Migrate MySQL, Postgres, SQLite, or SQL Server to Cloudflare D1 — with checkpoints and integrity checks

#typescript #database #opensource #cloudflarechallenge

Moving an existing database to Cloudflare D1 sounds simple until you hit type mismatches, partial failures halfway through a million-row import, or find out afterwards that 3,000 rows silently didn't land.

We built @zintrust/d1-migrator to solve exactly that.

What it does

Migrates MySQL, PostgreSQL, SQLite, or SQL Server → Cloudflare D1
Resumable — checkpoints every N rows so a failure doesn't mean starting from zero
Data integrity verified — row counts + checksums validated after every batch
Dry-run mode — preview the full migration without touching D1
Interactive mode — guided prompts for tables with D1 compatibility warnings
Zero downtime — runs against your live database
TypeScript-first — full types, works with @zintrust/core

Install

npm install @zintrust/d1-migrator

Quickest possible migration (1-line CLI)

DB_CONNECTION=mysql DB_READ_HOSTS=127.0.0.1 DB_PORT=3306 DB_DATABASE=mydb DB_USERNAME=root DB_PASSWORD=secret D1_TARGET_DB=my-d1-db zin migrate-to-d1

All values can also be passed as explicit CLI flags. The order of precedence is: CLI flag → env var → default.

TypeScript API

import { D1Migrator } from '@zintrust/d1-migrator';

const progress = await D1Migrator.DataMigrator.migrateData({
  sourceConnection: 'mysql://user:password@localhost:3306/mydb',
  sourceDriver: 'mysql',
  targetDatabase: 'my-d1-db',
  targetType: 'd1',
  batchSize: 1000,
  checkpointInterval: 10000,
});

console.log(`Migrated: ${progress.processedRows} rows`);

Type conversions handled automatically

Source	D1 / SQLite	Notes
DATETIME	TEXT (ISO 8601)	Auto-converted
BIGINT	TEXT	Precision preserved
DECIMAL	TEXT	Precision preserved
JSON	TEXT	Serialized JSON string
BLOB	BLOB	Binary preserved

Resuming after a failure

zin migrate-to-d1 --resume --migration-id <id>

Checkpoints are stored in .wrangler/state/v3/migrations/ — only unprocessed rows are re-migrated.

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