What is monolayer?

monolayer-pg is a PostgreSQL database schema manager for TypeScript projects built on top of kysely with:

• Declarative, type-safe database schema definition.
• Type-safe database client(s) for kysely (no codegen 🎉).
• An advanced migration system with non-blocking migrations by default, migrations by phases, and detailed warnings.
• Comprehensive Zod validations for all supported data types (no codegen 🎉) for kysely.
• Support for multiple databases.
• Support for multiple schemas per database.
• Effortless Prisma integration.

Here's a taste of how you define database schemas with monolayer-pg:

const users = table({
  columns: {
    id: integer().generatedAlwaysAsIdentity(),
    email: text().notNull(),
    name: text(),
  },
  constraints: {
    primaryKey: primaryKey(["id"]),
    unique: [unique(["email"])],
  },
  indexes: [index(["email"])],
});

const posts = table({
  columns: {
    id: integer().generatedAlwaysAsIdentity(),
    title: text().notNull(),
    content: text(),
    published: boolean().default(false),
    authorId: integer(),
    createdAt: timestampWithTimeZone().notNull().default(sql`now()`),
    updatedAt: timestampWithTimeZone().notNull().default(sql`now()`),
  },
  constraints: {
    primaryKey: primaryKey(["id"]),
    foreignKeys: [
      foreignKey(["authorId"], users, ["id"])
        .deleteRule("set null")
        .updateRule("cascade"),
    ],
  },
  indexes: [index(["authorId"])],
});

export const dbSchema = schema({
  tables: {
    users,
    posts,
  },
});

Head over to the Quickstart and begin using monolayer-pg!