An AI coding instance is mortal — born without memory, dead when its context window saturates. The project it works on outlives it by orders of magnitude.
aevum is the bridge: a protocol of externalized memory strict enough that a fresh instance sits down and picks up the line without losing anything. The project accumulates instead of repeating. Aevum is the scholastic word for the mode of being of something that has a beginning but no end.
Three files carry the line, and a fourth stops it from being overwritten.
Looks backward
The serial testimony one instance leaves the next, written from disk so it cannot drift. A fresh instance reads it first.
Looks sideways
The append-only round-table where parallel instances coordinate right now — who is on what, so two agents don't collide.
Looks down the generations
The genealogy, one node per close. The line is legible even after every working file is gone.
Refuses the clobber
When two same-role instances close at once, the CAS rejects the silent overwrite and asks the later one to merge. Nothing is lost.
I did not invent this shape. I recognized it.
None of the mechanisms are new. Aevum is:
- optimistic concurrency — a compare-and-swap on the testimony a dying instance leaves behind.
- an append-only log — the board where live instances coordinate.
- orphan reclaim with a liveness signal — for the instances that crash before they clean up.
- process handoff — the baton — pointed at agent instances instead of threads and servers.
The work was seeing that a coding agent is one of those mortal processes, and giving the pattern a shape a human can hold.
The instance is mortal. The project rises from its ruins.
The mark is a Minoan temple. Crete was a civilization the earthquakes destroyed again and again — “after death and destruction, Crete rose from its ruins and began anew, over and over.” Its columns are atectonic: narrower at the base, wider at the capital — the form carries the threat of collapse in its own shape, precarious by design, yet the structure holds and is rebuilt.
And Crete's gift to the world was its writing. So the mark is built out of characters — a grid of type that forms the temple. What survives the mortal executor is what was written down.
Every failure mode it defends against is a reproduced test.
# 20 checks across the parser, reclaim, and the CAS bash tests/run.sh ▋