Installation Steps for creating Async APIs using FastAPI

Developer's Hub — Sun, 04 Jan 2026 05:50:14 +0000

To create a backend with FastAPI using asynchronous APIs and PostgreSQL, you will need a set of libraries that support the Python asyncio event loop.

For a modern 2026 stack, the following libraries are recommended:

1. Core Framework & Server

FastAPI: The web framework for building your APIs.
Uvicorn: An ASGI server required to run your FastAPI application. Use the [standard] extra for high-performance dependencies like uvloop.

bash
```
pip install fastapi "uvicorn[standard]"
```
Use code with caution.

2. Database Driver (Async)

For PostgreSQL specifically, you need an asynchronous driver.

asyncpg: Widely regarded as the fastest asynchronous PostgreSQL client library for Python.
psycopg (v3): A modern alternative that supports both sync and async operations natively.

bash
```
pip install asyncpg
# OR
pip install "psycopg[binary]"
```
Use code with caution.

3. ORM & Data Models

You can use SQLAlchemy 2.0+ directly or SQLModel, which combines SQLAlchemy and Pydantic.

SQLAlchemy: Ensure you use the [asyncio] extra for built-in async support.
SQLModel: A wrapper that simplifies using SQLAlchemy with Pydantic, designed specifically for FastAPI.

bash
```
pip install "sqlalchemy[asyncio]"
# OR
pip install sqlmodel
```
Use code with caution.

4. Database Migrations

Alembic: The standard tool for handling database schema migrations. While it runs synchronously, it can be configured to work with async drivers in your env.py file.

bash
```
pip install alembic
```
Use code with caution.

5. Utility & Configuration

pydantic-settings: For managing environment variables and application configurations.
python-dotenv: To load configuration from .env files.

bash
```
pip install pydantic-settings python-dotenv
```
Use code with caution.

Summary Installation Command

You can install the primary "async stack" with this single command:

bash

pip install fastapi "uvicorn[standard]" "sqlalchemy[asyncio]" asyncpg sqlmodel alembic pydantic-settings

Use code with caution.

Note on Connection Strings: When using these libraries, ensure your database URL starts with postgresql+asyncpg:// instead of the standard postgresql:// to trigger the asynchronous engine.

Forem: Developer's Hub

Installation Steps for creating Async APIs using FastAPI