Bolt

aws-chunked payload encoding streams large S3 uploads in signed chunks — no full-body buffering, per-chunk SigV4 integrity.

Momo’s transport layer grew from TCP to a QUIC/TLS 1.3 fan-out — fixing handshake, ACK framing, deadlines, and TLS identity along the way.

The [storage] backend seam swaps blob storage (local, nfs, s3, raw) behind one Store interface, keeping CAS metadata local.

External S3 clients like aws-cli don’t send momo headers — the server detects this and downgrades client-side replication modes to server-side alternatives, ensuring replication never silently drops.

Weighted rendezvous hashing picks replicas deterministically and peer-equally without a central allocator — later hardened for failure domains. Teaches: content-hash-based placement, weighted rendezvous hashing, deterministic stable sort, failure domain filtering.

Systematic defensive coding: nil-safety, numeric overflow guards, resource lifecycle discipline, panic recovery at every boundary, and concurrency safety under -race.

Chain, Splay, and Primary-Splay replication — and the metrics-driven controller that switches between them at runtime.

Identify every object by its SHA-256 content hash — server-side dedup, verify-on-read, and a path that later mounted a filesystem. Teaches: content addressing principles, single write chokepoint, Bolt/Sentinel patterns.