix above" />
+            <TextBlock Name="ControlLabel" Classes="label" Text="Control (XMMT.ocx), registered in the prefix above" />
             <Grid ColumnDefinitions="*,6,Auto,6,Auto">
               <TextBox Name="ControlBox" />
               <Button Grid.Column="2" Content="Browse…" Click="OnBrowseControl" />
diff --git a/src/Nonemm.App/Dialogs/DigitalDialog.axaml.cs b/src/Nonemm.App/Dialogs/DigitalDialog.axaml.cs
index ab29993..d7b4124 100644
--- a/src/Nonemm.App/Dialogs/DigitalDialog.axaml.cs
+++ b/src/Nonemm.App/Dialogs/DigitalDialog.axaml.cs
@@ -106,6 +106,14 @@ public sealed partial class DigitalDialog : Window
         ControlBox.Text = settings.DigitalControlPath;
         PrefixBox.Text = settings.DigitalWinePrefix;
         WineBox.Text = settings.DigitalWineCommand;
+        if (OperatingSystem.IsWindows())
+        {
+            WineRow.IsVisible = false;
+            EngineNote.Text = "MMTTY and 2Tone are driven through the same XMMT.ocx control N1MM uses, "
+                + "with a small bridge program in between. Register the control once, before the first start. "
+                + "See docs/digital-bridge.md.";
+            ControlLabel.Text = "Control (XMMT.ocx), registered where it is. Keep the file there";
+        }
         PttBox.Text = settings.DigitalPttPort;
     }
 
@@ -251,12 +259,20 @@ public sealed partial class DigitalDialog : Window
     {
         RegisterButton.IsEnabled = false;
         Say("Registering…");
-        WinePrefixSetup setup = new(
-            PrefixBox.Text?.Trim() is { Length: > 0 } prefix ? prefix : null,
-            WineBox.Text?.Trim() is { Length: > 0 } wine ? wine : "wine");
+        string control = ControlBox.Text?.Trim() ?? "";
         try
         {
-            Say(await setup.RegisterAsync(ControlBox.Text?.Trim() ?? ""));
+            if (OperatingSystem.IsWindows())
+            {
+                Say(await new WindowsControlSetup().RegisterAsync(control));
+            }
+            else
+            {
+                WinePrefixSetup setup = new(
+                    PrefixBox.Text?.Trim() is { Length: > 0 } prefix ? prefix : null,
+                    WineBox.Text?.Trim() is { Length: > 0 } wine ? wine : "wine");
+                Say(await setup.RegisterAsync(control));
+            }
         }
         catch (Exception failure) when (failure is IOException or InvalidOperationException)
         {
diff --git a/src/Nonemm.Digital/WineBridgeChannel.cs b/src/Nonemm.Digital/ProcessBridgeChannel.cs
similarity index 88%
rename from src/Nonemm.Digital/WineBridgeChannel.cs
rename to src/Nonemm.Digital/ProcessBridgeChannel.cs
index 83deb22..50f0a3e 100644
--- a/src/Nonemm.Digital/WineBridgeChannel.cs
+++ b/src/Nonemm.Digital/ProcessBridgeChannel.cs
@@ -2,14 +2,15 @@ using System.Diagnostics;
 
 namespace Nonemm.Digital;
 
-/// Runs the bridge under Wine and talks to it over its standard input and
-/// output. Wine writes its own diagnostics to standard error, so the protocol
-/// has standard output to itself.
-public sealed class WineBridgeChannel : BridgeChannel
+/// Runs the bridge and talks to it over its standard input and output. On
+/// Linux the bridge runs under Wine, which writes its own diagnostics to
+/// standard error, so the protocol has standard output to itself. On Windows
+/// `wine` is null and the bridge is started directly.
+public sealed class ProcessBridgeChannel : BridgeChannel
 {
     private const int KeptErrorLines = 20;
 
-    private readonly string wine;
+    private readonly string? wine;
     private readonly string bridgePath;
     private readonly string? prefix;
     private readonly string? logFolder;
@@ -22,12 +23,13 @@ public sealed class WineBridgeChannel : BridgeChannel
     private int lastCount = int.MinValue;
 
     /// `prefix` is the WINEPREFIX to run in. Left null, Wine uses its default,
-    /// which is what a station with one prefix wants. `logFolder`, when it is
+    /// which is what a station with one prefix wants. `wine` is the Wine
+    /// command, or null to run the bridge without Wine. `logFolder`, when it is
     /// given, is where the protocol log for this run is written.
-    public WineBridgeChannel(
+    public ProcessBridgeChannel(
         string bridgePath,
         string? prefix = null,
-        string wine = "wine",
+        string? wine = "wine",
         string? logFolder = null)
     {
         this.bridgePath = bridgePath;
@@ -70,6 +72,10 @@ public sealed class WineBridgeChannel : BridgeChannel
         string path,
         CancellationToken cancellation = default)
     {
+        if (wine is null)
+        {
+            return Path.GetFullPath(path);
+        }
         using Process winepath = Start("winepath", "-w", path);
         string converted = await winepath.StandardOutput.ReadToEndAsync(cancellation)
             .ConfigureAwait(false);
@@ -168,13 +174,17 @@ public sealed class WineBridgeChannel : BridgeChannel
     {
         ProcessStartInfo start = new()
         {
-            FileName = wine,
+            FileName = wine ?? program,
             RedirectStandardInput = true,
             RedirectStandardOutput = true,
             RedirectStandardError = true,
             UseShellExecute = false,
+            CreateNoWindow = true,
         };
-        start.ArgumentList.Add(program);
+        if (wine is not null)
+        {
+            start.ArgumentList.Add(program);
+        }
         foreach (string argument in arguments)
         {
             start.ArgumentList.Add(argument);
diff --git a/src/Nonemm.Digital/WindowsControlSetup.cs b/src/Nonemm.Digital/WindowsControlSetup.cs
new file mode 100644
index 0000000..7bbd5d7
--- /dev/null
+++ b/src/Nonemm.Digital/WindowsControlSetup.cs
@@ -0,0 +1,58 @@
+using System.Diagnostics;
+
+namespace Nonemm.Digital;
+
+/// Registers XMMT.ocx on Windows, which is what the bridge needs before it can
+/// create the control. The control is registered where it is, so the file must
+/// stay in place afterwards.
+public sealed class WindowsControlSetup
+{
+    /// The control is 32 bit. On 64-bit Windows the 32-bit regsvr32 is in
+    /// SysWOW64, and the one in System32 cannot load it.
+    public static string Regsvr32Path(string windowsFolder) =>
+        Directory.Exists(Path.Combine(windowsFolder, "SysWOW64"))
+            ? Path.Combine(windowsFolder, "SysWOW64", "regsvr32.exe")
+            : Path.Combine(windowsFolder, "System32", "regsvr32.exe");
+
+    /// Registers the control and returns what to show the operator. It writes
+    /// to HKEY_CLASSES_ROOT, so it runs elevated: Windows asks the operator to
+    /// allow that. It throws when the operator refuses or regsvr32 fails.
+    public async Task<string> RegisterAsync(
+        string controlPath,
+        CancellationToken cancellation = default)
+    {
+        if (!File.Exists(controlPath))
+        {
+            throw new FileNotFoundException($"{controlPath} is not there", controlPath);
+        }
+        string regsvr32 = Regsvr32Path(Environment.GetFolderPath(Environment.SpecialFolder.Windows));
+        ProcessStartInfo start = new()
+        {
+            FileName = regsvr32,
+            ArgumentList = { "/s", Path.GetFullPath(controlPath) },
+            UseShellExecute = true,
+            Verb = "runas",
+        };
+        Process running;
+        try
+        {
+            running = Process.Start(start)
+                ?? throw new InvalidOperationException($"{regsvr32} did not start");
+        }
+        catch (System.ComponentModel.Win32Exception refused)
+        {
+            throw new InvalidOperationException(
+                $"{regsvr32} did not start: {refused.Message}", refused);
+        }
+        using (running)
+        {
+            await running.WaitForExitAsync(cancellation).ConfigureAwait(false);
+            if (running.ExitCode != 0)
+            {
+                throw new InvalidOperationException(
+                    $"{regsvr32} /s {controlPath} failed with exit code {running.ExitCode}");
+            }
+        }
+        return $"{Path.GetFileName(controlPath)} registered";
+    }
+}
diff --git a/tests/Nonemm.Digital.Tests/WindowsControlSetupTests.cs b/tests/Nonemm.Digital.Tests/WindowsControlSetupTests.cs
new file mode 100644
index 0000000..5a77c12
--- /dev/null
+++ b/tests/Nonemm.Digital.Tests/WindowsControlSetupTests.cs
@@ -0,0 +1,34 @@
+using Nonemm.Digital;
+
+namespace Nonemm.Digital.Tests;
+
+public class WindowsControlSetupTests
+{
+    [Fact]
+    public void ASixtyFourBitWindowsRegistersWithTheCopyInSysWow64()
+    {
+        string windows = Directory.CreateTempSubdirectory().FullName;
+        Directory.CreateDirectory(Path.Combine(windows, "SysWOW64"));
+
+        Assert.Equal(
+            Path.Combine(windows, "SysWOW64", "regsvr32.exe"),
+            WindowsControlSetup.Regsvr32Path(windows));
+    }
+
+    [Fact]
+    public void AThirtyTwoBitWindowsRegistersWithTheCopyInSystem32()
+    {
+        string windows = Directory.CreateTempSubdirectory().FullName;
+
+        Assert.Equal(
+            Path.Combine(windows, "System32", "regsvr32.exe"),
+            WindowsControlSetup.Regsvr32Path(windows));
+    }
+
+    [Fact]
+    public async Task AControlThatIsNotThereIsSaidSo()
+    {
+        await Assert.ThrowsAsync<FileNotFoundException>(
+            () => new WindowsControlSetup().RegisterAsync("/nowhere/XMMT.ocx"));
+    }
+}
diff --git a/tools/Nonemm.EngineProbe/Program.cs b/tools/Nonemm.EngineProbe/Program.cs
index 0a20031..a619d9e 100644
--- a/tools/Nonemm.EngineProbe/Program.cs
+++ b/tools/Nonemm.EngineProbe/Program.cs
@@ -46,7 +46,7 @@ public static class Program
 
         using ProbeLog log = new(Option(options, "out", "engine-probe.log"));
         MmttyEngine engine = new(
-            new WineBridgeChannel(
+            new ProcessBridgeChannel(
                 Option(options, "bridge", Path.Combine("bridge", "nonemm-mmtty-bridge.exe")),
                 options.GetValueOrDefault("prefix"),
                 logFolder: options.GetValueOrDefault("log")),