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Welcome to The Keeper's Corner

A digital notebook of ideas, experiments, and things worth remembering. Built for engineers, leaders, and curious minds.

Your database failed over. Is your position still real?

2026-07-05 • 8 min read • by Vahid Negahdari

After a failover the new primary is a different server, and the log position your CDC engine was tracking may not exist on it. Continuing anyway silently skips data. How DeltaForge detects the swap by server identity, checks the position is reachable, and halts loudly instead of skipping.

rust cdc databases data engineering mysql postgres distributed systems open source

logdrain: Fast, Embeddable Log-Template Mining in Rust

2026-06-28 • 16 min read

I open-sourced logdrain, an online Drain log-template miner in Rust that turns millions of noisy log lines into a handful of templates, with path-preserving tokenization, masks, and stack-trace clustering.

rust observability logging ai agents llm open source

Your snapshot succeeded, and you still lost data

2026-06-28 • 8 min read • by Vahid Negahdari

The classic CDC landmine: a long initial snapshot finishes cleanly, but the log position it captured was purged while it ran, so streaming resumes with a silent gap. How DeltaForge makes the handoff safe with a consistent read, a captured position, and three layers of retention guards.

rust cdc databases data engineering mysql postgres open source

Exactly-once is a per-sink promise

2026-06-21 • 10 min read • by Vahid Negahdari

In a CDC pipeline that fans out to Kafka, Redis, NATS, and S3 at once, exactly-once cannot be a single promise. How DeltaForge makes an honest one per sink: checkpoint-after-ack, independent per-sink checkpoints, and pushing exactly-once to the edge where the sink can actually support it.

rust cdc databases data engineering distributed systems kafka open source

Would you notice a new field in your data pipeline?

2026-06-14 • 12 min read • by Vahid Negahdari

Schema sensing reveals the shape of data hiding inside JSON columns, so platform and compliance teams notice when a new field appears. The catch: dynamic keys make naive inference cry wolf on every event. How DeltaForge fixes it with HyperLogLog and SpaceSaving.

rust cdc databases data engineering postgres mysql open source