d1-kyt

Type-safe Cloudflare D1 toolkit built on Kysely and Valibot. Define your schema once in Valibot — get SQL migrations and fully-typed queries with no code generation.

import { defineTable, defineIndex, InferDB, createQueryBuilder, queryAll, queryFirst } from 'd1-kyt';
import * as v from 'valibot';

export const users = defineTable('users', {
  email:    v.string(),
  verified: v.boolean(),                          // stored 0/1 → returned as boolean
  prefs:    v.object({ theme: v.string() }),      // stored as JSON → returned as object
});

export const posts = defineTable('posts', {
  title:    v.string(),
  views:    v.pipe(v.number(), v.integer()),
  authorId: v.pipe(v.number(), v.integer()),
}, {
  foreignKeys: [{ columns: ['authorId'], references: users }],
});

export const postsTitleIdx = defineIndex(posts, ['title'], { unique: true });

export type DB = InferDB<{ users: typeof users; posts: typeof posts }>;
export const db = createQueryBuilder<DB>();

// prefs is { theme: string }, verified is boolean — deserialized automatically
const verified = await queryAll(
  env.DB,
  db.selectFrom('users').selectAll().where('verified', '=', true).compile(),
);

// full Kysely — joins, subqueries, window functions, all type-checked
const popular = await queryFirst(
  env.DB,
  db.selectFrom('posts')
    .innerJoin('users', 'users.id', 'posts.authorId')
    .select(['posts.title', 'posts.views', 'users.email'])
    .where('posts.views', '>', 1000)
    .orderBy('posts.views', 'desc')
    .compile(),
);

Install

npm install d1-kyt kysely valibot

Workflow

schema.ts  →  schema:diff  →  .sql migration  →  wrangler apply  →  typed queries

Define tables with Valibot types in schema.ts
Run d1-kyt schema:diff <name> — diffs against a snapshot, writes a .sql migration
Apply with wrangler d1 migrations apply <db> --local
Use $inferSelect / $inferInsert from your schema for typed queries

Quick start

d1-kyt init                              # scaffold config + schema in db/
d1-kyt schema:diff create_posts          # generates db/migrations/0001_create_posts.sql
wrangler d1 migrations apply <db> --local

Schema

Valibot → SQL type mapping

Valibot	SQL	Notes
`v.string()`	TEXT NOT NULL
`v.number()`	REAL NOT NULL
`v.pipe(v.number(), v.integer())`	INTEGER NOT NULL
`v.boolean()`	INTEGER NOT NULL	stored as 0/1, returned as `boolean`
`v.object({...})` / `v.array(...)`	TEXT NOT NULL	JSON serialized
`v.optional(X)`	nullable
`v.nullable(X)`	nullable
`v.optional(X, default)`	DEFAULT val

Auto columns

Every table gets id (INTEGER PRIMARY KEY AUTOINCREMENT), createdAt (TEXT), and updatedAt (TEXT) with an AFTER UPDATE trigger. All configurable:

// Disable everything
defineTable('events', { uuid: v.string() }, {
  primaryKey: false, createdAt: false, updatedAt: false,
})

// Custom names
defineTable('users', { email: v.string() }, {
  primaryKeyColumn: 'user_id',
  createdAtColumn: 'created_at',
  updatedAtColumn: 'updated_at',
})

Type inference

type PostRow = typeof posts.$inferSelect;
// { id: number; title: string; published: boolean; views: number; ... }

type NewPost = typeof posts.$inferInsert;
// { title: string; published: boolean; views: number; id?: number; ... }

Foreign keys

export const categories = defineTable('categories', { name: v.string() });

export const posts = defineTable('posts', {
  title:      v.string(),
  categoryId: v.pipe(v.number(), v.integer()),
}, {
  foreignKeys: [{
    columns:    ['categoryId'],
    references: categories,
    refColumns: ['id'],           // optional — defaults to the referenced table's PK
    onDelete:   'CASCADE',        // CASCADE | SET NULL | RESTRICT | NO ACTION
    onUpdate:   'NO ACTION',
  }],
});

PRAGMA foreign_keys = ON is automatically prepended to any migration that includes FK constraints.

Adding a FK column to an existing table requires a nullable column (SQLite limitation):

deptId: v.optional(v.pipe(v.number(), v.integer()))  // ✓ nullable allows inline REFERENCES

Indexes

// Basic unique index
export const postsSlugIdx = defineIndex(posts, ['slug'], { unique: true });

// Composite index
export const postsAuthorViewsIdx = defineIndex(posts, ['authorId', 'views']);

// Partial index — only indexes rows matching the WHERE clause
export const postsPublishedIdx = defineIndex(posts, ['createdAt'], {
  where: 'published = 1',
});

// Custom index name
export const postsSearchIdx = defineIndex(posts, ['title'], {
  name: 'posts_title_fts_idx',
});

Columns are type-checked against the table definition at compile time.

CLI

d1-kyt init [--dir <dir>]
d1-kyt schema:diff <name> [--dir <dir>] [--schema <path>]

Always commit schema.json alongside each .sql migration — it is the diff baseline.

Config

// db/config.ts
import { defineConfig } from 'd1-kyt';

export default defineConfig({
  migrationsDir: 'db/migrations',
  namingStrategy: 'sequential',  // or 'timestamp'
});

D1 limits

d1-kyt enforces D1's hard limits at runtime and emits warnings in generated migrations:

Limit	Value
Bound parameters per query	100
SQL statement length	100,000 chars
Columns per table	100 (warning in migration)

Custom validators:

import { D1_VALIDATORS, runValidators } from 'd1-kyt';
import type { QueryValidator } from 'd1-kyt';

const noDrops: QueryValidator = (q) => {
  if (q.sql.includes('DROP')) throw new Error('DROP not allowed');
};

await queryAll(env.DB, query, undefined, [...D1_VALIDATORS, noDrops]);
await queryAll(env.DB, query, undefined, []);  // disable all checks

API reference

Schema

Export	Description
`defineTable(name, columns, opts?)`	Define a table; returns `SchemaTable` with `$inferSelect` / `$inferInsert`
`defineIndex(table, columns, opts?)`	Define an index; columns are type-checked. `opts`: `unique`, `name`, `where` (partial index)
`defineTrigger(name, opts)`	Define a custom trigger
`InferDB<Tables>`	Infer a Kysely-compatible `DB` type

Execution

Export	Description
`createQueryBuilder<DB>()`	Compile-only Kysely instance
`queryAll(db, query, table?, validators?)`	All rows; JSON + boolean columns auto-deserialized
`queryFirst(db, query, table?, validators?)`	First row or null; auto-deserialized
`queryRun(db, query, validators?)`	INSERT / UPDATE / DELETE
`queryBatch(db, queries, validators?)`	Atomic batch

Validators

Export	Description
`D1_VALIDATORS`	Default validator array
`d1MaxParams`	Enforces ≤ 100 bound parameters
`d1MaxSqlLength`	Enforces ≤ 100,000 char SQL
`runValidators(query, validators?)`	Run validators manually

License

MIT