update readme

Author: honzajavorek

README.md

@@ -1,14 +1,21 @@
 # python.cz
 
-Czech Python community homepage powered by [MkDocs](https://www.mkdocs.org/).
+Czech Python community homepage, now powered by [MkDocs](https://www.mkdocs.org/).
 
-# How to run (for development)
+## What happened here?
+
+In 2023-2024, there has been a volunteer-driven effort to revive this site and migrate it from Flask-Frozen to MkDocs.
+For details and motivations, read [#559](https://github.com/pyvec/python.cz/pull/559).
+The main bulk of the work is done, but many small details still need to be finalized.
+The effort is ongoing, and you're welcome to help!
+Check out the [issues](https://github.com/pyvec/python.cz/issues), especially the pinned ones.
+
+## How to run (for development)
 
 1. Clone repository
 1. `poetry install`
 1. `poetry run mkdocs serve`
 
-
 ## License
 
 [MIT](LICENSE)