# LSM in a Week

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Build a simple key-value storage engine in a week!

## Tutorial

The tutorial is available at [https://skyzh.github.io/mini-lsm](https://skyzh.github.io/mini-lsm). You can use the provided starter
code to kick off your project, and follow the tutorial to implement the LSM tree.

## Development

```
cargo x install-tools
cargo x check
cargo x book
```

If you changed public API in the reference solution, you might also need to synchronize it to the starter crate.
To do this, use `cargo x sync`.

## Progress

The tutorial has 8 parts (which can be finished in 7 days):

* Day 1: Block encoding. SSTs are composed of multiple data blocks. We will implement the block encoding.
* Day 2: SST encoding.
* Day 3: Engine. In this day we will get a functional (but not persistent) key-value engine with `get`, `put`, `delete`
  API.
* Day 4: Block cache. To reduce disk I/O and maximize performance, we will use moka-rs to build a block cache for the
  LSM tree.
* Day 5: Compaction. Now it's time to maintain a leveled structure for SSTs.
* Day 6: Recovery. We will implement WAL and manifest so that the engine can recover after restart.
* Day 7: Bloom filter and key compression. They are widely-used optimizations in LSM tree structures.

We have reference solution up to day 3 and tutorial up to day 1 for now.