Deploy your FastAPI app to Heroku
Step-by-step deployment help for FastAPI apps on Heroku. We fix FastAPI-specific deployment issues, configure Heroku, and get your app live. From $19.
FastAPI issues we fix before deploying
Common FastAPI problems that affect Heroku deployments.
Blocking calls inside async endpoints
Synchronous database calls, file operations, or HTTP requests inside async def endpoints block the entire event loop, making your API unresponsive under load.
Missing authentication on endpoints
API routes that handle sensitive data or actions without any auth middleware — Depends() for authentication is simply not included in the route definition.
No CORS configuration
CORSMiddleware either missing (blocking all cross-origin requests) or set to allow_origins=['*'] (allowing any website to call your API).
Pydantic models without validation constraints
Request models that accept any string length, any number range, and any format. No Field() constraints, so invalid data flows through your system.
Heroku deployment issues we check for
Common Heroku problems that break FastAPI apps in production.
Free dyno sleeping causes cold starts
Eco and Basic dynos sleep after 30 minutes of inactivity. AI-generated apps with webhook receivers or background jobs break when the dyno is asleep.
Ephemeral filesystem loses uploaded files
AI tools save user uploads and generated files to the local filesystem, but Heroku's ephemeral FS wipes all changes on every dyno restart or deploy.
Database connection pool exhaustion
Heroku Postgres plans have strict connection limits (20 on Hobby). AI-generated apps open a new connection per request, exhausting the pool under moderate traffic.
Procfile missing or incorrect
AI-generated projects lack a Procfile, causing Heroku to guess the start command. For non-standard setups, this guess is often wrong.
Start with a self-serve audit
Get a professional review of your FastAPI project before deploying to Heroku.
External Security Scan
Black-box review of your public-facing app. No code access needed.
- OWASP Top 10 vulnerability check
- SSL/TLS configuration analysis
- Security header assessment
- Expert review within 24h
Code Audit
In-depth review of your source code for security, quality, and best practices.
- Security vulnerability analysis
- Code quality review
- Dependency audit
- Architecture review
- Expert + AI code analysis
Complete Bundle
Both scans in one package with cross-referenced findings.
- Everything in both products
- Cross-referenced findings
- Unified action plan
100% credited toward any paid service. Start with an audit, then let us fix what we find.
How it works
Tell us about your app
Share your project details and what you need help with.
Expert + AI audit
A human expert assisted by AI reviews your code within 24 hours.
Launch with confidence
We fix what needs fixing and stick around to help.
Frequently asked questions
How do I deploy a FastAPI app to Heroku?
We handle FastAPI deployments to Heroku end to end. Start with our code audit ($19) to identify deployment blockers specific to your FastAPI project, then we configure Heroku, fix issues, and get your app live in production.
What FastAPI issues affect Heroku deployments?
FastAPI projects commonly have blocking calls inside async endpoints and missing authentication on endpoints. On Heroku, these combine with free dyno sleeping causes cold starts and ephemeral filesystem loses uploaded files to cause deployment failures.
Can SpringCode deploy my FastAPI project to Heroku?
Yes. We specialize in deploying FastAPI applications to Heroku. We audit your codebase for FastAPI-specific issues, configure Heroku correctly, and handle the full deployment so your app runs reliably in production.
What does FastAPI deployment to Heroku cost?
Our code audit ($19) identifies all Heroku deployment blockers in your FastAPI project. Full deployment assistance is scoped with a fixed quote after the audit — no hourly billing or surprise charges.
Related resources
Other techs on Heroku
Deploy FastAPI elsewhere
Need help deploying FastAPI to Heroku?
Tell us about your project. We'll respond within 24 hours with a clear plan and fixed quote.