Project Critique for FastAPI

Anshu Pathak, Logan Butler, Tien DeLong-Headley

December 1, 2025

What is FastAPI overall?

• A Python tool for building web APIs.
• Uses Starlette for web handling and Pydantic for data checks.
• Type hints define what data an API accepts and returns.
• Designed to be fast, easy to learn, and good for both small and large projects.

How well documented is FastAPI?

Automatic Interactive Documentation

• The docs clearly show how API docs are created automatically.
• Examples are easy to follow but often stay basic.
• Pages mix “how to do it” with “what it is.”
• Doesn’t clearly explain when to use Swagger UI vs. ReDoc.
• Mentions some helpful features, but misses deeper explanation or real-world guidance.

High Performance

• Explains it’s on par with NodeJS and GO
• You have to click two separate links before getting to an explanation page
• Benchmarks are an outside website not on the actual FastAPI website.
• Lacks indepth explanation of why and how fast FastAPI actually is.

Dependency Injection

• Introduces the Depends() system as a simple way to declare reusable logic.
• Demonstrates how dependencies can handle tasks like authentication, database sessions, or common parameters.
• Explains that dependencies can be nested, allowing complex logic to be broken into smaller reusable pieces.
• Emphasizes that dependency injection keeps code modular, testable, and easier to maintain.
• No link to dependency section of documentation on features tab.

Critique of Overall Documentation Features and Layout

Strengths

• Strong reference documentation
  • Clear API signatures, parameters, defaults, and behavior.
  • Reliable for looking up low-level details.
• Beginner-friendly introductory material
  • Quickstart/tutorial content with runnable examples.
  • Clear demonstration through interactive docs.

Weaknesses (Diátaxis Misalignments)

• Blurring of documentation modes
  • Many pages mix tutorial, reference, and conceptual info.
  • Harder for readers to know what type of help a page provides.
• Limited “Explanation” content
  • Lacks deep discussion of architectural trade-offs or design philosophy
  • Makes advanced use harder to reason about.

Structural Gaps

• No “documentation map” guiding users to:
  • learn (tutorials)
  • do (how-tos)
  • understand (explanations)
  • look up (reference)
• Docs scale well for small projects, but guidance diminishes for large / complex systems.
• Real-world patterns and best practices are scattered instead of clearly organized.

Is FastAPI a Worthwhile Tool for Beginners?

Overall Assessment

• Yes—kind of.
  • The learning curve is gentle for small projects due to excellent beginner-oriented examples.
  • Type-hint-driven design gives immediate feedback and intuitive API creation.
  • The interactive docs make it easy for beginners to visualize results.

Benefits for Beginners

• Quick “first success”: build a working API in minutes.
• Automatic validation reduces trial-and-error.
• Clear, example-driven introductory material.

Challenges for Beginners

• As projects grow, beginners may struggle:
  • Fewer conceptual explanations for why things work the way they do.
  • Less guidance on project structure, testing strategies, deployment patterns.
• Beginners transitioning to intermediate users may find gaps in “How-to” style documentation.

Minor Comparison: FastAPI vs. Django Documentation

• Django has more mature Diátaxis structure:
  • Clear separation between tutorials, topic guides, reference, and how-tos.
  • Rich conceptual explanations (for things like tool architecture)
  • Strong real-world “how-tos”.

How FastAPI Differs

• FastAPI is easier to start with, but Django is easier to grow with.
• FastAPI’s docs favor code-first examples while Django’s favors structured learning.
• Django’s documentation ecosystem is extensive while FastAPI’s is still growing.

Overview of strengths of FastAPI docs

• Very clear and easy to read.
• Simple examples that work immediately.
• Built-in interactive API docs explained well.
• Good beginner-friendly introductions.
• Frequently updated and maintained.

Overview of weaknesses of FastAPI docs

• Some topics feel lightly explained.
• Advanced patterns lack clear guidance.
• Large-project advice is limited.
• Dependency system needs deeper examples.
• Sections sometimes mix concepts and tutorials.

Questions?