[sudahtigabulan]

This reminds me of ClearCase and its MVFS.

Builds were audited by somehow intercepting things like open(2) and getenv(3) invoked by a compiler or similar tool, and each produced object had an associated record listing the full path to the tool that produced it, its accurate dependencies (exact versions), and environment variables that were actually used. Anything that could affect the reproducibility was captured.

If an object was about to be built with the exact same circumstances as those in an existing record, the old object was reused, or "winked-in", as they called it.

It also provided versioning at filesystem level, so one could write something like file.c@@/trunk/branch/subbranch/3 and use it with any program without having to run a VCS client. The version part of the "filename" was seen as regular subdirectories, so you could autocomplete it even with ancient shells (I used it on Solaris).