# Install FluctlightDB

FluctlightDB runs inside your Python process. A brain is a directory. There is no server to start and no account to open. The software is beta.

## Install

`pip install "fluctlightdb[native]"`

The [native] extra pulls the compiled Rust core. Without it you get the pure-Python fallback, which is slower and is not what the measurements were taken on.

## A first brain

This is the canonical sample. It was run against the published package, and it is the same sample the rest of the site shows.

```python
from fluctlightdb import connect_embedded

brain = connect_embedded("./my-agent-brain")   # one directory per agent, in-process
brain.experience("User prefers dark mode", context="settings", salience=0.7)
brain.experience("Wallet balance is $42.10", context="ledger:wallet",
                 verified=True, source_uri="file://wallet.json")

hits = brain.activate("dark mode")             # cue -> ranked recalls
brain.checkpoint()                             # durable; survives restart
```

## Checkpoint

A write-ahead log and atomic checkpoints put the brain directory on disk. Crash recovery is exercised in CI with SIGKILL mid-write and torn WAL tails.

Nothing is durable until checkpoint() returns.

## Where this goes next

- [Quickstart](/quickstart)
- [Documentation](/docs)
- [Facts](/facts.json)