Use this checklist from API planning → development → deployment → maintenance.
This assumes i will use flask restful for the backend.

1. Planning & Requirements

API Definition

• Define project goal

• Define API consumers (Frontend, Mobile App, Third-party)

• Define MVP features

• Define future features (v2+)

• Define business requirements

• Identify external integrations

API Design

• List all resources/entities

• Define relationships between resources

• Design endpoints

• Define request payloads

• Define response structures

• Define status codes

• Define error responses

2. Architecture & Project Setup

Repository Setup

• Create GitHub repository

• Add README.md

• Add LICENSE (if needed)

• Configure branch strategy

Project Initialization

• Create project folder

• Create virtual environment

• Install Flask

• Install Flask-RESTful

• Install Flask-Migrate

• Install Flask-SQLAlchemy

• Install Flask-CORS

• Install python-dotenv

Git Setup

• Initialize Git

• Create .gitignore

• First commit

3. Project Structure

Recommended Structure

• app.py

• config.py

• models/

• resources/

• services/

• utils/

• validators/

• schemas/

• migrations/

• tests/

Configuration

• Development configuration

• Testing configuration

• Production configuration

• Environment variables

4. Database Design

Data Modeling

• Identify entities

• Define tables

• Define columns

• Define constraints

• Define indexes

• Define relationships

Database Setup

• Configure SQLAlchemy

• Create initial migration

• Apply migrations

• Seed development data

Validation

• Required fields

• Unique constraints

• Foreign key validation

5. API Development

CRUD Operations

• Create endpoints

• Read endpoints

• Update endpoints

• Delete endpoints

Request Handling

• Request validation

• Data sanitization

• JSON parsing

Response Handling

• Consistent response format

• Pagination

• Filtering

• Sorting

Pagination & Query Features

• Implement pagination
• Define page size limits
• Filtering
• Sorting
• Search functionality

6.Input Validation

Request Validation

• Validate request payloads
• Validate query parameters
• Validate path parameters
• Validate file uploads

Validation Tools

• Marshmallow
• Pydantic
• Custom validators

Error Responses

• Consistent validation errors
• Human-readable validation messages

7. Authentication & Authorization

Authentication

• User registration

• User login

• Password hashing

• JWT authentication

• Refresh tokens

Authorization

• Role-based access control

• Protected routes

• Admin permissions

8.CORS Configuration

Cross-Origin Access

• Configure allowed origins
• Configure allowed methods
• Configure allowed headers
• Configure credentials policy

Environment Rules

• Development origins
• Production origins

9. Security

API Security

• Validate all inputs

• Prevent SQL injection

• Prevent XSS

• Prevent mass assignment

• Limit exposed data

Secrets Management

• Store secrets in .env

• Ignore .env in Git

• Rotate sensitive credentials

Rate Limiting

• Configure rate limiting

• Protect login endpoints

• Protect public APIs

Headers

• Security headers

• CORS configuration

Request Protection

• Request size limits
• Upload size limits
• Brute-force protection

10. Error Handling

Error Responses

• Validation errors

• Authentication errors

• Authorization errors

• Database errors

• Server errors

Logging

• Application logs

• Error logs

• Security logs

Centralized Error Handling

• Global exception handlers
• Standardized error responses
• Custom exception classes
• Error logging integration

11. Testing

Unit Tests

• Model tests

• Service tests

• Utility tests

API Tests

• Endpoint tests

• Authentication tests

• Authorization tests

Coverage

• Generate coverage reports

• Verify critical paths

12. API Documentation

Documentation

• Endpoint descriptions

• Request examples

• Response examples

• Error examples

Swagger / OpenAPI

• Configure Swagger UI

• Generate OpenAPI specification

13. Performance

Database Performance

• Optimize queries

• Add indexes

• Prevent N+1 queries

API Performance

• Pagination

• Response optimization

• Compression

Caching

• Configure Redis
• Configure Flask-Caching
• Cache expensive queries
• Cache frequently accessed resources
• Define cache invalidation strategy

14.API Versioning

Version Strategy

• Define API versioning scheme
• Implement /api/v1 routes
• Plan for future versions
• Deprecation strategy

15. Background Tasks (Optional)

Task Queue

• Configure Celery

• Configure Redis

• Implement background jobs

Use Cases

• Email sending

• Report generation

• Scheduled tasks

15. Production Readiness

Cleanup

• Remove debug code

• Remove test credentials

• Remove unused endpoints

Configuration

• DEBUG=False

• Secure environment variables

• Production database configured

Build Verification

• Application starts successfully

• Database migrations succeed

• Health check endpoint works

Health Checks

• /health endpoint
• Database health checks
• Dependency health checks

16. Deployment

Infrastructure

• Select hosting provider

• Configure database server

• Configure environment variables

WSGI Server

• Install Gunicorn

• Configure Gunicorn

Reverse Proxy

• Configure Nginx

• Configure HTTPS

Deployment Verification

• Test API endpoints

• Verify logs

• Verify database connectivity

17. Monitoring

Monitoring

• Application monitoring

• Error monitoring

• Performance monitoring

• Uptime monitoring

Metrics

• Response times

• Error rates

• Database performance

Observability

• Structured logging
• Request tracing
• Correlation IDs
• Performance metrics

18. CI/CD

GitHub Actions

• Run linting

• Run tests

• Run security checks

Deployment Automation

• Automatic deployments

• Deployment rollback strategy

Security Automation

• Dependency vulnerability scanning
• Secret scanning
• Automated security checks

19. Maintenance

Ongoing Tasks

• Update dependencies

• Apply security patches

• Review logs

• Optimize slow queries

• Improve test coverage

• Backup database

• Verify disaster recovery plan

Launch Checklist

• All endpoints tested

• Authentication working

• Authorization verified

• Validation implemented

• Logging enabled

• API documentation complete

• HTTPS enabled

• Database backups configured

• Monitoring active

• CI/CD active

• Production deployment successful