Build a durable key-value store

Make a key-value store survive a fresh object instance, then adapt it to small persisted files.

Role: Software Engineer, Infrastructure
Difficulty: Medium
Practice time: 60 min

The challenge

Make a key-value store recover its contents when a fresh object is created. Keys and values can contain arbitrary Unicode and control characters, and the exercise supplies byte-conversion helpers and a mock filesystem instead of a ready-made object serializer.

After the first part passes, adapt the persistence design to a small per-file size limit. You must preserve the meaning of the stored data as its physical representation changes.

What you'll practise

Unambiguous encoding
Preserve keys and values containing arbitrary Unicode and control characters.
Bounded persistence
Adapt the representation so the whole store remains recoverable within file limits.

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solution.pyPython 3.13

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Build a durable key-value store

The challenge

What you'll practise

Unambiguous encoding

Bounded persistence

Build an in-memory cloud storage service

Flatten and rebuild nested structures

Implement an LRU cache

The challenge

What you'll practise

Unambiguous encoding

Bounded persistence

Related challenges

Build an in-memory cloud storage service

Flatten and rebuild nested structures

Implement an LRU cache