Replit
api
CORS Credentials and Cookies Not Sent
Authenticated API requests fail because cookies aren't sent. CORS blocks credentials even after preflight succeeds.
Credentials mode and CORS headers must align for cookies to transmit.
Error Messages You Might See
Credentials mode is 'include' but Access-Control-Allow-Credentials header is missing
Access-Control-Allow-Origin cannot use wildcard
Common Causes
- Client not sending credentials: 'include' in fetch
- Server not sending Access-Control-Allow-Credentials: true
- Access-Control-Allow-Origin set to * (incompatible with credentials)
- Cookie SameSite=Strict blocking cross-site cookies
How to Fix It
Client: fetch(url, { credentials: 'include' }). Server: response header Access-Control-Allow-Credentials: true. Set Access-Control-Allow-Origin to specific domain, NOT *. Ensure cookies have SameSite=None; Secure for cross-site. Configure Spring CORS with allowedOriginPatterns and allowCredentials=true.
Real developers can help you.
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:
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- 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.
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I’ve watched the tech landscape evolve over the last decade—from the structured days of Java Server Pages to the current "wild west" of Agentic-driven development. While AI can "vibe" a frontend into existence, I specialize in the architecture that keeps it from collapsing.
My expertise lies in the critical backend infrastructure: the parts that must be fast, secure, and scalable. I thrive on high-pressure environments, such as when I had only three weeks to architect and launch an Ethereum redemption system with minimal prior crypto knowledge, turning it into a major revenue stream.
What I bring to your project:
Forensic Debugging: I don't just "patch" bugs; I use tools like Datadog and Explain Analyzers to map out bottlenecks and resolve root causes—like significantly reducing memory usage by optimizing complex DB joins.
Full-Stack Context: Deep experience in Node.js and React, ensuring backends play perfectly with mobile and web teams.
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BurnHavoc
Been around fixing other peoples code for 20 years.
Mehdi Ben Haddou
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Meïr Ankri
Full-stack developer specializing in React / Next.js / Node.js with 6+ years of experience. I've worked across various sectors including automotive (Reezocar/Société Générale), healthcare (Medical Link SaaS), and e-commerce (Glasman). I build web apps end-to-end, from architecture to production, with a focus on scalability, performance, and code quality. I also mentor junior developers and contribute to technical decisions and code reviews.
You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.
Get HelpFrequently Asked Questions
How do I send cookies with fetch?
fetch(url, { credentials: 'include' }) - must also set server headers correctly
Can I use Access-Control-Allow-Origin: *?
Not with credentials. Use specific domain or null for local testing