PostgreSQL Adapter

The PostgreSQL adapter connects the Jumentix persistence contract to PostgreSQL. Use cases keep talking to repository ports; database selection stays in composition.

Integrated technology

PostgreSQL through the SQL client profile

Data model: Relational SQL
Jumentix driver: PostgreSQL
Runtime selection: JUMENTIX_DATABASE_DRIVER=PostgreSQL

When to use

Use it for: Transactional systems with relational integrity, indexing, and reporting needs.

When to avoid

Avoid when globally distributed single-digit millisecond writes come first.

How to validate locally

Use the real monorepo smoke test. It validates the adapter lifecycle and prevents shipping configuration that does not connect.


bun run docker:up:postgresql
JUMENTIX_DATABASE_DRIVER=PostgreSQL bun run smoke:db:postgresql

Complete example: Task and Category with a database port

type Category = {
  id: string;
  name: string;
};

type Task = {
  id: string;
  title: string;
  categoryId: string;
  completed: boolean;
};

type Repository<T extends { id: string }> = {
  create(record: T): Promise<T>;
  getById(id: string): Promise<T | undefined>;
  list(): Promise<T[]>;
};

function createRepository<T extends { id: string }>(): Repository<T> {
  const records = new Map<string, T>();

  return {
    async create(record) {
      records.set(record.id, record);
      return record;
    },
    async getById(id) {
      return records.get(id);
    },
    async list() {
      return [...records.values()];
    }
  };
}

const adapterProfile = {
  driver: 'PostgreSQL',
  dataModel: 'Relational SQL',
  smokeTest: 'bun run smoke:db:postgresql'
} as const;

const categories = createRepository<Category>();
const tasks = createRepository<Task>();

export async function seedTaskCatalog() {
  const operations = await categories.create({ id: crypto.randomUUID(), name: 'Operations' });
  const finance = await categories.create({ id: crypto.randomUUID(), name: 'Finance' });

  await tasks.create({
    id: crypto.randomUUID(),
    title: 'Review adapter smoke test',
    categoryId: operations.id,
    completed: false
  });

  await tasks.create({
    id: crypto.randomUUID(),
    title: 'Close billing reconciliation',
    categoryId: finance.id,
    completed: true
  });

  return { adapterProfile, categories: await categories.list(), tasks: await tasks.list() };
}

export async function listTasksForCategory(categoryId: string): Promise<Task[]> {
  const category = await categories.getById(categoryId);

  if (!category) {
    throw new Error('Category not found');
  }

  return (await tasks.list()).filter((task) => task.categoryId === category.id);
}

What changes in production

The example above shows the full contract with an in-memory implementation so it can be read end to end. In production, composition injects the real client selected by JUMENTIX_DATABASE_DRIVER=PostgreSQL; the domain stays the same.