Hire the Best Web Application Developers in California

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Rating is 4.9 out of 5.
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Based on 227 client reviews
Andres M.

San Diego, California

$150/hr
5.0
24 jobs

Hi, my name is Andres. I am a full stack developer with over 15 years of experience building web applications from the ground up. I specialize in data driven AngularJS and Angular applications with NodeJS backends. If you are passionate about your vision, let's talk, I will be happy to help make it a reality.

  • Web Application
  • CSS
  • MySQL
  • Angular
  • AngularJS
  • Bootstrap
  • JavaScript
  • API Integration
  • Twilio API
  • SCSS
  • Stripe
  • Database Architecture
  • Database Design
  • Azure App Service
  • SendGrid
Mihai E.

Los Angeles, California

$120/hr
4.4
45 jobs

I am a seasoned lead software engineer and consultant with 10 years of experience in the information technology sector. Professional focal points include consultancy duties, full-stack engineering, application development, agile methodology, code writing, coaching and development programs, and numerous facets of technical issue resolution.

  • CSS
  • PHP
  • JavaScript
  • Java
  • .NET Framework
  • SQL
  • Symfony
  • Agile Software Development
  • API
  • Automated Testing
  • UX & UI
  • Unit Testing
Donald N.

Los Angeles, California

$20/hr
5.0
1 jobs

Hi there! ๐Ÿ‘‹ Iโ€™m a Full Stack Systems and App Developer with over 7 years of experience crafting high-performance applications, scalable backend systems, and intuitive user interfaces for startups, enterprises, and everything in between. Whether you're building a lightning-fast single-page application, a robust backend API, or a cross-platform mobile app, I bring together deep technical expertise, architectural thinking, and a relentless commitment to clean, maintainable code. ๐Ÿ’ก What I Do As a full stack developer, I thrive at the intersection of backend architecture, frontend design, and system-level logic. I build entire systems from the ground upโ€”or jump into existing codebases and elevate them to the next level. โœ… Web Apps (Admin panels, dashboards, marketplaces, SaaS platforms) โœ… Mobile Apps (React Native, Flutter, or native Android/iOS) โœ… System Integrations (APIs, microservices, third-party tools) โœ… Custom APIs (REST & GraphQL) โœ… Authentication Systems (JWT, OAuth2, SSO, multi-factor auth) โœ… Real-time Features (WebSockets, Push Notifications, Live Updates) โœ… DevOps (CI/CD pipelines, Docker, NGINX, cloud deployments) โœ… Security & Performance Optimization โš™๏ธ Tech Stack I Master Frontend #React, Next.js, Vue.js #TailwindCSS, Bootstrap, Material UI #Redux, Zustand, SWR, React Query #TypeScript, JavaScript (ES6+) Backend #Node.js, Express, NestJS #Python (FastAPI, Flask), PHP (Laravel) #Java (Spring Boot), Go (Gin/Fiber) #RESTful API & GraphQL #WebSockets, Redis, RabbitMQ Databases #MongoDB, PostgreSQL, MySQL #Firebase, Supabase #Redis for caching #ElasticSearch for search optimization Mobile #React Native, Flutter #Expo, Firebase Auth & Realtime DB #Native modules & integrations #Offline storage & synchronization DevOps / Tools #Docker, NGINX, PM2 #GitHub Actions, GitLab CI/CD, Jenkins #AWS (EC2, S3, Lambda), Vercel, Netlify #Postman, Swagger, Insomnia #Unit, integration & E2E testing (Jest, Cypress, Mocha) ๐Ÿš€ Why Work With Me? ๐Ÿ”น Systematic Problem Solver โ€“ I break down complex problems and solve them with modular, scalable solutions. ๐Ÿ”น Pixel-Perfect Delivery โ€“ I translate Figma/AdobeXD/Sketch designs into highly responsive, fluid UIs. ๐Ÿ”น Scalable Thinking โ€“ Every system I build is designed with future growth, performance, and maintainability in mind. ๐Ÿ”น Transparent Communication โ€“ I value clear communication, regular updates, and real-time collaboration. ๐Ÿ”น Fast & Reliable โ€“ Tight deadline? No problem. I deliver production-ready solutions with zero compromise on quality. ๐Ÿ”ง What Iโ€™ve Built Before ๐Ÿ“ˆ A B2B SaaS platform for sales analytics used by Fortune 500 teams ๐Ÿ’Š A full-featured EHR (Electronic Health Records) system for clinics ๐Ÿ›’ E-commerce mobile apps with real-time inventory syncing ๐Ÿ” Secure document management platform with role-based access ๐Ÿ“ฑ Social networking app with live chat, feeds, and stories ๐Ÿ’ผ Admin dashboards for multi-tenant enterprise CRMs โญ Client Testimonials โ€œOne of the best developers Iโ€™ve worked with. Built our entire app from zero to MVP in under 3 weeks. Clean code and proactive communication.โ€ โ€” Startup Founder, HealthTech (USA) โ€œTakes full ownership of systems and brings solutions, not problems. If you need a long-term dev, hire this guy now.โ€ โ€” CTO, SaaS Product (Germany) ๐Ÿ“ฉ Letโ€™s Build Together Whether you're looking to build from scratch, need an extra brain on your dev team, or want to scale your app to the next levelโ€”Iโ€™m ready to help. ๐Ÿ“† Send me a message and letโ€™s talk about your project! I respond quickly and am happy to hop on a call or review your idea.

  • Web Application
  • App Development
  • CSS
  • Android App Development
  • Web Development
  • Django
  • Python
  • Kotlin
  • HTML5
  • Firebase
  • GitHub
  • Front-End Development Framework
  • Back-End Development Framework
  • Bootstrap
  • UI/UX Prototyping
Eddie C.

Sacramento, California

$50/hr
5.0
6 jobs

Hi! My name is Eddie. I am a front-end web developer based in Sacramento, California. I work full time as a software developer building a SaaS insurance platform. I focus on delivering results with intuitive design and functional simplicity.

  • Responsive Design
  • Website
  • PHP
  • JavaScript
  • WordPress
  • HTML5
  • CSS 3
  • jQuery
  • Web Design
  • React
Ittrat F.

Sacramento, California

$35/hr
5.0
6 jobs

๐—ฆ๐—ฒ๐—ป๐—ถ๐—ผ๐—ฟ ๐—™๐˜‚๐—น๐—น-๐—ฆ๐˜๐—ฎ๐—ฐ๐—ธ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—ฒ๐—ฟ | ๐—ก๐—ผ๐—ฑ๐—ฒ.๐—ท๐˜€ | ๐—ก๐—ฒ๐˜…๐˜.๐—ท๐˜€ | ๐—ฅ๐—ฒ๐—ฎ๐—ฐ๐˜.๐—ท๐˜€ | ๐—ฃ๐—ผ๐˜€๐˜๐—ด๐—ฟ๐—ฒ๐—ฆ๐—ค๐—Ÿ | ๐—”๐—ช๐—ฆ | ๐—”๐—ฃ๐—œ ๐—œ๐—ป๐˜๐—ฒ๐—ด๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป | ๐— ๐—˜๐—ฅ๐—ก ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—ฒ๐—ฟ I am a Senior Full Stack Developer with 10+ years of experience building modern, scalable and high-performance web applications from frontend to backend. I specialize in React.js, Next.js, Node.js, and PostgreSQL, delivering complete end-to-end solutions with clean architecture, responsive design, and seamless API integrations. My focus is on building full stack products that work beautifully on the frontend and scale reliably on the backend. I have worked on healthcare, fintech, logistics and SaaS platforms, handling everything from pixel-perfect UI to database design, REST API development, and cloud deployment. ๐—ฃ๐—ฟ๐—ผ๐—ณ๐—ฒ๐˜€๐˜€๐—ถ๐—ผ๐—ป๐—ฎ๐—น ๐—˜๐˜…๐—ฝ๐—ฒ๐—ฟ๐—ถ๐—ฒ๐—ป๐—ฐ๐—ฒ ๐Ÿญ- ๐—ฆ๐—ฒ๐—ป๐—ถ๐—ผ๐—ฟ ๐—™๐˜‚๐—น๐—น-๐—ฆ๐˜๐—ฎ๐—ฐ๐—ธ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—ฒ๐—ฟ | ๐—™๐—ถ๐—ป๐˜๐—ฒ๐—ฐ๐—ต ๐—ฃ๐—น๐—ฎ๐˜๐—ณ๐—ผ๐—ฟ๐—บ - Built fintech platform with virtual cards, wallet flows, and real-time dashboards - Developed REST APIs, database architecture, and responsive frontend UI - Managed complex app states including loading, errors, modals, and empty states Skills: React.js, Next.js, Node.js, PostgreSQL, REST API, TypeScript, Material UI ๐Ÿฎ- ๐—ฆ๐—ฒ๐—ป๐—ถ๐—ผ๐—ฟ ๐—™๐˜‚๐—น๐—น-๐—ฆ๐˜๐—ฎ๐—ฐ๐—ธ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—ฒ๐—ฟ | ๐—Ÿ๐—ผ๐—ด๐—ถ๐˜€๐˜๐—ถ๐—ฐ๐˜€ ๐—ฃ๐—น๐—ฎ๐˜๐—ณ๐—ผ๐—ฟ๐—บ - Built logistics platform with shipment tracking, booking flows, and operational dashboards - Designed scalable REST APIs and backend business logic - Delivered responsive, maintainable full-stack architecture Skills: React.js, Next.js, Node.js, Express.js, PostgreSQL, AWS, TypeScript ๐Ÿฏ- ๐—™๐˜‚๐—น๐—น-๐—ฆ๐˜๐—ฎ๐—ฐ๐—ธ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—ฒ๐—ฟ | ๐—›๐—ฒ๐—ฎ๐—น๐˜๐—ต๐—ฐ๐—ฎ๐—ฟ๐—ฒ ๐—ฃ๐—น๐—ฎ๐˜๐—ณ๐—ผ๐—ฟ๐—บ - Developed healthcare web app with frontend + backend ownership - Built REST APIs, database management, and responsive UI architecture - Worked long-term with US client on ongoing feature development Skills: React.js, Node.js, PostgreSQL, REST API, TypeScript, AWS ๐—ž๐—ฒ๐˜† ๐—ฆ๐—ธ๐—ถ๐—น๐—น๐˜€ & ๐—ง๐—ฒ๐—ฐ๐—ต๐—ป๐—ผ๐—น๐—ผ๐—ด๐—ถ๐—ฒ๐˜€ ๐—™๐—ฟ๐—ผ๐—ป๐˜๐—ฒ๐—ป๐—ฑ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—บ๐—ฒ๐—ป๐˜ - React.js, Next.js, JavaScript (ES6+), TypeScript - Redux, State Management, Component-Based Architecture ๐—จ๐—œ & ๐—ฆ๐˜๐˜†๐—น๐—ถ๐—ป๐—ด - Tailwind CSS, Material UI, Responsive Web Design - Pixel-Perfect UI, Cross-Device Development ๐—•๐—ฎ๐—ฐ๐—ธ๐—ฒ๐—ป๐—ฑ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—บ๐—ฒ๐—ป๐˜ - Node.js, Express.js, Nest.js, Python, Flask - REST API, GraphQL, WebSockets, Microservices ๐——๐—ฎ๐˜๐—ฎ๐—ฏ๐—ฎ๐˜€๐—ฒ๐˜€ - PostgreSQL, MongoDB, MySQL, Redis - Database Design, Query Optimization, Data Modeling ๐—–๐—น๐—ผ๐˜‚๐—ฑ & ๐——๐—ฒ๐˜ƒ๐—ข๐—ฝ๐˜€ - AWS, Docker, CI/CD - Vercel, Heroku, Azure, Firebase ๐—ง๐—ผ๐—ผ๐—น๐˜€ & ๐—–๐—ผ๐—น๐—น๐—ฎ๐—ฏ๐—ผ๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป - GitHub, Jira, Trello, Agile/Scrum - Figma, Cross-Functional Team Collaboration ๐—™๐—น๐—ฒ๐˜…๐—ถ๐—ฏ๐—น๐—ฒ ๐—–๐—ผ๐—น๐—น๐—ฎ๐—ฏ๐—ผ๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป I work across multiple time zones and adapt to full-time, part-time, or milestone-based projects, ensuring clear communication and on-time delivery. ๐—ช๐—ต๐˜† ๐—ช๐—ผ๐—ฟ๐—ธ ๐—ช๐—ถ๐˜๐—ต ๐— ๐—ฒ? โœ… 10+ years of Full-Stack experience across frontend and backend โœ… End-to-end ownership, from UI design to database and cloud deployment โœ… Clean, scalable, and maintainable code across the entire stack โœ… Experience across fintech, healthcare, logistics and SaaS โœ… Reliable, client-focused developer committed to on-time delivery ๐—ž๐—ฒ๐˜†๐˜„๐—ผ๐—ฟ๐—ฑ๐˜€ Full Stack Developer, MERN Developer, React Developer, Next.js Developer, Node.js Developer, JavaScript Developer, TypeScript Developer, REST API Developer, PostgreSQL Developer, AWS Developer, Python Developer, Backend Developer, Frontend Developer, Web Application Developer, SaaS Developer, Fintech Developer, Healthcare Platform Developer, Logistics Platform Developer, Responsive Web Design, API Integration, Cloud Deployment

  • Responsive Design
  • Web Development
  • JavaScript
  • React
  • Next.js
  • TypeScript
  • Front-End Development
  • Tailwind CSS
  • SaaS Development
  • Front-End Development Framework
  • Application Optimization
  • GitHub
  • Vercel
  • API Integration
  • User Interface Design
  • Modern Style
  • Material UI
  • Redux
  • REST API
  • Git
Numan U.

Sacramento, California

$40/hr
4.8
69 jobs

๐—ง๐—ผ๐—ฝ ๐—ฅ๐—ฎ๐˜๐—ฒ๐—ฑ ๐—ฃ๐—น๐˜‚๐˜€ | ๐Ÿญ๐Ÿฌ๐Ÿฌ% ๐—๐—ผ๐—ฏ ๐—ฆ๐˜‚๐—ฐ๐—ฐ๐—ฒ๐˜€๐˜€ | ๐Ÿญ๐Ÿฏ+ ๐—ฌ๐—ฒ๐—ฎ๐—ฟ๐˜€ | ๐Ÿด,๐Ÿฌ๐Ÿฌ๐Ÿฌ+ ๐—จ๐—ฝ๐˜„๐—ผ๐—ฟ๐—ธ ๐—›๐—ผ๐˜‚๐—ฟ๐˜€ | $๐Ÿฎ๐Ÿฌ๐Ÿฌ๐—ž+ ๐—˜๐—ฎ๐—ฟ๐—ป๐—ฒ๐—ฑ | I'm a senior .NET / C# developer and Azure cloud architect who builds and scales production systems for companies that can't afford downtime or rework โ€” healthcare platforms, fintech products, e-commerce systems, and real estate/property-management software. If your project needs more than someone who writes code to spec โ€” if you need someone who can architect the solution, own the delivery, and still be there for support six months later โ€” that's the role I take on. WHAT I BUILD โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€ โœฆ SaaS Platforms โ€” multi-tenant, subscription-based .NET Core / Azure applications built to scale from a handful of users to enterprise volume โœฆ Healthcare Systems โ€” HIPAA-aware EHR/EMR platforms, HL7/FHIR integrations, and clinical workflow tools built to compliance standards โœฆ Fintech & Payments โ€” secure transaction processing, Stripe/PayPal integrations, reporting and reconciliation systems, PCI-conscious architecture โœฆ E-Commerce Platforms โ€” custom storefronts, order/inventory management, and integrations with payment gateways, CRMs, and ERPs โœฆ Real Estate & Property Management Systems โ€” listing platforms, tenant/lease management tools, and workflow automation for property teams โœฆ AI-Powered Features โ€” OpenAI/LLM integrations, intelligent document processing, and AI-assisted workflows added to existing .NET applications โœฆ Legacy Modernization โ€” turning outdated ASP.NET/VB.NET systems into maintainable, cloud-ready .NET 8 platforms without breaking what already works TECH STACK โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€ + Backend: C# ยท .NET 8 / .NET Core ยท ASP.NET Core ยท ASP.NET MVC ยท Web API ยท Entity Framework Core ยท LINQ ยท Blazor ยท SignalR ยท Microservices ยท REST & SOAP APIs + Frontend: Angular ยท React ยท TypeScript ยท JavaScript ยท HTML5 ยท CSS3 ยท Blazor UI + Cloud & DevOps: Microsoft Azure (App Services, Functions, AKS, Service Bus, Key Vault, Azure SQL) ยท AWS (EC2, Lambda, RDS, S3) ยท Azure DevOps ยท GitHub Actions ยท CI/CD ยท Docker ยท Kubernetes ยท Infrastructure as Code + Databases: SQL Server ยท PostgreSQL ยท Cosmos DB ยท MongoDB ยท Stored Procedures & Query Optimization for high-volume systems + Integrations: Stripe ยท PayPal ยท Twilio ยท SendGrid ยท OAuth 2.0 ยท HL7 ยท FHIR ยท CRM/ERP integrations HOW I WORK โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€ I stay involved from architecture through deployment โ€” writing clean, documented, production-ready code, and communicating progress clearly at every step. I manage scope, timelines, and stakeholder expectations as carefully as I manage the codebase itself. Depending on what your project needs, I can work as a hands-on senior engineer, a solution architect, or a long-term technical lead. I'll tell you honestly, early, if I'm the right fit for what you're building. Send me your project scope and I'll respond within a few hours.

  • C#
  • Microsoft Azure
  • Azure DevOps Server
  • ASP.NET
  • ASP.NET MVC
  • ASP.NET Core
  • .NET Framework
  • AWS Development
  • Azure DevOps
  • DevOps
  • ADO.NET
  • Microsoft SQL Server
  • Web Form
  • ASP.NET Web API
  • .NET Core
  • VB.NET
  • .NET Stack
  • Azure App Service
  • Angular
  • DevOps Engineering

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