Base44 deployment

Base44 App Not Loading After Publishing

Your Base44 app works perfectly in the editor and preview mode, but after publishing it to a live URL, the app doesn't load. Users see a blank page, a loading spinner that never resolves, or an error message.

This is a common and stressful issue because the app appeared to be fully functional during development. The disconnect between the editor environment and the published environment can be caused by several factors related to how Base44 builds and deploys apps.

In some cases, the app partially loads (the layout appears but data doesn't populate), or certain pages work while others don't.

Error Messages You Might See

Application failed to load ChunkLoadError: Loading chunk failed Uncaught TypeError: Cannot read properties of null
Application failed to loadChunkLoadError: Loading chunk failedUncaught TypeError: Cannot read properties of null

Common Causes

  1. The publish process completed with warnings that were overlooked, resulting in a partially built app
  2. Environment-specific settings (API keys, database connections) differ between preview and production
  3. JavaScript errors in custom code or components that only manifest in the production build
  4. The app references assets or resources that are available in the editor but not included in the published build
  5. A recent change introduced an error that breaks the production build but not the editor preview

How to Fix It

Check the publish logs in your Base44 dashboard for any warnings or errors that occurred during the build process. Even warnings can indicate issues that cause the published app to malfunction.

Open the published app in a browser with the developer console open (F12). JavaScript errors in the console often point directly to the failing component or configuration.

Try re-publishing the app after reverting your most recent changes. If the previous version worked, compare what changed. For persistent deployment failures, a developer can examine the build output and production environment configuration.

Real developers can help you.

MFox MFox Full-stack professional senior engineer (15+years). Extensive experience in software development, qa, and IP networking. Tejas Chokhawala 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. Sage Fulcher 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) Jen Jacobsen 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 β€” 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. Jacek Rozanski 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. Omar Faruk 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. Milan Surelia 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: πŸ’‘ Developing cross-platform apps using Flutter, Dart, and Jetpack Compose for Android, iOS, and Web. πŸ–‹οΈ 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. πŸš€ Launched Compose101 β€” a Jetpack Compose starter kit to speed up Android development. 🌟 Open source contributions on Github & StackOverflow for Flutter & Dart πŸŽ–οΈ 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. Krishna Sai Kuncha Krishna Sai Kuncha Experienced Professional Full stack Developer with 8+ years of experience across react, python, js, ts, golang and react-native. Developed inhouse websearch tooling for AI before websearch was solved : ) Matthew Jordan 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. David Olverson 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.

You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.

Get Help

Frequently Asked Questions

Why does my Base44 app work in preview but not when published?

The published version uses a different build process and environment. Check the publish logs for errors and open the browser developer console on the published URL for JavaScript errors.

How do I fix a Base44 app that shows a blank page after publishing?

Open the browser developer console to see error messages. Common causes include missing environment settings or JavaScript errors in custom code that only appear in production builds.

Can I roll back a Base44 deployment?

Check if Base44 offers version history or a way to re-publish a previous version. If not, revert your recent changes in the editor and re-publish.

Related Base44 Issues

Can't fix it yourself?
Real developers can help.

You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.

Get Help