Claude Code
testing
Critical Business Logic Has No Test Coverage
Your test suite covers utility functions and simple CRUD operations but completely misses the critical business logic: payment processing, access control checks, data transformations, and state machine transitions. The parts of your code that are most likely to cause catastrophic failures if broken have zero test coverage.
Claude Code tends to generate tests for the easiest-to-test code (pure functions, simple helpers) while skipping the complex, stateful, integration-heavy code that actually needs testing the most. The coverage report may show 70% overall but the missing 30% contains all the high-risk logic.
This becomes painfully apparent when a 'small refactor' of the payment flow introduces a bug that charges customers the wrong amount, and no test catches it before production.
Error Messages You Might See
Payment charged wrong amount in production
User accessed admin panel without admin role
Data export missing records for edge case
State transition allowed that should be blocked
Common Causes
- Complex setup avoided — Tests for payment flows require Stripe test mode, database seeding, and multi-step setup that AI skips
- External service dependencies — Code that calls external APIs is left untested because mocking the API is complex
- State machine transitions untested — Status changes (pending -> processing -> completed -> failed) and their edge cases have no coverage
- Error handling paths untested — Only the happy path is tested; what happens on timeout, invalid input, or partial failure is unknown
- Coverage metrics misleading — Line coverage is high because simple code is tested, but branch coverage on critical paths is zero
How to Fix It
- Identify critical paths first — List your top 10 most important features (payment, auth, data export). These get tests first regardless of overall coverage
- Write integration tests for critical flows — Test the full flow from request to database, using test databases and service test modes (Stripe test keys)
- Test every state transition — For each status field, test every valid transition AND verify invalid transitions are rejected
- Test error handling explicitly — Force errors (network timeouts, invalid data, permission denied) and verify the app handles them gracefully
- Use branch coverage, not line coverage — Configure your coverage tool to report branch coverage. Aim for 100% branch coverage on critical paths
Real developers can help you.
Franck Plazanet
I am a Strategic Engineering Leader with over 8 years of experience building high-availability enterprise systems and scaling high-performing technical teams. My focus is on bridging the gap between complex technology and business growth.
Core Expertise:
🚀 Leadership: Managing and coaching teams of 15+ engineers, fostering a culture of accountability and continuous improvement.
🏗️ Architecture: Enterprise Core Systems, Multi-system Integration (ERP/API/ETL), and Core Database Structure.
☁️ Cloud & Scale: AWS Expert; architected systems handling 10B+ monthly requests and managing 100k+ SKUs.
📈 Business Impact: Aligning tech strategy with P&L goals to drive $70k+ in monthly recurring revenue.
I thrive on "out-of-the-box" thinking to solve complex technical bottlenecks and am always looking for ways to use automation to improve business productivity.
Matthew Jordan
I've been working at a large software company named Kainos for 2 years, and mainly specialise in Platform Engineering. I regularly enjoy working on software products outside of work, and I'm a huge fan of game development using Unity. I personally enjoy Python & C# in my spare time, but I also specialise in multiple different platform-related technologies from my day job.
Tejas Chokhawala
Full-stack engineer with 5 years experience building production web apps using React, Next.js and TypeScript.
Focused on performance, clean architecture and shipping fast.
Experienced with Supabase/Postgres backends, Stripe billing, and building AI-assisted developer tools.
Prakash Prajapati
I’m a Senior Python Developer specializing in building secure, scalable, and highly available systems. I work primarily with Python, Django, FastAPI, Docker, PostgreSQL, and modern AI tooling such as PydanticAI, focusing on clean architecture, strong design principles, and reliable DevOps practices. I enjoy solving complex engineering problems and designing systems that are maintainable, resilient, and built to scale.
David Olverson
Solo dev shipping production apps with AI-assisted development. I specialize in rescuing broken Lovable/Bolt/Cursor builds and taking them to production. 10+ apps shipped including SaaS CRMs, gaming platforms, real estate tools, and Discord bots. Stack: Next.js 16, TypeScript, Tailwind CSS, FastAPI, PostgreSQL, Prisma. I use Claude Code with 50+ custom skills for rapid delivery. Average turnaround: 2-4 weeks from broken prototype to production.
Bastien Labelle
Full stack dev w/ 20+ years of experience
Vlad Temian
15+ years shipping production infrastructure for startups. Former CTO at qed.builders (acquired by The Sandbox).
Cursor ambassador and agentic tooling builder.
I've scaled systems, automated deployments, and built observability tools for AI coding workflows. I specialize in taking vibe-coded apps from broken prototype to production-ready: fixing Supabase auth/RLS, Stripe integrations, deployment pipelines, and cleaning up AI-generated spaghetti.
I build tools in this space (agentprobe, claudebin, micode) and understand both sides: how AI generates code and why it breaks.
https://blog.vtemian.com/
hanson1014
Full-stack developer experienced in fixing and deploying AI-generated apps from Lovable, Bolt.new, Cursor, and Replit. I specialize in debugging Supabase integration issues (auth flows, RLS policies, database connections), fixing broken deployments, resolving routing/blank screen problems, and cleaning up messy React/Vite codebases. I also build production apps with the Claude API and have shipped a Mac desktop dev tool (Nexterm from scratch. Based in Hong Kong, fast turnaround.
PawelPloszaj
I'm fronted developer with 10+ years of experience with big projects. I have small backend background too
Milan Surelia
Milan Surelia is a Mobile App Developer with 5+ years of experience crafting scalable, cross-platform apps at 7Span and Meticha. At 7Span, he engineers feature-rich Flutter apps with smooth performance and modern UI. As the Co-Founder of Meticha, he builds open-source tools and developer-focused products that solve real-world problems.
Expertise:
💡 Developing cross-platform apps using Flutter, Dart, and Jetpack Compose for Android, iOS, and Web.
🖋️ Sharing insights through technical writing, blogging, and open-source contributions.
🤝 Collaborating closely with designers, PMs, and developers to build seamless mobile experiences.
Notable Achievements:
🎯 Revamped the Vepaar app into Vepaar Store & CRM with a 2x performance boost and smoother UX.
🚀 Launched Compose101 — a Jetpack Compose starter kit to speed up Android development.
🌟 Open source contributions on Github & StackOverflow for Flutter & Dart
🎖️ Worked on improving app performance and user experience with smart solutions.
Milan is always happy to connect, work on new ideas, and explore the latest in technology.
You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.
Get HelpFrequently Asked Questions
What should I test first when coverage is low?
Prioritize by risk: payment processing, authentication and authorization, data mutations that can't be undone, and any code that handles money or personal data. These are the paths where bugs cause the most damage.
How do I test code that calls external APIs?
Use the service's test mode (Stripe test keys, SendGrid sandbox) for integration tests. Use recorded HTTP responses (nock, VCR, responses) for unit tests. Test both success and error responses from the API.