diff --git a/README.md b/README.md
index 1275b02..861cd89 100644
--- a/README.md
+++ b/README.md
@@ -1,34 +1,71 @@
 ti84-ref_app
 ==================
 
-## Work in Progress
+<p align="center">
+    <a href="https://github.com/ckormanyos/ti84-ref_app/actions">
+        <img src="https://github.com/ckormanyos/ti84-ref_app/actions/workflows/ti84-ref_app.yml/badge.svg" alt="build"></a>
+    <a href="https://github.com/ckormanyos/ti84-ref_app/issues?q=is%3Aissue+is%3Aopen+sort%3Aupdated-desc">
+        <img src="https://custom-icon-badges.herokuapp.com/github/issues-raw/ckormanyos/ti84-ref_app?logo=github" alt="Issues" /></a>
+    <a href="https://github.com/ckormanyos/ti84-ref_app/blob/main/UNLICENSE">
+        <img src="https://img.shields.io/badge/license-The Unlicense-blue.svg" alt="The Unlicense"></a>
+</p>
 
-**Note** This repository is work in progress. The build system, file-naming and tool-poratability **all** need significant tuning. The basic stuff compiles and runs, but there are a lot of formalities to be done, including pics (images) and CI.
+`ckormanyos/ti84-ref_app` creates a fully functioning reference application for the z80-based TI84-Plus monochrome graphics calculator.
 
-## ti84-ref_app
-
-ckormanyos/ti84-ref_app creates a fully functioning reference application for the z80-based TI84-Plus monochrome graphics calculator.
-
-The reference application contains a small blinky application supported by a skinny `main()`
-subroutine written in high-level C (as opposed to assembly).
+The reference application implements a small _blinky_-application supported by a skinny `main()`
+subroutine written in high-level C (as opposed to assembly). Since there is no LED present
+on the calculator-target system, the text _ON_/_OFF_ is printed at row-$2$, column-$7$,
+_toggling_ between _ON_ and _OFF_ at a frequency of about ${\sim}\frac{1}{2}Hz$.
 
 This application has a complete C-runtime initialization based on and using the
 free [`sdcc`](https://sdcc.sourceforge.net) toolchain.
 
 ## Building
 
-TBD Supported on `Win*` and `*ninx`.
+The build system is supported on both `Win*` and `*nix`. Ported `*nix` tools
+support the `Win*`-build.
+
+### Build on `Win*`
+
+Prerequisites:
+  - Install sdcc version 4.3 or higher.
+  - Install python.
+
+```cmd
+cd ti84-ref_app\build
+make TYP_OS=WIN all
+```
+
+The build results including HEX-File and `refapp.8xp` will be built in the `bin`-directory.
+
+### Build on `*nix`
+
+Prerequisites:
+  - Install sdcc version 4.3 or higher.
+
+```cmd
+cd ti84-ref_app/build
+make TYP_OS=UNIX all
+```
+
+The build results including HEX-File and `refapp.8xp` will be built in the `bin`-directory.
 
 ## Testing and Continuous Integration
 
-TBD
+Testing has been performed on the target system, which is a fully-functioning
+TI84-Plus calculator purchased years ago from a commercial retailer.
+
+Continuous integration builds the application on an ubuntu-latest GHA runner
+and verifies the presence of `bin/refapp-8xp`.
 
 ## Images
 
-TBD
+TBD: Provide images of the _blinking_ text.
 
 ## Aditional Information
 
+Licensing TBD.
+
 This project has been inspired by and influenced by numerous previous works,
 including (but not limited to)
 the [azertyfun/LibTI](https://github.com/azertyfun/LibTI) project.
diff --git a/build/ti84-ref_app.vcxproj b/build/ti84-ref_app.vcxproj
index aae09a8..b05895a 100644
--- a/build/ti84-ref_app.vcxproj
+++ b/build/ti84-ref_app.vcxproj
@@ -11,6 +11,7 @@
   </ItemGroup>
   <ItemGroup>
     <None Include="..\.github\workflows\ti84-ref_app.yml" />
+    <None Include="..\README.md" />
     <None Include="..\src\crt0.s" />
     <None Include="Makefile" />
   </ItemGroup>
diff --git a/build/ti84-ref_app.vcxproj.filters b/build/ti84-ref_app.vcxproj.filters
index 15a9d4b..49945af 100644
--- a/build/ti84-ref_app.vcxproj.filters
+++ b/build/ti84-ref_app.vcxproj.filters
@@ -13,6 +13,9 @@
     <Filter Include=".github\workflows">
       <UniqueIdentifier>{51c0fac1-3039-46f7-b08f-aa19a9737be9}</UniqueIdentifier>
     </Filter>
+    <Filter Include="_doc">
+      <UniqueIdentifier>{df942a55-4dfe-45ea-8fcb-dd862ce2f5e3}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\src\refapp.c">
@@ -29,5 +32,8 @@
     <None Include="..\.github\workflows\ti84-ref_app.yml">
       <Filter>.github\workflows</Filter>
     </None>
+    <None Include="..\README.md">
+      <Filter>_doc</Filter>
+    </None>
   </ItemGroup>
 </Project>
\ No newline at end of file