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.
Sage Fulcher
Hey I'm Sage! Im a Boston area software engineer who grew up in South Florida. Ive worked at a ton of cool places like a telehealth kidney care startup that took part in a billion dollar merger (Cricket health/Interwell health), a boutique design agency where I got to work on a ton of exciting startups including a photography education app, a collegiate Esports league and more (Philosophie), a data analytics as a service startup in Cambridge (MA) as well as at Phillips and MIT Lincoln Lab where I designed and developed novel network security visualizations and analytics. I've been writing code and furiously devoted to using computers to make people’s lives easier for about 17 years. My degree is in making computers make pretty lights and sounds. Outside of work I love hip hop, the Celtics, professional wrestling, magic the gathering, photography, drumming, and guitars (both making and playing them)
Rudra Bhikadiya
I build and fix web apps across Next.js, Node.js, and DBs.
Comfortable jumping into messy code, broken APIs, and mysterious bugs.
If your project works in theory but not in reality, I help close that gap.
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.
Stanislav Prigodich
15+ years building iOS and web apps at startups and enterprise companies. I want to use that experience to help builders ship real products - when something breaks, I'm here to fix it.
Jaime Orts-Caroff
I'm a Senior Android developer, currently working at Aircall. I'm open to work in various fields!
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.
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.**
Omar Faruk
As a Product Engineer at Klasio, I contributed to end-to-end product development, focusing on scalability, performance, and user experience.
My work spanned building and refining core features, developing dynamic website templates, integrating secure and reliable payment gateways, and optimizing the overall system architecture.
I played a key role in creating a scalable and maintainable platform to support educators and learners globally.
I'm enthusiastic about embracing new challenges and making meaningful contributions.
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.
rayush33
JavaScript (React.js, React Native, Node.js) Developer with demonstrated industry experience of 4+ years, actively looking for opportunities to hone my skills as well as help small-scale business owners with solutions to technical problems
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.