# Kysely v0.30.0-beta.1 — 0.30.0-beta.1

- Product: Kysely (https://whatsnew.fyi/product/kysely)
- Vendor: Kysely
- Date: 2026-07-26
- Version: v0.30.0-beta.1
- Original notes: https://github.com/kysely-org/kysely/releases/tag/v0.30.0-beta.1
- Permalink: https://whatsnew.fyi/product/kysely/releases/v0.30.0-beta.1
- Labels: Pre-release

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Add transactionMode property to Migrator accepting 'per-run', 'per-migration', or 'none' to control transaction behavior across migrations
- **added** — Add defineMigration helper function to simplify migration writing and contract requirements
- **added** — Add migrateTo(name, { direction: 'Up' | 'Down' }) method to Migrator to enforce migration direction
- **added** — Support mysql2/promise in MysqlDialect in addition to the callback-based mysql2 import
- **added** — Deny passing BLOB-like columns to SQLite JSON helpers with compile-time type errors
- **deprecated** — Deprecate disableTransactions option in favor of transactionMode property
- **changed** — Per-migration transaction configuration now allows each migration to specify whether it runs in its own transaction via config: { transaction: false }

Hey 👋 

0.30 season is upon us. `pnpm i kysely@next` and get a sneak peak into the future!

We've got a new `transactionMode: 'per-run' | 'per-migration' | 'none'` property you can pass to `Migrator` or it's methods. 

- `'per-run'` is the classic behavior you're used to where `kysely` wrap the entire run in a transaction when your dialect supports transactional DDL.
- `'per-migration'` enables each migration to pick whether it runs in its own transaction or not. Just expose `config: { transaction: false }` from the module, right next to the `up`/`down` functions.
- `'none'` means no transactions are used, which is similar to the now deprecated `disableTransactions: true`.

```ts
import * as fs from 'node:fs/promises'
import * as path from 'node:path'
import { FileMigrationProvider, Migrator } from 'kysely/migration'

const migrator = new Migrator({
  db,
  provider: new FileMigrationProvider({
    fs,
    migrationFolder: path.join(import.meta.dirname, 'migrations'),
  }),
  transactionMode: 'per-migration', // <-------------------------------
})

await migrator.migrateToLatest()
```

We've got a new `defineMigration` helper function that you can use to easily write your migrations and meet the contract requirements:

```ts
import { defineMigration } from 'kysely/migration'

export default defineMigration({
  up: async (db) => {
    // ...
  },

  config: { transaction: false }, // <--------------------
})
```

You can now use `mysql2/promise`, where in the past it would hang forever since we only supported the callback style of `mysql2` root import.

##### 🚀 Features

* feat(migrator): add `migrateTo(name, { direction: 'Up' | 'Down' })` to enforce direction. by @igalklebanov in https://github.com/kysely-org/kysely/pull/1957

###### PostgreSQL 🐘 / MSSQL 🥅 

* feat: Per-migration transaction configuration by @lourd & @igalklebanov in https://github.com/kysely-org/kysely/pull/1671

###### MySQL 🐬 

* feat(mysql): support both `mysql2` and `mysql2/promise` in `MysqlDialect`. by @igalklebanov in https://github.com/kysely-org/kysely/pull/1958

###### SQLite 📘 

* feat: deny passing BLOB-like columns to SQLite JSON helpers by @hwisu & @igalklebanov in https://github.com/kysely-org/kysely/pull/1698

##### 🐞 Bugfixes

##### 📖 Documentation

##### 📦 CICD & Tooling

##### ⚠️ Breaking Changes

* `disableTransactions` is deprecated. Use the new `transactionMode: 'none'`, or `transactionMode: 'per-migration'` with combination of `config: { transaction: false }`.

###### SQLite 📘 

* Trying to pass records with `BLOB` columns in JSON helpers emits compile-time errors - e.g.
	```ts
	KyselyTypeError<'SQLite does not support passing `BLOB` values to `json_object`. Cast to `TEXT`.'>
	```

##### 🐤 New Contributors

* @lourd made their first contribution in https://github.com/kysely-org/kysely/pull/1671

##### What's Changed

**Full Changelog**: https://github.com/kysely-org/kysely/compare/4ba0bd495a4cbe11d8d58ef02537586dc4d56532...v0.30.0-beta.1