Update readme

README.md

@@ -1,7 +1,59 @@
 # Pango Build
 
-Buiding Pango and Cairo for use of some Python Projects. Used mainly for creating wheels for
-[manimpango](https://github.com/manimcommunity/manim).
+`pango-build` is mainly used for creating wheels for [ManimPango](https://github.com/manimcommunity/manim). It provides a static Windows build of pango including all its dependencies which ManimPango uses for its binary Windows wheels.
+
+In addition to pango it also provides a static build of
+[pkgconf](https://github.com/pkgconf/pkgconf) which is required by ManimPango
+during its wheel build process for locating dependencies.
+
+The build process is based on the [meson](https://mesonbuild.com/) build system
+and uses Visual Studio on GitHub Actions to automatically build and publish
+everything. See the [workflow file](.github/workflows/main.yml) for details. You
+can of course also build everything locally yourself, see the instructions
+below.
+
+## Manual build instructions
+
+```bash
+# install meson and ninja
+pip install -r requirements.txt
+
+# build pango
+cd pango-build
+meson setup buildDir --prefix=/
+meson compile -C buildDir
+meson install -C buildDir --destdir ../dist
+# see ./dist for the result
+
+# build pkgconf
+cd ../pkgconf-build
+meson setup buildDir --prefix=/
+meson compile -C buildDir
+meson install -C buildDir --destdir ../dist
+# see ./dist for the result
+```
+
+## Updating dependencies
+
+All dependencies and pango itself are included via the [meson wrap
+system](https://mesonbuild.com/Wrap-dependency-system-manual.html) and we depend
+on the [meson WrapDB](https://github.com/mesonbuild/wrapdb) for updates. The
+following is required to pull in new versions from pypi and wrapdb:
+
+```bash
+# manually update meson/ninja in requirements.txt
+pip install -r requirements.txt
+# update wrap files from wrapdb
+meson wrap update --sourcedir pango-build
+meson wrap update --sourcedir pkgconf-build
+```
+
+## Creating a new release
+
+- Create a new release in the GH UI
+- GHA will do the rest
+
+## License
 
 All the build script are licensed under Apache License 2.0, and the binaries in release section
 is under LGPL same as Pango's license.