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Serverless VS FastAPI

Compare Serverless VS FastAPI and see what are their differences

Serverless logo Serverless

Toolkit for building serverless applications

FastAPI logo FastAPI

FastAPI is an Open Source, modern, fast (high-performance), web framework for building APIs with Python 3.6+ based on standard Python type hints.
  • Serverless Landing page
    Landing page //
    2023-08-06
  • FastAPI Landing page
    Landing page //
    2023-05-14

Serverless features and specs

  • Scalability
    Serverless architectures can automatically scale up or down based on the traffic, without the need for manual intervention.
  • Cost Efficiency
    You only pay for what you use. There are no expenses for idle times because billing is based on the actual amount of resources consumed by your application.
  • Reduced Maintenance
    No need to manage, patch, update, or monitor servers. This allows focus on writing code and deploying features.
  • Speed of Development
    Serverless platforms provide built-in integration with other services, which makes it quicker to develop and deploy applications.
  • High Availability
    Serverless platforms typically offer high availability and fault tolerance out of the box, reducing the risk of downtime.

Possible disadvantages of Serverless

  • Cold Start Latency
    Serverless functions can suffer from higher latency during initial invocation or when they havenโ€™t been used for a while.
  • Limited Execution Time
    Most serverless platforms impose a maximum execution time limit on functions, which may not be suitable for long-running applications.
  • Vendor Lock-In
    Serverless architectures often rely on the specific features and services of a cloud provider, which can make it difficult to switch providers.
  • Complexity in Debugging
    Debugging and monitoring serverless applications can be more challenging compared to traditional architectures, due to their distributed and ephemeral nature.
  • Security Concerns
    Sharing resources on a serverless platform can introduce security vulnerabilities that must be managed vigilantly.

FastAPI features and specs

  • High Performance
    Built on Starlette and Pydantic, FastAPI is one of the fastest frameworks for Python, providing high performance due to its asynchronous request handling.
  • Automatic Interactive API Documentation
    FastAPI automatically generates interactive API documentation via Swagger UI and ReDoc, which are very helpful for development and testing.
  • Type Checking and Validation
    With Pydantic models and Python type hints, FastAPI provides automatic data validation and type checking, reducing the chance of runtime errors.
  • Ease of Use
    Its syntax and design make it easy to learn for Python developers, offering a smooth development experience while reducing boilerplate code.
  • Asynchronous Support
    FastAPI supports asynchronous programming, allowing for better performance for I/O-bound operations, making it optimal for handling many simultaneous connections.
  • Extensive Documentation
    It has comprehensive and well-structured documentation, which is very useful for both beginners and advanced users.
  • Community and Ecosystem
    FastAPI has a growing community and ecosystem, with many plugins and integrations available to extend its functionality.

Possible disadvantages of FastAPI

  • Learning Curve for Asynchronous Programming
    Although FastAPI itself is easy to learn, grasping the concepts of asynchronous programming in Python can be challenging for beginners.
  • Complex Dependencies
    Using Pydantic for advanced validation can make the request models complex, requiring a deeper understanding of Pydantic and its functionalities.
  • Early Stage Libraries
    Some third-party libraries and extensions specifically tailored for FastAPI might still be in early stages of development and lack long-term stability.
  • Limited Real-World Examples
    Although the documentation is extensive, there might be limited real-world examples and case studies readily available compared to more mature frameworks.
  • Deployment Complexity
    Deploying FastAPI applications might be more complex in comparison to traditional synchronous frameworks, mainly due to the need for asynchronous server setups.

Analysis of Serverless

Overall verdict

  • Serverless is a good choice for developers who want to focus more on writing code rather than managing servers. It is well-suited for scenarios where scalability, cost-efficiency, and rapid deployment are critical. However, it might not be the best option for applications with high execution duration or complex dependencies that require low-latency network access or specialized hardware.

Why this product is good

  • Serverless (provided by serverless.com) is a popular framework for building applications that leverage serverless architecture, which eliminates the need for server management and minimizes overhead. It allows developers to deploy functions without worrying about the underlying infrastructure, scaling automatically according to demand. This streamlines the deployment process, reduces operational costs, and accelerates development timelines.

Recommended for

  • Startups and small businesses looking to minimize infrastructure costs.
  • Developers focusing on microservices and event-driven architectures.
  • Teams needing rapid prototyping and development cycles.
  • Applications with variable workloads and unpredictable traffic patterns.

Analysis of FastAPI

Overall verdict

  • FastAPI is widely regarded as a good choice, especially for applications that require high performance, scalability, and modern Python features. It is suitable for both simple and complex projects, making it a versatile tool in the web development ecosystem.

Why this product is good

  • FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.7+ based on standard Python type hints. It is built on top of Starlette for web framework capabilities and Pydantic for data validation and settings management. FastAPI is known for its excellent performance, automatic generation of interactive API documentation (with Swagger and Redoc), and support for asynchronous programming. Developers appreciate its ease of use, detailed documentation, and helpful error messages.

Recommended for

  • Developers building RESTful APIs
  • Teams looking for a high-performance ASGI-based web framework
  • Projects that require asynchronous programming capabilities
  • Applications needing automatic generation of interactive API documentation
  • Python developers who prefer utilizing type hints for code clarity and validation

Serverless videos

Thoughts on Zero V3, Instant Page and Serverless 1.37!

FastAPI videos

FastAPI from the ground up

More videos:

  • Tutorial - 30 Days of Python - Day 14 - Web App with Flask, FastAPI, ngrok, and Invictify - Python TUTORIAL
  • Review - [PT] Python - API com FastAPI - Chat | twitch.tv/codeshow

Category Popularity

0-100% (relative to Serverless and FastAPI)
Developer Tools
15 15%
85% 85
Open Source
100 100%
0% 0
API Tools
0 0%
100% 100
Cloud Computing
100 100%
0% 0

User comments

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Reviews

These are some of the external sources and on-site user reviews we've used to compare Serverless and FastAPI

Serverless Reviews

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FastAPI Reviews

  1. Kurslog team
    ยท Working at Kurslog ยท

    When our backend team needs to build services for data parsing, aggregators, or high-load APIs, FastAPI is our absolute go-to choice. It completely lives up to its name-development speed is outstanding.

    The combination of Pydantic for data validation and built-in async support keeps our shared codebase clean, strictly typed, and reliable. But the biggest highlight for our cross-functional team is the automatic generation of interactive OpenAPI (Swagger) documentation. Our frontend and mobile developers no longer have to wait for backend engineers to manually update API docs; everything stays perfectly in sync automatically. It has drastically improved our team's communication and delivery speed.

    ๐Ÿ Competitors: Django, Flask, ExpressJS, Nest.js, Spring Boot
    ๐Ÿ‘ Pros:    Blazing fast performance (on par with nodejs and go)|Native asynchronous support out of the box|Automatic, interactive documentation generation (swagger/redoc)|Strict typing and data validation with pydantic
    ๐Ÿ‘Ž Cons:    Smaller plug-and-play ecosystem compared to older frameworks like django|Requires our architects to design the project structure and directory layout from scratch

The 20 Best Laravel Alternatives for Web Development
FastAPI, as the name hints, is a swift mover. Built on Starlette, itโ€™s all about speed and performance with Python. Crafting API masterpieces at the speed of light, now thatโ€™s something.
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Since its release in 2018, it has rapidly gained popularity due to its great performance and simplicity. In fact, according to PyPi Stats, FastAPI has over 9 million monthly downloads, surpassing even full-stack frameworks like Django.
Source: kinsta.com
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myapp/ is the main directory of your FastAPI application. It includes all the other files and directories needed for the application.static/ is a directory used to store static assets such as CSS, JavaScript, and image files. These assets are served directly by the web server and are typically used to add visual styling and interactivity to the application.css/, img/, js/...
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FastAPI Alternative โ€“ So many alternatives app to FastAPI that you must to know out there. And, looking for an ideal software was not easy matter. Lucky you, at this page you can find the best replacement app for FastAPI. So what you are waiting for, get the latest FastAPI alternative app for Windows 10 from this page.
Top 5 Back-End Frameworks to Consider for Web Development in 2021
FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.6+ based on standard Python type hints. It is fast when compared to other major Python frameworks like Flask and Django. FastAPI gives great flexibility to fulfill businessesโ€™ API needs in todayโ€™s evolving world.

Social recommendations and mentions

Based on our record, FastAPI should be more popular than Serverless. It has been mentiond 312 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

Serverless mentions (39)

  • Show HN: Winglang โ€“ a new Cloud-Oriented programming language
    GP may have been referring to Serverless Framework (http://serverless.com//). - Source: Hacker News / over 2 years ago
  • Invocation error - can't find any results helping me to solve this issue
    I deployed a lambda and http api gateway using a serverless.com (sls) template as a start. I get the following error when it processes a specific request:. Source: almost 3 years ago
  • Deploying Lambdas from Zipped Code on S3 vs Image Repository
    Have you tried serverless.com ? It lets you have infrastructure as code. Source: over 3 years ago
  • [p] I built an open source platform to deploy computationally intensive Python functions as serverless jobs, with no timeouts
    - With Lambda, you manage creating and building the container yourself, as well as updating the Lambda function code. There are tools out there such as sst or serverless.com which help streamline this. Source: over 3 years ago
  • AWS Lambda, a good host for a rest API?
    If you'd like to use Lambda, usually you need to engineer FOR it, from day one, you don't (often) get to choose some other framework and shoehorn it into Lambda and Serverless. There's some great frameworks to help deploy code into Lambda easily and create REST endpoints for things, one such frameworks is serverless.com that helps easily deploy to it, but it lacks a framework for doing REST that also supports... Source: over 3 years ago
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FastAPI mentions (312)

  • I Built My First Machine Learning API โ€” Here's Everything I Learned
    I used FastAPI, a Python framework built specifically for creating APIs quickly, with automatic validation and interactive documentation baked in. - Source: dev.to / 8 days ago
  • Shipping Sovereign SDK: Cryptographic Forensic Receipts and the End of the AI "Prose Tax"
    The Sovereign SDK is a Python-native framework designed to minimize prose overhead while generating ironclad, cryptographic execution receipts for AI agents, complete with drop-in FastAPI/Starlette ASGI middleware. - Source: dev.to / 3 months ago
  • 5-Minute AI Jobs and Closed Tabs โ€” Why We Built Replay-Then-Tail SSE
    We had a feature in production where a single user request could run for five-plus minutes โ€” fetch documents, chunk them, hit an LLM per chunk, synthesize a final answer. We did the obvious thing first: a FastAPI handler that ran the pipeline and streamed progress back to the browser over Server-Sent Events. - Source: dev.to / 4 months ago
  • FastAPI With LangChain and MongoDB
    FastAPI is a Python framework for building APIs quickly, efficiently, and with very little code. - Source: dev.to / 4 months ago
  • I Built A " CrowdSense AI " : A Scalable, Context-Aware Platform for Smart Stadiums
    Backend: Python-based FastAPI for its asynchronous I/O capabilities and rapid JSON serialization. - Source: dev.to / 4 months ago
View more

What are some alternatives?

When comparing Serverless and FastAPI, you can also consider the following products

SST - Work on your serverless apps live

Flask - a microframework for Python based on Werkzeug, Jinja 2 and good intentions.

CTO.ai - Build, share & run developer workflows in the CLI + Slack

ExpressJS - Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple

AWS Lambda - Automatic, event-driven compute service

Django - The Web framework for perfectionists with deadlines