Karl-Gustav Peterson

Led migration of a 100K+ page medical platform to a composable stack using TypeScript, Next.js 13, React 18, Node.js, Sanity, Algolia, Redis, Docker, Kafka, Vercel, AWS (S3, CloudFront, IAM, Route 53, Kubernetes), and Stripe. Architected structured content models in Sanity Studio v3 (GROQ, custom schemas, RBAC, i18n, webhooks) supporting multi-region deployments. Built scalable backend APIs with REST, JWT, RBAC, and Kafka for real-time event handling, integrating with AWS services for CPD tracking, PDF generation, and compliance logging. Implemented hybrid SSG, SSR, ISR with Next.js App Router, API Routes, and Edge Functions, deployed via Vercel and AWS, achieving green Core Web Vitals (LCP, INP, CLS). Integrated Algolia InstantSearch.js with unified indexing and webhook-triggered reindexing across 40K+ clinical articles and multimedia content. Optimized frontend performance with techniques like dynamic imports, React.memo, Tailwind CSS, and CloudFront caching. Developed secure subscri

• Delivered a cross-platform mobile and web MVP using TypeScript, React Native, Expo, React.js, Nest.js, Firebase, Sanity CMS, and Azure Cloud Services. • Built iOS and Android applications with structured state management and reusable UI components using React Native, Expo, Redux Toolkit, and Styled Components. • Developed responsive frontend with React.js, TypeScript, React Router, and Axios, deployed via Azure App Service and Azure Static Web Apps. • Engineered backend APIs and serverless business logic using Nest.js, Firebase Cloud Functions, and Azure Functions for scalable, modular, and maintainable microservices architecture. • Implemented real-time data sync and secure storage using Firebase Authentication, Firestore, Azure Blob Storage, and security rules. • Integrated dynamic content delivery with Sanity CMS, GROQ, YouTube API, optimized via Azure CDN. • Built push notification workflows using Expo Notifications, Firebase Cloud Messaging, Azure Notification Hubs, and Cloud Scheduler. • Implemented analytics via Firebase Analytics, Azure Application Insights, and custom event tracking. • Automated lifecycle workflows using Mailchimp API, HTTPS Functions, and Azure Logic Apps. • Configured CI/CD with Expo EAS Build, GitHub Actions, and Azure DevOps Pipelines

Architected cross-platform mobile applications using React Native, Expo CLI, and TypeScript; implemented passwordless authentication (Magic Link), JWT, OAuth, secure storage, GraphQL mutations with Apollo Client, and REST APIs with Axios. Developed QR voucher scanning with Expo Camera, deep linking, background tasks, and real-time validation. Optimized state and data management with GraphQL, Apollo Cache, and optimistic UI updates. Built reusable UI components with Storybook and followed atomic design. Improved performance via memoization and lazy loading; established CI/CD with GitHub Actions and Expo EAS Build, managing releases via App Store Connect and Google Play Console; enforced quality with ESLint, Prettier, Husky, Jest, and RN Testing Library.