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+# Microsoft Word for Windows 1.1a - Native x64 Port
+
+This project is a fully working native Windows x64 port of Microsoft Word for
+Windows 1.1a, whose historical codename was **Opus**. It builds the original
+Word source and resources together with modern replacements for the 16-bit
+assembly, segmented-memory, and Win16 platform boundaries.
+
+The result is the original Word application and user experience running as a
+64-bit Windows executable. This is not an emulator or a reimplementation using
+a modern editor control.
+
+## Requirements
+
+- 64-bit Windows
+- Visual Studio 2022 with **Desktop development with C++**
+- A Windows 10 or Windows 11 SDK installed through Visual Studio
+- CMake 3.25 or newer
+- PowerShell
+
+## Build and run
+
+Clone the repository, configure the included CMake preset, and build it from a
+PowerShell prompt:
+
+```powershell
+git clone https://github.com/jmarshall23/msword.git
+Set-Location msword\src
+
+cmake --preset x64-debug
+cmake --build --preset x64-debug
+
+& ..\bin\WORD1.exe
+```
+
+For an optimized build, use the release preset instead:
+
+```powershell
+cmake --preset x64-release
+cmake --build --preset x64-release
+& ..\bin\WORD1.exe
+```
+
+The presets use the Visual Studio 2022 x64 generator. After configuration, the
+generated solution can also be opened directly from
+`out\MicrosoftWordX64Port.sln`; use `WORD1` as the startup project.
+
+## Test
+
+Run the complete Debug test suite from the repository root:
+
+```powershell
+ctest --test-dir .\out -C Debug --output-on-failure
+```
+
+Or, when your current directory is `src`:
+
+```powershell
+ctest --test-dir ..\out -C Debug --output-on-failure
+```
+
+For a release build, replace `Debug` with `Release`. The suite covers the
+ported x64 runtime, original Word data structures and command tables, process
+startup, and automated UI workflows including typing, selection, formatting,
+dialogs, and saving.
+
+## Project layout
+
+| Path | Purpose |
+| --- | --- |
+| `src/Opus/` | Original Microsoft Word/Opus application source and resources |
+| `src/OpusEtAl/` | Original supporting tools, libraries, and build inputs |
+| `src/OpusProg/` | Historical program documentation |
+| `src/port/original/` | x64 compatibility layer, translated routines, and tests |
+| `src/port/tools/` | Native replacements for historical build-time tools |
+| `src/cmake/` | Resource and source-generation helpers |
+| `out/` | CMake cache and generated Visual Studio solution |
+| `build/` | Intermediate tools, tests, probes, PDBs, and diagnostics |
+| `bin/` | Final executable and runtime files |
+
+`out`, `build`, and `bin` are generated locally during configuration and
+compilation.
+
+## How the port works
+
+The original C and resource files remain the authoritative implementation.
+The port adds only the platform work needed to build and run that code safely
+on 64-bit Windows:
+
+- 16-bit x86 assembly entry points are translated to fixed-width C or C++.
+- Segmented and double-indirect memory handles are mapped to an x64-safe native
+  runtime.
+- Win16-specific startup, messaging, graphics, file, and resource behavior is
+  adapted to current Win32 APIs.
+- Original command, dialog, cursor, bitmap, and other generated assets are
+  rebuilt by native host tools as part of the CMake graph.
+- Unit, runtime, smoke, and UI tests guard compatibility with the original
+  algorithms and application behavior.
+
+CMake inventories the legacy assembly tree but does not compile those modules
+into native targets. This keeps the historical implementation available as a
+reference while ensuring all shipped code is valid for AMD64.
+
+## Useful targets
+
+| Target | Description |
+| --- | --- |
+| `WORD1` | The native x64 Microsoft Word executable |
+| `opus_original_engine` | Original Word application engine compiled for x64 |
+| `opus_x64_runtime` | Native runtime and translated assembly behavior |
+| `opus_word1_ui_test` | Automated end-to-end UI test driver |
+| `legacy_sources` | IDE-visible reference collection of the original assembly |
+
+Build a specific target with:
+
+```powershell
+cmake --build --preset x64-debug --target WORD1
+```
+
+## Contributing
+
+Changes should preserve the original Word behavior while keeping all native
+interfaces pointer-width safe. Prefer source-equivalent translations of
+historical routines, isolate unavoidable Windows API adaptation at the port
+boundary, and add focused tests for newly translated behavior.
+
+## Copyright
+
+The historical source files retain their original Microsoft and third-party
+copyright notices. This repository does not currently include a top-level
+license file; review the applicable rights before redistributing the source or
+binaries.