> For the complete documentation index, see [llms.txt](https://crystal-garage.gitbook.io/lustra-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://crystal-garage.gitbook.io/lustra-docs/model/transactions-and-save-points.md).

# Transactions & Savepoints

Lustra exposes transaction helpers through `Lustra::SQL`. Use them when multiple writes must succeed or fail as one unit.

```crystal
Lustra::SQL.transaction do
  user.update!(balance: user.balance - 100)
  recipient.update!(balance: recipient.balance + 100)
end
```

This section covers:

* `transaction` for atomic work
* `with_savepoint` for nested rollback points
* `rollback`, `rollback_transaction`, and `after_commit`
* connection pool behavior


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