Systems
End-to-end builds — from a naive implementation to a production-grade design, step by step.
Distributed Cache
A sharded, replicated in-memory cache: consistent-hashing routing, LRU eviction, replica failover, single-flight stampede control, and hot-key fan-out.
Document Database
A schema-flexible document store with secondary indexes, walked from a single in-memory collection up through leader-follower and leaderless quorum replication.
Time-Series Database
Ingest and query high-volume metrics: append-only columnar chunks, delta-of-delta + XOR compression, time-based block pruning, a label inverted index, and cardinality control.
Persistent Key-Value Store
An embedded, crash-safe KV store built on an LSM tree: WAL durability, memtable flushes, Bloom-filtered reads, compaction, and MVCC snapshots.