Bitcask

This project is a simple implementation of Bitcask, a log-structured key/value store design described by Basho in the Bitcask paper.

The goal of this repository is educational: it shows the core ideas behind Bitcask in a small Go codebase.

What It Does

• Stores records in append-only .data files.
• Keeps an in-memory key directory for fast lookups.
• Supports put, get, delete, and listing keys.
• Uses tombstone records for deletes.
• Rebuilds the key directory from data files on startup.
• Rotates data files when the active file grows too large.
• Includes basic compaction support.
• Verifies records with CRC checksums.

Running

go run .

This starts a small REPL backed by ./mydb.

Available commands:

put <key> <value>
get <key>
delete <key>
keys
exit

Reference

• Bitcask paper / introduction
• Bitcask: A Log-Structured Hash Table for Fast Key/Value Data, Basho