Verified execution runtime unifying state, persistence, and replication. http://git.yeowoo.org/pure/atom?h=master 2026-09-25T08:33:43Z 2026-09-25T08:33:43Z eunhhu necpition205@gmail.com 2026-09-25T08:33:43Z urn:sha1:6a28879bd56354483fe940c0c80d511eccb89983 store-tree.c keeps every document in one append-only file as a persistent B-tree of byte extents, with the key catalog in the same structure. A splice writes only the changed leaf and path; unchanged extents are shared between versions, readers take no lock, and two alternating head slots publish a commit after its nodes are durable. Compaction rewrites reachable nodes. On the recorded ext4 host a durable 1-byte middle insert into a 1 MiB document took 8.58 ms against 78.51 ms for the default store, and the real TUI's Ctrl+S after typing took 16.60 ms against 84.59 ms. check-tree runs the store's crash/oracle tests and the unchanged runtime, splice, async and real-PTY editor checks on it. It stays opt-in: linked code is 12.7 KB larger and contiguous multi-leaf reads copy.