Fix README

README.md

@@ -1 +1,54 @@
-# python-debian
+# Latest Python for Debian GNU/Linux
+
+# Howto
+
+Install docker and make. Then run
+
+```
+make
+```
+
+To issue build for a particular version
+
+```
+make python3.10-bullseye
+make python3.10-buster
+make python3.10-stretch
+```
+
+Look at the `build/` directory
+
+# Internals
+
+The build process runs inside docker, *without* using cache. It was tested on Linux and macOS. The source code for building packages will be downloaded from the [deadsnakes](https://github.com/deadsnakes) project. After the build, the simple smoke test takes place, installing all packages and running Python script. 
+
+# FAQ
+
+### Which versions of Debian are supported?
+
+All currently maintaied versions: 9 (stretch), 10 (buster), 11 (bullseye)
+
+### Which versions of Python are supported?
+
+Only latest version – Python 3.10
+
+### Why do not build all supported Python?
+
+There is not much sense in that. If you need all Python versions for development, look at the [pyenv](https://github.com/pyenv/pyenv) project or [docker images](https://hub.docker.com/_/python). In other cases, you can safely run old python code in the newest interpreter.
+
+### How long does the full build process take?
+
+Making the fastest build isn't a goal of this project.
+
+  **MacBook Pro 2019, Core i7 (Docker 6 CPU, 8 GB):**  
+
+  Debian 11 (bullseye): *43m29s*</br>
+  Debian 10 (buster): *40m58s*</br>
+  Debian 9 (stretch): *49m36s*</br>
+
+  **AMD Ryzen 5 3600 6-Core / 64G:**
+
+  Debian 11 (bullseye): *32m48s*</br>
+  Debian 10 (buster): *31m11s*</br>
+  Debian 9 (stretch): *25m23s*</br>
+