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2026-08-22 release · embed · reliability

Embed train v0.2.5 — crash-loop, soak, pinned LSM

f4kvs-ffi v0.2.5 pins f4kvs-lsm v0.3.6. Crash-loop 50× SIGKILL with zero loss, two-hour soak with 10/10 restart anchors. Cluster stays lab.

PugDB is the public name of F4KVS: a Rust LSM you embed, not a cloud you rent. The production path is still FFI + LSM. The server monorepo is the reliability harness. The cluster is lab.

Pins (2026-08-22)

ComponentTagRole
Enginef4kvs-lsm v0.3.6Canonical LSM (hot-path merged: prefix scan, SST pin share, compacted SST reclaim)
Embed APIf4kvs-ffi v0.2.5C ABI + Go wrappers, cursor pages, prefix scan, pin on lsm v0.3.6
Serverf4kvs-v2 v0.2.0Staging, soak, hostile suites — not a generic prod cluster GO

Owner GO for alpha embed still stands (2026-07-23): memoirs / RAG preprod. NO-GO generic production cluster.

Reliability, not charts

Re-run on 17–18 August after the LSM hot-path landed:

  • Crash-loop — 50 rounds × 1,000 ops, killed with SIGKILL, 0 loss (soak-20260817T200639Z).
  • Soak 1h + 1h — 1,661,444 cache ops at 462/s, 10/10 anchors after restart, 0 health failures (soak-20260818T023658Z).
  • Meso 100k — 100,000 × 4 KB RAG-shaped chunks, 100,050 / 100,050 keys after reopen (July native engine run; integrity gate unchanged).
  • Server 20k microbench @f52790c: put 9,070 / get 29,412 / mixed 37,594 ops/s, 0 errors.

We still publish a small YCSB A/B/D 10k table on /bench, and a larger 432-cell matrix by median (some QL cells lose). We do not headline a 25× PostgreSQL average, and we do not say “faster than RocksDB”.

What this is for

  • Embedded storage under self-hosted RAG and memoirs-style apps (C / Go).
  • Teams that want reproducible gates (crash-loop, soak, post-restart row count) more than a leaderboard screenshot.
  • Not a claim that PugDB powers every Noematic product. Media Cataloger still defaults to Badger for dups/index; PugDB is opt-in there.

Explore the numbers on /bench. Previous note: alpha embed / meso 100k.

— The PugDB team