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FastAPI VS Theysaid

Compare FastAPI VS Theysaid and see what are their differences

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.

Rating
5.0 · 1 review
Pricing
Open source Free
Alternatives Is it good?
Theysaid

Conversational AI surveys, interviews, user tests, polls

Rating
0 reviews
Pricing
Free trial $49 / Monthly ("Essential" "1 seat license" "1 Active AI project")
Alternatives Is it good?
RepDB
Exercise dataset for fitness apps: transparent background, animations, no subscription sponsored
Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

Which is more popular?

Based on our record, FastAPI seems to be more popular. It has been mentioned 312 times since March 2021.

social mentions
312 vs 0
Developer Tools popularity
100% vs 0%
alternatives listed
240+ vs 230

Base details

Website, pricing, platforms and company facts side by side.

FastAPI
Theysaid
Website fastapi.tiangolo.com theysaid.io
Pricing
Open source Free
Free trial $49 / Monthly ("Essential" "1 seat license" "1 Active AI project") Official pricing
Company Startup from Colombia Startup from the United States · 20 - 49 employees
Listed in
Developer Tools API Tools Python Programming Web Frameworks Python Web Framework +2
AI Surveys Forms And Surveys Customer Feedback Form Builder Conversational AI Survey Tools User Feedback Chatbots +6

About FastAPI and Theysaid

In their own words, as submitted to SaaSHub.

FastAPI
Theysaid

No description of FastAPI yet.

TheySaid - The everything app for feedback, powered by AI and voice to gather, analyze, and act on feedback. Conduct interviews, user tests, surveys, polls, and funnel results into a single dashboard or your database via integrations. Popular use cases include onboarding, customer + employee...

Read more about Theysaid

Features and specs

What each product offers, as listed by its team.

FastAPI 7 features
Theysaid 13 features
  • 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

  • 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.
  • AI Surveys
    Conversational AI surveys that dig deeper to uncover the why behind every answer.
  • AI Interviews
    AI conducts adaptive interviews, asking smarter questions and adjusting in real time to uncover deeper insights.
  • 2-way voice
    Users speak to AI and complete their form with voice while AI reads questions aloud.
  • Usability Testing
    Ask users to do tasks, visit websites or prototypes, and get voice and video recordings.
  • AI Sidebar
    AI tells you what you've learned recently, suggests new projects, and answers questions.
  • AI Forms
    Now forms are beautiful with an optional AI assist mode to help users quickly fill out forms.
  • Conditional Logic
    Simple, intuitive branching logic still allows AI to ask follow-up questions.
  • Panel Recruiting
    Recruit feedback participants from our panel integrations, or bring your own panel.
  • Teach AI
    Give AI context about your company, pricing, and product by uploading any document.
  • Integrations
    Full-featured connectors with HubSpot, Salesforce, Slack, and more.
  • Free survey creator
    On the website, you can create or brainstorm your next project and then add it to your account.
  • Import surveys
    Import surveys from your ancient survey tools like Qualtrics, SurveyMonkey, or Typeform.
  • Templates
    The best templates for popular feedback types are available with one click.

Analysis

An editorial look at what each product does well and who it suits.

FastAPI
Theysaid

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

Overall verdict

  • TheySaid (theysaid.io) is a solid AI-powered survey and feedback platform that uses conversational, interactive surveys to gather deeper customer insights than traditional static forms, making it a good choice for teams focused on customer experience and product feedback.

Why this product is good

  • Uses AI-driven conversational surveys that feel more like a dialogue, encouraging higher response rates and richer qualitative feedback
  • Automatically follows up on responses to dig deeper into customer sentiment without manual effort
  • Provides AI-generated summaries and actionable insights, saving teams time in analyzing feedback
  • Easy to set up and deploy surveys across multiple touchpoints such as websites, emails, and products
  • Helps uncover the 'why' behind customer opinions rather than just collecting surface-level ratings

Recommended for

  • Product teams seeking qualitative user feedback to guide roadmap decisions
  • Customer success and experience teams measuring satisfaction and reducing churn
  • SaaS companies wanting to gather in-app feedback conversationally
  • Marketing teams looking for deeper audience insights beyond standard surveys
  • Small to mid-sized businesses that want AI-assisted feedback analysis without heavy manual work

Videos

Walkthroughs and reviews on video.

FastAPI 3 videos + Add
Theysaid 2 videos + Add

FastAPI from the ground up

More videos

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

TheySaid 3.0 Review – AI Customer Feedback Analysis & Voice-of-Customer Platform (2025)

More videos

  • - Customer Survey Tool product review | Theysaid AI

Category popularity

How often each product is chosen within a category, 0–100% relative to the other.

Score bands 0–20 21–40 41–50 51–60 61–100
FastAPI
Theysaid
100% 100%
Developer Tools
0% 0%
0% 0%
Customer Feedback
100% 100%
100% 100%
API Tools
0% 0%
0% 0%
AI
100% 100%

Questions & Answers

As answered by people managing FastAPI and Theysaid.

What makes your product unique?

Theysaid's answer:

Most surveys are dull and only scratch the surface. TheySaid turns surveys into conversations, asking real-time follow-ups, revealing the why behind every answer. This gives revenue leaders sharper visibility into customer needs, fueling faster, more confident business decisions that drive growth.

Why should a person choose your product over its competitors?

Theysaid's answer:

Most survey tools stop at collecting answers, giving leaders surface-level data that’s hard to act on. TheySaid turns feedback into real conversations with smart follow-ups, capturing the why behind customer behavior. This means revenue leaders don’t just get data, they get clear action items: what to improve, where to double down, and how to reduce churn. And with insights delivered 10x faster, they can act quickly to capture growth opportunities and make confident business decisions.

How would you describe the primary audience of your product?

Theysaid's answer:

TheySaid is built for B2B leaders who rely on customer insights to drive growth. Our primary audience includes Customer Success teams, Revenue leaders, Product managers, and Marketing executives at SaaS and subscription-based businesses. They use TheySaid to uncover authentic customer sentiment, strengthen retention, and identify expansion opportunities.

What's the story behind your product?

Theysaid's answer:

Surveys were dead. Customers ignored them, response rates tanked, and leaders were left making decisions on scraps of data. Lihong Hicken and Chris Hicken saw the gap and built TheySaid, the first AI-powered conversational survey that actually listens. With AI interviews, live polls, and user testing alongside surveys, TheySaid captures the why behind every answer and instantly translates insights into clear action items. For revenue leaders, that means faster decisions, smarter growth moves, and insights delivered 10x quicker than any traditional tool.

Which are the primary technologies used for building your product?

Theysaid's answer:

TheySaid leverages advanced AI (natural language processing, machine learning, and generative AI), cloud infrastructure, and secure integrations with popular CRM and HR systems to deliver fast, scalable, and reliable insights.

User comments

Share your experience with using FastAPI and Theysaid. For example, how are they different and which one is better?

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Reviews and articles

External articles and on-site reviews we used to compare the two products.

FastAPI 5.0 · 1 review
Theysaid no reviews yet
  • Rated 5/5 by Kurslog team
    SaaSHub review
    · Apr 2026

    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...

  • The 20 Best Laravel Alternatives for Web Development
    tms-outsource.com · Jan 2024

    FastAPI, as the name hints, is a swift mover. Built on Starlette, it’s all about speed and performance with Python. Crafting API masterpieces at the speed of light, now that’s something.

  • 25 Python Frameworks to Master
    kinsta.com · Oct 2023

    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...

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We have no reviews of Theysaid yet. Be the first one to post

Social recommendations and mentions

Recommendations tracked on public social media and blogs since March 2021.

FastAPI 312 mentions
Theysaid 0 mentions
  • I Built My First Machine Learning API — 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 / about 1 month 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 / 4 months ago
  • 5-Minute AI Jobs and Closed Tabs — Why We Built Replay-Then-Tail SSE
    We had a feature in production where a single user request could run for five-plus minutes — 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... - Source: dev.to / 5 months ago

View more

Tracking Theysaid since Aug 2024.

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