Is it true that in Russian History Engineers of Castles would be killed when the project was complete?

I saw it in an episode of Life and was wondering if that is true. It was also said that engineers would build trapdoors to try and escape because they knew their fate at the end of the project. Anyone have a link to verify this?Is it true that in Russian History Engineers of Castles would be killed when the project was complete?
I've heard the same about many other countries, that's why I think it didn't really happen. Not very often, anyway. Engineers were very valuable in those days. For more than they are now. So why kill the goose with the golden egg?





Most fortifications are pretty much standard. You build a defense against a known threat, using the terrain. It isn't rockets science, and there isn't much secrecy in it. The enemy knows roughly what they are up against anyway.





Castles with secret entrances or passageways are exceptional. Albino pandabears are much more common. Fortifications did have 'secret' doors, but the secrecy was in being less visible to the enemy, so they could be used for surprise sorties.





It would take a certified madman to do it, but then: Ivan the Terrible was...Is it true that in Russian History Engineers of Castles would be killed when the project was complete?
I don't know how often it happened but I do know that Ivan the Terrible blinded the guy who designed the Kremlin so that he couldn't make anything else as nice.
I have heard that before but I didn't know it was a Russian thing. I only know it was during the Middle Ages.