Common Issues
general
My App Works on My Computer but Not When I Share the Link
Everything looks perfect when you test your app on your own computer. But when you send the link to a friend, customer, or investor, they see errors, a blank page, or something completely broken. It's embarrassing and confusing.
This happens because your computer has a special setup that makes the app work — things like saved passwords, local files, or settings that only exist on your machine. When someone else opens the link, none of that is available, so the app falls apart.
It might also be that your app is still running only on your computer (localhost) and isn't actually published to the internet yet, even though you have a link that looks like it should work.
Error Messages You Might See
This site can't be reached
404 Not Found
Application error - check logs
Blank white page
Failed to load resource
Common Causes
- App isn't actually deployed — You're running it on your computer (localhost) and sharing a link that only works on your machine
- Missing environment variables — Secret keys and passwords are saved on your computer but weren't added to the hosting platform
- Database not connected in production — Your app talks to a local database on your computer, not one on the internet
- Mixed HTTP and HTTPS — Your live site uses HTTPS but some resources are loaded over HTTP, which browsers block
- Browser cache showing old version — You see the working version from your cache, but others get the broken deployed version
How to Fix It
- Test in a private/incognito window — Open your link in an incognito browser tab to see what others actually see
- Check your hosting platform — Make sure your app is actually deployed and the hosting shows it as "live" or "active"
- Add your secret keys to the hosting — Any passwords or API keys on your computer need to be added to your hosting platform's environment variables section
- Check the deployment logs — Look at your hosting platform for error messages during the build or deploy process
- Test on your phone — Open the link on your phone (not connected to your home WiFi) to confirm it works outside your network
Real developers can help you.
Pratik
SWE with 15+ years of experience building and maintaining web apps and extensive BE infrastructure
Nam Tran
10 years as fullstack developer
Jen Jacobsen
I’m a Full-Stack Developer with over 10 years of experience building modern web and mobile applications. I enjoy working across the full product lifecycle — turning ideas into real, well-built products that are intuitive for users and scalable for businesses.
I particularly enjoy building mobile apps, modern web platforms, and solving complex technical problems in a way that keeps systems clean, reliable, and easy to maintain.
Mehdi Ben Haddou
- Founder of Chessigma (1M+ users) & many small projects
- ex Founding Engineer @Uplane (YC F25)
- ex Software Engineer @Amazon and @Booking.com
Matt Butler
Software Engineer @ AWS
Caio Rodrigues
I'm a full-stack developer focused on building practical and scalable web applications. My main experience is with **React, TypeScript, and modern frontend architectures**, where I prioritize clean code, component reusability, and maintainable project structures.
I have strong experience working with **dynamic forms, state management (Redux / React Hook Form), and complex data-driven interfaces**. I enjoy solving real-world problems by turning ideas into reliable software that companies can actually use in their daily operations.
Beyond coding, I care about **software quality and architecture**, following best practices for componentization, code organization, and performance optimization.
I'm also comfortable working across the stack when needed, integrating APIs, handling business logic, and helping transform prototypes into production-ready systems.
My goal is always to deliver solutions that are **simple, efficient, and genuinely useful for the people using them.**
Jacek Rozanski
Senior PHP/Symfony developer and DevOps engineer with 20+ years of professional experience, running opcode.pl (web development agency, est. 2004).
Day job: I'm the sole backend developer at merketing company where I own and maintain 11 PHP/Symfony microservices on AWS (ECS Fargate, RDS, S3, CloudFront), handle the full CI/CD pipeline (Bitbucket Pipelines, Docker), and manage monitoring with Sentry and CloudWatch. These services handle high request volumes in production every month.
What I bring to AI-built apps:
- I audit and fix security issues (OWASP methodology), performance bottlenecks, and architectural problems in codebases generated by Cursor, Claude Code, Lovable, Bolt, and v0
- I refactor AI-generated prototypes into production-grade applications with proper error handling, testing, and clean architecture (SOLID, DDD, hexagonal architecture)
- I set up the infrastructure AI tools don't touch: AWS hosting, CI/CD pipelines, automated deployments, database optimization, monitoring, and alerting
- I integrate external services: payment providers, email systems, partner APIs, SSO/auth
Tech stack: PHP 8.x, Symfony, React, Next.js, PostgreSQL, MySQL, Docker, AWS (ECS, RDS, S3, SQS/SNS, CloudFront), Terraform, Supabase. I also use AI tools daily (Claude Code, Cursor) in my own workflow, so I understand both the strengths and the gaps in AI-generated code.
Based in Poland (CET timezone). Available for async work and calls during EU/US business hours.
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.
Jared Hasson
Full time lead founding dev at a cyber security saas startup, with 10 yoe and a bachelor's in CS. Building & debugging software products is what I've spent my time on for forever
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.
Describe what's wrong in plain English. No technical knowledge needed.
Get HelpFrequently Asked Questions
What does 'localhost' mean?
Localhost means the app is running only on your own computer. It's like a private preview. To let others see it, you need to deploy (publish) it to a hosting service like Vercel, Netlify, or Heroku.
Why does it work in my browser but not my friend's?
Your browser might be showing a cached (saved) version, or your computer has settings and passwords that the live version doesn't have. Always test in an incognito window to see the real version.