Salyut 1 was a quick hack put together by Soviet engineers who saw an opportunity to develop something historic. They took the structure of the military Almaz station which was still in development and added existing working hardware to make it a fully functioning space station.
Unfortunately, while it was a success there were problems with both visits to the station, one crew was unable to dock properly, while the second crew died on the way back to Earth.


If you want to find out more about soviet era hardware I suggest "Mir Hardware Heritage'
https://www.hq.nasa.gov/pao/History/S...

And Anatoly Zak's Russian Space Web
http://russianspaceweb.com/