diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..05b5a08
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,13 @@
+# Generated by windows/sync.sh — see windows/README.md
+windows/pkg/lmcp.lua
+windows/pkg/server.lua
+windows/pkg/json.lua
+
+# Bundled Lua + LuaSocket runtime for the Windows MSI; downloaded
+# separately, not in git.
+windows/pkg/lua/
+
+# Editor / OS noise
+*.swp
+*.swo
+.DS_Store
diff --git a/windows/README.md b/windows/README.md
new file mode 100644
index 0000000..f33092f
--- /dev/null
+++ b/windows/README.md
@@ -0,0 +1,41 @@
+# lmcp Windows MSI build
+
+This directory contains the WiX manifest and packaging files for the
+Windows MSI build of lmcp.
+
+## Workflow
+
+```sh
+# 1. Pull the Lua + LuaSocket runtime into pkg/lua/ (one-time, see below).
+# 2. Sync the lmcp .lua sources from the root of the repo:
+./sync.sh
+# 3. Bump windows/lmcp.wxs `Version="…"` to match the release tag.
+# 4. Invoke WiX:
+candle.exe lmcp.wxs
+light.exe lmcp.wixobj -o lmcp-1.x.y.msi
+```
+
+## What's tracked vs. generated
+
+- **Tracked** (edit in git):
+  - `lmcp.wxs` — WiX MSI manifest
+  - `sync.sh` — copies root .lua sources → `pkg/`
+  - `README.md` — this file
+  - `pkg/install_service.bat` — Windows service installer
+  - `pkg/start.bat` — manual launcher
+
+- **Generated / external** (gitignored):
+  - `pkg/lmcp.lua`, `pkg/server.lua`, `pkg/json.lua` — produced by
+    `sync.sh`. Never edit directly; edit the root files and re-sync.
+  - `pkg/lua/` — the Lua + LuaSocket runtime drop-in. Download
+    separately and place here. Suggested source: the lua-binaries
+    project (https://github.com/rjpcomputing/luaforwindows) or a
+    similar pre-built bundle. The MSI expects `pkg/lua/lua.exe`,
+    `pkg/lua/lua54.dll`, and the `pkg/lua/socket/` + `pkg/lua/mime/`
+    subdirectories per the manifest.
+
+## Issue history
+
+Issue #18 (closed in v1.1.0) introduced this workflow after the
+`pkg/` lua sources had silently drifted ~6 months out of date,
+missing every feature added since April 2026.
diff --git a/windows/lmcp.wxs b/windows/lmcp.wxs
new file mode 100644
index 0000000..f446613
--- /dev/null
+++ b/windows/lmcp.wxs
@@ -0,0 +1,119 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
+  <!-- Bump Version on every release. See windows/README.md. -->
+  <Product Id="*"
+           Name="lmcp — Lua MCP Server"
+           Language="1033"
+           Version="1.1.0"
+           Manufacturer="QAP'LA Project"
+           UpgradeCode="A7F3E2D1-4B5C-6D7E-8F9A-0B1C2D3E4F5A">
+
+    <Package InstallerVersion="200"
+             Compressed="yes"
+             InstallScope="perMachine"
+             Description="Lightweight MCP server in Lua. 2MB RSS."
+             Comments="Zero-dependency MCP server." />
+
+    <MediaTemplate EmbedCab="yes" />
+
+    <MajorUpgrade DowngradeErrorMessage="A newer version is already installed." />
+
+    <Directory Id="TARGETDIR" Name="SourceDir">
+      <Directory Id="ProgramFiles64Folder">
+        <Directory Id="INSTALLFOLDER" Name="lmcp">
+          <Directory Id="LUA_DIR" Name="lua">
+            <Directory Id="SOCKET_DIR" Name="socket" />
+            <Directory Id="MIME_DIR" Name="mime" />
+          </Directory>
+        </Directory>
+      </Directory>
+    </Directory>
+
+    <!-- lmcp application files -->
+    <DirectoryRef Id="INSTALLFOLDER">
+      <Component Id="JsonLua" Guid="B1A2C3D4-E5F6-7890-ABCD-EF1234567890">
+        <File Id="json.lua" Source="pkg\json.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="LmcpLua" Guid="B1A2C3D4-E5F6-7890-ABCD-EF1234567891">
+        <File Id="lmcp.lua" Source="pkg\lmcp.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="ServerLua" Guid="B1A2C3D4-E5F6-7890-ABCD-EF1234567892">
+        <File Id="server.lua" Source="pkg\server.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="StartBat" Guid="B1A2C3D4-E5F6-7890-ABCD-EF1234567893">
+        <File Id="start.bat" Source="pkg\start.bat" KeyPath="yes" />
+      </Component>
+      <Component Id="InstallService" Guid="B1A2C3D4-E5F6-7890-ABCD-EF1234567894">
+        <File Id="install_service.bat" Source="pkg\install_service.bat" KeyPath="yes" />
+      </Component>
+    </DirectoryRef>
+
+    <!-- Lua runtime -->
+    <DirectoryRef Id="LUA_DIR">
+      <Component Id="LuaExe" Guid="C2B3D4E5-F6A7-8901-BCDE-F12345678900">
+        <File Id="lua.exe" Source="pkg\lua\lua.exe" KeyPath="yes" />
+      </Component>
+      <Component Id="LuaDll" Guid="C2B3D4E5-F6A7-8901-BCDE-F12345678901">
+        <File Id="lua54.dll" Source="pkg\lua\lua54.dll" KeyPath="yes" />
+      </Component>
+      <Component Id="SocketLua" Guid="C2B3D4E5-F6A7-8901-BCDE-F12345678902">
+        <File Id="socket.lua" Source="pkg\lua\socket.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="MimeLua" Guid="C2B3D4E5-F6A7-8901-BCDE-F12345678903">
+        <File Id="mime.lua" Source="pkg\lua\mime.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="Ltn12Lua" Guid="C2B3D4E5-F6A7-8901-BCDE-F12345678904">
+        <File Id="ltn12.lua" Source="pkg\lua\ltn12.lua" KeyPath="yes" />
+      </Component>
+    </DirectoryRef>
+
+    <!-- LuaSocket native DLLs -->
+    <DirectoryRef Id="SOCKET_DIR">
+      <Component Id="SocketCoreDll" Guid="D3C4E5F6-A7B8-9012-CDEF-123456789010">
+        <File Id="socket_core.dll" Name="core.dll" Source="pkg\lua\socket\core.dll" KeyPath="yes" />
+      </Component>
+      <Component Id="SocketFtp" Guid="D3C4E5F6-A7B8-9012-CDEF-123456789011">
+        <File Id="ftp.lua" Source="pkg\lua\socket\ftp.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="SocketHeaders" Guid="D3C4E5F6-A7B8-9012-CDEF-123456789012">
+        <File Id="headers.lua" Source="pkg\lua\socket\headers.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="SocketHttp" Guid="D3C4E5F6-A7B8-9012-CDEF-123456789013">
+        <File Id="http.lua" Source="pkg\lua\socket\http.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="SocketTp" Guid="D3C4E5F6-A7B8-9012-CDEF-123456789014">
+        <File Id="tp.lua" Source="pkg\lua\socket\tp.lua" KeyPath="yes" />
+      </Component>
+      <Component Id="SocketUrl" Guid="D3C4E5F6-A7B8-9012-CDEF-123456789015">
+        <File Id="url.lua" Source="pkg\lua\socket\url.lua" KeyPath="yes" />
+      </Component>
+    </DirectoryRef>
+
+    <DirectoryRef Id="MIME_DIR">
+      <Component Id="MimeCoreDll" Guid="E4D5F6A7-B8C9-0123-DEFA-234567890120">
+        <File Id="mime_core.dll" Name="core.dll" Source="pkg\lua\mime\core.dll" KeyPath="yes" />
+      </Component>
+    </DirectoryRef>
+
+    <Feature Id="MainFeature" Title="lmcp Server" Level="1">
+      <ComponentRef Id="JsonLua" />
+      <ComponentRef Id="LmcpLua" />
+      <ComponentRef Id="ServerLua" />
+      <ComponentRef Id="StartBat" />
+      <ComponentRef Id="InstallService" />
+      <ComponentRef Id="LuaExe" />
+      <ComponentRef Id="LuaDll" />
+      <ComponentRef Id="SocketLua" />
+      <ComponentRef Id="MimeLua" />
+      <ComponentRef Id="Ltn12Lua" />
+      <ComponentRef Id="SocketCoreDll" />
+      <ComponentRef Id="SocketFtp" />
+      <ComponentRef Id="SocketHeaders" />
+      <ComponentRef Id="SocketHttp" />
+      <ComponentRef Id="SocketTp" />
+      <ComponentRef Id="SocketUrl" />
+      <ComponentRef Id="MimeCoreDll" />
+    </Feature>
+
+  </Product>
+</Wix>
diff --git a/windows/pkg/install_service.bat b/windows/pkg/install_service.bat
new file mode 100644
index 0000000..afe222a
--- /dev/null
+++ b/windows/pkg/install_service.bat
@@ -0,0 +1,24 @@
+@echo off
+REM Install lmcp as a Windows service using NSSM (Non-Sucking Service Manager)
+REM Download nssm from https://nssm.cc if not present
+
+if not exist "%~dp0nssm.exe" (
+    echo ERROR: nssm.exe not found in %~dp0
+    echo Download from https://nssm.cc and place nssm.exe here.
+    exit /b 1
+)
+
+set INSTALL_DIR=%~dp0
+set SERVICE_NAME=lmcp
+
+echo Installing lmcp as Windows service...
+%INSTALL_DIR%nssm.exe install %SERVICE_NAME% "%INSTALL_DIR%lua\lua.exe" "%INSTALL_DIR%server.lua"
+%INSTALL_DIR%nssm.exe set %SERVICE_NAME% AppDirectory "%INSTALL_DIR%"
+%INSTALL_DIR%nssm.exe set %SERVICE_NAME% AppEnvironmentExtra "LMCP_PORT=8080"
+%INSTALL_DIR%nssm.exe set %SERVICE_NAME% DisplayName "lmcp MCP Server"
+%INSTALL_DIR%nssm.exe set %SERVICE_NAME% Description "Lightweight MCP server in Lua"
+%INSTALL_DIR%nssm.exe set %SERVICE_NAME% Start SERVICE_AUTO_START
+%INSTALL_DIR%nssm.exe start %SERVICE_NAME%
+
+echo Done. Service '%SERVICE_NAME%' installed and started.
+echo Check: sc query %SERVICE_NAME%
diff --git a/windows/pkg/start.bat b/windows/pkg/start.bat
new file mode 100644
index 0000000..4c09d34
--- /dev/null
+++ b/windows/pkg/start.bat
@@ -0,0 +1,7 @@
+@echo off
+REM lmcp — Lua MCP Server
+REM Start the server on port 8080 (or LMCP_PORT if set)
+cd /d "%~dp0"
+if not defined LMCP_PORT set LMCP_PORT=8080
+echo Starting lmcp on port %LMCP_PORT%...
+lua\lua.exe server.lua
diff --git a/windows/sync.sh b/windows/sync.sh
new file mode 100755
index 0000000..45f6f63
--- /dev/null
+++ b/windows/sync.sh
@@ -0,0 +1,25 @@
+#!/bin/sh
+# windows/sync.sh — refresh windows/pkg/ from root .lua sources (issue #18).
+#
+# Run BEFORE invoking the WiX build so the MSI bundles whatever is in
+# master. The .lua files in windows/pkg/ are regenerated on every run
+# and are gitignored — never edit them directly.
+#
+# Idempotent: re-running just re-copies. Safe to call from a Makefile,
+# a CI step, or by hand before `candle.exe + light.exe`.
+
+set -eu
+
+here=$(dirname "$(readlink -f "$0")")
+root=$(cd "$here/.." && pwd)
+
+for f in lmcp.lua server.lua json.lua; do
+    if [ ! -f "$root/$f" ]; then
+        echo "windows/sync.sh: missing source $root/$f" >&2
+        exit 1
+    fi
+    cp "$root/$f" "$here/pkg/$f"
+    echo "  synced $f"
+done
+
+echo "windows/sync.sh: done — pkg/ matches root .lua at $(date +%Y-%m-%dT%H:%M:%S)"