Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Newsletter Hub
Free Learning
Arrow right icon
timer SALE ENDS IN
0 Days
:
00 Hours
:
00 Minutes
:
00 Seconds
Python Microservices with FastAPI
Python Microservices with FastAPI

Python Microservices with FastAPI: Design production-ready, AI-enabled microservices with Python

Arrow left icon
Profile Icon Giunio De Luca Profile Icon Igor Benav
Arrow right icon
Early Access Early Access Publishing in Jun 2026
$44.99
Paperback Jun 2026 360 pages 1st Edition
eBook
$32.39 $35.99
Paperback
$44.99
Subscription
Free Trial
Renews at $19.99p/m
Arrow left icon
Profile Icon Giunio De Luca Profile Icon Igor Benav
Arrow right icon
Early Access Early Access Publishing in Jun 2026
$44.99
Paperback Jun 2026 360 pages 1st Edition
eBook
$32.39 $35.99
Paperback
$44.99
Subscription
Free Trial
Renews at $19.99p/m
eBook
$32.39 $35.99
Paperback
$44.99
Subscription
Free Trial
Renews at $19.99p/m

What do you get with Print?

Product feature icon Instant access to your digital copy whilst your Print order is Shipped
Product feature icon Paperback book shipped to your preferred address
Product feature icon Redeem a companion digital copy on all Print orders
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
Modal Close icon
Payment Processing...
tick Completed

Shipping Address

Billing Address

Shipping Methods
Table of content icon View table of contents Preview book icon Preview Book

Python Microservices with FastAPI

1

Launching the Platform: FastAPI Project Basics

Welcome to the first chapter of our journey into modern microservices. Whether you’re a developer eager for hands-on skills or an architect seeking a clear framework, this chapter is your starting point.

We’ll cut through the buzz and misconceptions to explain what microservices truly are and why they matter. You’ll explore the core principles behind microservice design, what distinguishes successful architectures, and how to determine if this approach is right for your platform.

By the end of this chapter, you’ll have a clear understanding of what microservices are, and what they are not. You’ll also know how to kickstart a FastAPI application and set up your development environment for the best experience from day one. Furthermore, you’ll gain an overview of modern Python package managers.

In this chapter, we’ll cover the following main topics:

  • Refresh some conceptions about Microservices...

Technical requirements

Before we dive into the hands-on work, let’s take a moment to talk about what you’ll need to successfully follow along with this chapter.

  • You should already be familiar with Python; the code is tested with Python 3.13 .
  • Also, being familiar with a virtual environment or simply an isolated environment could help, but is not mandatory
  • You should have your code editor already set up: whether you love VS Code, Cursor, PyCharm, Vim, or even Emacs, any editor that supports Python will work. The important thing is that you can move quickly and comfortably through your files.
  • Being familiar with a command-line interface is an advantage since much of your interaction will happen in the terminal or command prompt. If you’re new to it, don’t worry—mastery comes with practice, and every step you take here deepens your understanding.
  • Internet access: you’ll need it for installing dependencies, checking documentation, and occasionally...

What makes a Modern Microservice Project?

Before diving into project setup and code, let’s clarify what this book is really about: microservices.

In recent years, the term is everywhere—conference talks, architecture diagrams, job interviews, you name it—but it’s often misunderstood.

Let’s take a moment to unpack what a microservice is, what it isn’t, and why we’re choosing this architecture for our Platform.

According to Martin Fowler from the book Patterns of Enterprise Application Architecture:

The microservice architectural style is an approach to developing a single application as a suite of small services, each running in its own process and communicating with lightweight mechanisms, often an HTTP resource API.

We can think of a microservice as an independently deployable unit of software that focuses on doing one business capability well. It runs in its own process, communicates with other services over the network...

Start the Project with uv

When building complex systems, it's much easier if you have a solid approach to organizing and managing your code. This helps keep things less complicated and makes development more enjoyable.

One great advantage for developers is working with isolated and reproducible environments. These provide several benefits:

  • They prevent changes to your system's main Python installation
  • They ensure that dependencies stay consistent across different machines.
  • They allow different projects or microservices to use their own versions of dependencies.
  • They make sure tools like linters and test runners work consistently (we'll discuss this more later).

Alongside isolated environments, a proper packaging tool is how you communicate the structure, metadata, and dependencies of your microservice.

Today we rely on the PEP 621 standard (https://peps.python.org/pep-0621/) that defines pyproject.toml file as the modern, canonical way to define specifications for a Python...

Introducing FastAPI

When building microservices, choosing the right web framework is essential. It should be lightweight yet robust, developer-friendly yet ready.

FastAPI perfectly fits this balance. FastAPI is a modern, high-performance web framework for building APIs with Python, relying on standard Python type hints.

It is designed from the ground up to support asynchronous programming, automatic OpenAPI documentation, and rapid execution powered by Starlette and Pydantic.

In this section, you will build your first endpoint with FastAPI and explore some of the core concepts that make FastAPI not only convenient but also an ideal framework for microservice architectures.

FastAPI combines speed with an excellent developer experience. Here’s why it stands out:

  • Asynchronous-first design utilizing async / await syntax
  • Type hints drive validation, documentation, and support for major Integrated Development Environments (IDEs)
  • Automatic generation of OpenAPI (Swagger) and ReDoc documentation...

Creating the First Test

In microservice-based architectures, managing a collection of independent, communicating services makes automated testing essential and unit tests are the first line of defense against regressions, integration bugs, and broken APIs.

They empower you to iterate with confidence, ensuring that existing behavior continues to work every time you run your code.

Why test? Here are a few good reasons:

  • Validate behavior: Confirm that your endpoints return the expected results
  • Detect regressions early: Prevent future changes from breaking existing logic
  • Enable refactoring: Refactor code with the assurance that nothing else is affected
  • Document expectations: Tests serve as executable specifications

For microservices, where interdependencies can be subtle and breaking changes potentially disastrous, maintaining a reliable suite of tests is critical, making it a wise investment to set up your test environment from the start.

Within the Python ecosystem, the pytest framework...

Setting up Formatters Linters, and Static Type Checkers

In coding, clarity, maintainability, and predictability are essential. When multiple developers work across many services, it's crucial that anyone can quickly understand, test, and modify the code with confidence. The simplest way to enable this is by enforcing consistent coding standards through automated tools.

This section introduces the essential tools every Python project should use: a formatter, an import sorter, a linter, and a static type checker. These tools will be added to your project as development dependencies and configured so they can be used manually, through your editor, or in a Continuous Integration (CI) pipeline.

Throughout this book, we will use Ruff for formatting, imports sorting, and linting. To add the ruff package as a development dependency, run:

uv add ruff --dev

Ruff can both check and format your code, ensuring it complies with your chosen rules. By default, the line length is set to 88 characters...

Overview of other Package Manager tools

We have used uv and will use it for the rest of the book to create projects, handling dependencies, running commands, etc.

However, Python has a rich, though sometimes confusing, ecosystem of tools to manage packages and environments.

This section introduces the most commonly used ones, helping you understand where each shines and how to get started.

pip + venv

pip is the default package manager while venv is the default library to manage a virtual environment that comes with the built-in Python distribution.

Their combination is the most basic method to manage environments and packages available in every Python 3 installation. To use it, you simply need to have Python installed on your machine.

The venv module creates isolated environments, while the pip command installs packages within them. Being built-in, this approach remains a reliable option for creating simple scripts or prototyping. It provides full control and transparency since it does...

Summary

Throughout this chapter, we have explored essential concepts related to microservices, kickstarted a service using uv, and built our first FastAPI endpoint. We also examined supporting development tools and took a comprehensive look at the evolving Python package management ecosystem.

By mastering these skills, you are now equipped to streamline project setup, enhance collaboration, and avoid common dependency pitfalls—key competencies for any Python developer aiming for efficient, maintainable codebases.

With these fundamentals in place, we are ready to move forward and begin building a more interactive application that handles request parameters and cookies in the next chapter.

Further reading

The definition of microservice is not unique.

For everything related to FastAPI, have a look at the official documentation:

For each of the package manager tools, refer to their respective documentation link:

Left arrow icon Right arrow icon

Key benefits

  • Design clear, evolvable services, and explain decisions your team trusts
  • Ship reliable backends with the right data stores, async jobs, auth, testing, and observability
  • Add practical AI features (RAG, agents) that reduces support and drives measurable value

Description

This book shows you how to turn an idea into a reliable product. This is a playbook for practical progress. Choose what to ship now, what to delay, and how to avoid risky changes. Keep services tidy, naming clear, and tests small but useful. You will build a realistic end-to-end system step by step, following the evolution of a babysitting marketplace platform with sign-up, search, booking, messaging, and payments delivered in steady increments. When it is time to add intelligence, you learn practical ways to use AI for customer support, recommendations, and operational insights. The focus stays on measurable value, not hype, while keeping performance, costs, and reliability predictable in production. Your guides are Giunio De Luca, PhD, author of Packt’s FastAPI Cookbook and an architect who has shipped systems across research, sports, and energy, and Igor “Benav” Magalhães, founder of Benav Labs and maintainer of widely used open-source tools. They share patterns they rely on when deadlines are real and reliability matters. By the end, you will not just know FastAPI. You will think like a senior engineer, plan delivery with confidence, avoid common traps, measure what matters, and run a backend platform that users trust and teams enjoy maintaining.

Who is this book for?

For Python developers who want to move beyond monoliths and ship scalable backends. Ideal for engineers aiming for lead/architect roles who need practical patterns for clean code, async workflows, and multi-database design. You’ll learn how to add secure authentication, real-time features, and AI capabilities RAG chat, agents, and analytics without losing testability or performance. Basic Python and web API knowledge is recommended.

What you will learn

  • Set up a microservice from scratch with modern Python tooling
  • Build RESTful APIs with clean boundaries, DI, and type-safe models
  • Design multiple services and compose them through a gateway
  • Model data with PostgreSQL, MongoDB, and vector stores
  • Scale with async I/O, background tasks, queues, and WebSockets
  • Secure services with OAuth2/JWT and role-based access
  • Test, profile, observe, and deploy with confidence
  • Add AI features including RAG chatbots, agents, and analytics
Estimated delivery fee Deliver to United States

Economy delivery 10 - 13 business days

Free $6.95

Premium delivery 6 - 9 business days

$21.95
(Includes tracking information)

Product Details

Country selected
Publication date, Length, Edition, Language, ISBN-13
Publication date : Jun 26, 2026
Length: 360 pages
Edition : 1st
Language : English
ISBN-13 : 9781835461167
Languages :
Tools :

What do you get with Print?

Product feature icon Instant access to your digital copy whilst your Print order is Shipped
Product feature icon Paperback book shipped to your preferred address
Product feature icon Redeem a companion digital copy on all Print orders
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
Modal Close icon
Payment Processing...
tick Completed

Shipping Address

Billing Address

Shipping Methods
Estimated delivery fee Deliver to United States

Economy delivery 10 - 13 business days

Free $6.95

Premium delivery 6 - 9 business days

$21.95
(Includes tracking information)

Product Details

Publication date : Jun 26, 2026
Length: 360 pages
Edition : 1st
Language : English
ISBN-13 : 9781835461167
Languages :
Tools :

Packt Subscriptions

See our plans and pricing
Modal Close icon
$19.99 billed monthly
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Simple pricing, no contract
$199.99 billed annually
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts
$279.99 billed in 18 months
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts

Table of Contents

4 Chapters
Welcome to Packt Early Access Chevron down icon Chevron up icon
Chapter 1: Launching the Platform: FastAPI Project Basics Chevron down icon Chevron up icon
Chapter 2: Creating the Parents’ Portal Chevron down icon Chevron up icon
Chapter 4: Dependency Injection in FastAPI Chevron down icon Chevron up icon
Get free access to Packt library with over 7500+ books and video courses for 7 days!
Start Free Trial

FAQs

What is the digital copy I get with my Print order? Chevron down icon Chevron up icon

When you buy any Print edition of our Books, you can redeem (for free) the eBook edition of the Print Book you’ve purchased. This gives you instant access to your book when you make an order via PDF, EPUB or our online Reader experience.

What is the delivery time and cost of print book? Chevron down icon Chevron up icon

Shipping Details

USA:

'

Economy: Delivery to most addresses in the US within 10-15 business days

Premium: Trackable Delivery to most addresses in the US within 3-8 business days

UK:

Economy: Delivery to most addresses in the U.K. within 7-9 business days.
Shipments are not trackable

Premium: Trackable delivery to most addresses in the U.K. within 3-4 business days!
Add one extra business day for deliveries to Northern Ireland and Scottish Highlands and islands

EU:

Premium: Trackable delivery to most EU destinations within 4-9 business days.

Australia:

Economy: Can deliver to P. O. Boxes and private residences.
Trackable service with delivery to addresses in Australia only.
Delivery time ranges from 7-9 business days for VIC and 8-10 business days for Interstate metro
Delivery time is up to 15 business days for remote areas of WA, NT & QLD.

Premium: Delivery to addresses in Australia only
Trackable delivery to most P. O. Boxes and private residences in Australia within 4-5 days based on the distance to a destination following dispatch.

India:

Premium: Delivery to most Indian addresses within 5-6 business days

Rest of the World:

Premium: Countries in the American continent: Trackable delivery to most countries within 4-7 business days

Asia:

Premium: Delivery to most Asian addresses within 5-9 business days

Disclaimer:
All orders received before 5 PM U.K time would start printing from the next business day. So the estimated delivery times start from the next day as well. Orders received after 5 PM U.K time (in our internal systems) on a business day or anytime on the weekend will begin printing the second to next business day. For example, an order placed at 11 AM today will begin printing tomorrow, whereas an order placed at 9 PM tonight will begin printing the day after tomorrow.


Unfortunately, due to several restrictions, we are unable to ship to the following countries:

  1. Afghanistan
  2. American Samoa
  3. Belarus
  4. Brunei Darussalam
  5. Central African Republic
  6. The Democratic Republic of Congo
  7. Eritrea
  8. Guinea-bissau
  9. Iran
  10. Lebanon
  11. Libiya Arab Jamahriya
  12. Somalia
  13. Sudan
  14. Russian Federation
  15. Syrian Arab Republic
  16. Ukraine
  17. Venezuela
What is custom duty/charge? Chevron down icon Chevron up icon

Customs duty are charges levied on goods when they cross international borders. It is a tax that is imposed on imported goods. These duties are charged by special authorities and bodies created by local governments and are meant to protect local industries, economies, and businesses.

Do I have to pay customs charges for the print book order? Chevron down icon Chevron up icon

The orders shipped to the countries that are listed under EU27 will not bear custom charges. They are paid by Packt as part of the order.

List of EU27 countries: www.gov.uk/eu-eea:

A custom duty or localized taxes may be applicable on the shipment and would be charged by the recipient country outside of the EU27 which should be paid by the customer and these duties are not included in the shipping charges been charged on the order.

How do I know my custom duty charges? Chevron down icon Chevron up icon

The amount of duty payable varies greatly depending on the imported goods, the country of origin and several other factors like the total invoice amount or dimensions like weight, and other such criteria applicable in your country.

For example:

  • If you live in Mexico, and the declared value of your ordered items is over $ 50, for you to receive a package, you will have to pay additional import tax of 19% which will be $ 9.50 to the courier service.
  • Whereas if you live in Turkey, and the declared value of your ordered items is over € 22, for you to receive a package, you will have to pay additional import tax of 18% which will be € 3.96 to the courier service.
How can I cancel my order? Chevron down icon Chevron up icon

Cancellation Policy for Published Printed Books:

You can cancel any order within 1 hour of placing the order. Simply contact customercare@packt.com with your order details or payment transaction id. If your order has already started the shipment process, we will do our best to stop it. However, if it is already on the way to you then when you receive it, you can contact us at customercare@packt.com using the returns and refund process.

Please understand that Packt Publishing cannot provide refunds or cancel any order except for the cases described in our Return Policy (i.e. Packt Publishing agrees to replace your printed book because it arrives damaged or material defect in book), Packt Publishing will not accept returns.

What is your returns and refunds policy? Chevron down icon Chevron up icon

Return Policy:

We want you to be happy with your purchase from Packtpub.com. We will not hassle you with returning print books to us. If the print book you receive from us is incorrect, damaged, doesn't work or is unacceptably late, please contact Customer Relations Team on customercare@packt.com with the order number and issue details as explained below:

  1. If you ordered (eBook, Video or Print Book) incorrectly or accidentally, please contact Customer Relations Team on customercare@packt.com within one hour of placing the order and we will replace/refund you the item cost.
  2. Sadly, if your eBook or Video file is faulty or a fault occurs during the eBook or Video being made available to you, i.e. during download then you should contact Customer Relations Team within 14 days of purchase on customercare@packt.com who will be able to resolve this issue for you.
  3. You will have a choice of replacement or refund of the problem items.(damaged, defective or incorrect)
  4. Once Customer Care Team confirms that you will be refunded, you should receive the refund within 10 to 12 working days.
  5. If you are only requesting a refund of one book from a multiple order, then we will refund you the appropriate single item.
  6. Where the items were shipped under a free shipping offer, there will be no shipping costs to refund.

On the off chance your printed book arrives damaged, with book material defect, contact our Customer Relation Team on customercare@packt.com within 14 days of receipt of the book with appropriate evidence of damage and we will work with you to secure a replacement copy, if necessary. Please note that each printed book you order from us is individually made by Packt's professional book-printing partner which is on a print-on-demand basis.

What tax is charged? Chevron down icon Chevron up icon

Currently, no tax is charged on the purchase of any print book (subject to change based on the laws and regulations). A localized VAT fee is charged only to our European and UK customers on eBooks, Video and subscriptions that they buy. GST is charged to Indian customers for eBooks and video purchases.

What payment methods can I use? Chevron down icon Chevron up icon

You can pay with the following card types:

  1. Visa Debit
  2. Visa Credit
  3. MasterCard
  4. PayPal
What is the delivery time and cost of print books? Chevron down icon Chevron up icon

Shipping Details

USA:

'

Economy: Delivery to most addresses in the US within 10-15 business days

Premium: Trackable Delivery to most addresses in the US within 3-8 business days

UK:

Economy: Delivery to most addresses in the U.K. within 7-9 business days.
Shipments are not trackable

Premium: Trackable delivery to most addresses in the U.K. within 3-4 business days!
Add one extra business day for deliveries to Northern Ireland and Scottish Highlands and islands

EU:

Premium: Trackable delivery to most EU destinations within 4-9 business days.

Australia:

Economy: Can deliver to P. O. Boxes and private residences.
Trackable service with delivery to addresses in Australia only.
Delivery time ranges from 7-9 business days for VIC and 8-10 business days for Interstate metro
Delivery time is up to 15 business days for remote areas of WA, NT & QLD.

Premium: Delivery to addresses in Australia only
Trackable delivery to most P. O. Boxes and private residences in Australia within 4-5 days based on the distance to a destination following dispatch.

India:

Premium: Delivery to most Indian addresses within 5-6 business days

Rest of the World:

Premium: Countries in the American continent: Trackable delivery to most countries within 4-7 business days

Asia:

Premium: Delivery to most Asian addresses within 5-9 business days

Disclaimer:
All orders received before 5 PM U.K time would start printing from the next business day. So the estimated delivery times start from the next day as well. Orders received after 5 PM U.K time (in our internal systems) on a business day or anytime on the weekend will begin printing the second to next business day. For example, an order placed at 11 AM today will begin printing tomorrow, whereas an order placed at 9 PM tonight will begin printing the day after tomorrow.


Unfortunately, due to several restrictions, we are unable to ship to the following countries:

  1. Afghanistan
  2. American Samoa
  3. Belarus
  4. Brunei Darussalam
  5. Central African Republic
  6. The Democratic Republic of Congo
  7. Eritrea
  8. Guinea-bissau
  9. Iran
  10. Lebanon
  11. Libiya Arab Jamahriya
  12. Somalia
  13. Sudan
  14. Russian Federation
  15. Syrian Arab Republic
  16. Ukraine
  17. Venezuela
Modal Close icon
Modal Close icon