Hire the Best CSS3 Developers
in Costa Rica

More than 3,000 reviews on G2
Rating is 4.5 out of 5.
4.5/5
of Upwork by G2 peer reviewers
Braulio B.

Santa Ana, Costa Rica

$30/hr
5.0
12 jobs

Seasoned full stack developer with over 8 years of hands-on experience specializing in .NET, React.js, Node.js, TypeScript, .NET Core, and GraphQL. Proven track record of successfully delivering robust and scalable web applications from concept to deployment. Adept at leveraging a diverse skill set to drive innovation and solve complex technical challenges. Strong team player with excellent communication skills, able to collaborate effectively across departments to achieve project goals. Committed to staying at the forefront of emerging technologies to deliver cutting-edge solutions.

  • CSS 3
  • JavaScript
  • HTML5
  • Node.js
  • GraphQL
  • React
  • .NET Framework
  • C#
  • HTML
  • API
  • React Native
  • Manual Testing
  • .NET Core
  • ASP.NET
  • ASP.NET MVC
Susan S.

San Pedro, Costa Rica

$20/hr
4.6
3 jobs

I’m a Front-End Web Developer with hands-on experience building websites and user interfaces from scratch, from initial layout to final implementation. I regularly work from Figma mockups to translate designs into clean, responsive front-end code, and I’ve integrated front-end applications with API endpoints to fetch, manage, and display dynamic data in React applications. I focus on creating clean, responsive, and user-friendly interfaces using modern front-end tools. I’m comfortable working independently or joining existing codebases, adapting quickly, and delivering well-structured, maintainable UI. What I can help you with: - Building front-end interfaces from scratch using React - Implementing designs from Figma mockups into pixel-accurate, responsive UI - Creating simple Figma mockups when a project needs a starting layout - Responsive, mobile-first layouts with HTML5, CSS3, and Tailwind CSS - Clean, reusable, and maintainable UI components - Integrating front-end applications with REST APIs and endpoints to fetch and display dynamic data - UI improvements, bug fixes, and layout refinements - Fast-loading static websites with clean HTML and CSS Technical background: - Strong foundation in JavaScript and modern React development - Experience with state management (Context API, Redux) - Familiar with front-end testing, debugging, and best practices - Version control using Git and collaborative workflows - Background in SQL databases and technical support environments Currently, I’m expanding my skills in the modern React ecosystem, including Next.js, while continuously strengthening my front-end expertise. Why clients like working with me: - Clear and proactive communication - Reliable, detail-oriented, and deadline-focused - Open to feedback and quick to apply improvements - Strong problem-solving mindset backed by IT and customer service experience I’m currently focused on Front-End projects such as React development, UI improvements, landing pages, and fast, responsive websites. If you’re looking for a dependable front-end developer who builds clean UI and communicates clearly, I’d be happy to work with you.

  • CSS
  • Front-End Development
  • JavaScript
  • HTML
  • React
  • EJS
  • Bootstrap
  • Tailwind CSS
  • Next.js
  • API
  • Figma
  • Redux
  • JSON
  • Jest
  • Material UI
Treisy J.

Alajuela, Costa Rica

$20/hr
5.0
9 jobs

🚀 Accelerate your software delivery by 60% with proven Agile leadership from Fortune 500 companies and high-growth startups, backed by deep technical expertise. I'm a Certified Scrum Master (CSM) and CAPM who transitioned from over 10 years as a Senior Web Engineer to Agile leadership, bringing unique technical credibility that accelerates team performance and removes blockers faster. **WHAT I DO:** ✅ Agile Transformation & Change Management ✅ Sprint Planning, Daily Standups & Retrospectives ✅ Backlog Refinement & Release Management ✅ Cross-Functional Team Leadership (4-16 developers) ✅ JIRA/Confluence Setup & Workflow Optimization ✅ Product Owner Coaching & Stakeholder Management ✅ Scrum@Scale Implementation for Multiple Teams **PROVEN RESULTS:** - Reduced delivery time by 60% through process redesign - Cut PI Planning meetings from 8 to 3 hours (60% time savings) - Increased team velocity by 40% using Scrum@Scale - Decreased defects by 25% via continuous improvement initiatives - Shortened release cycles from 2 months to 30 minutes - Improved product delivery by 20% through effective backlog management - Enhanced team engagement by 50% creating psychologically safe environments **INDUSTRIES SERVED:** Technology • SaaS • Enterprise Software • FinTech • Marketing Agency **WHY MY TECHNICAL BACKGROUND MATTERS:** Unlike typical Scrum Masters, my 10+ years as a developer mean I: → Understand technical debt and architecture decisions → Can evaluate story complexity and estimate accurately → Remove technical blockers without endless escalations → Speak the engineering team's language, earning immediate trust → Bridge business requirements with technical feasibility **CERTIFICATIONS:** - Certified Scrum Master (CSM) - Scrum Inc. - Scrum@Scale Practitioner - Scrum Inc. - CAPM - Certified Associate in Project Management (PMI) - Agile Metrics for Success - Project Management Institute - MBA in Business Administration (in progress) **CAREER PROGRESSION:** → Scrum Master at Fortune 500 tech corporation (2022-2025) → Scrum Master & Development Lead at SaaS startup (2021-2022) → Scrum Master & Senior UI Engineer at SaaS startup(2019-2022) → 10+ years in technical roles: Developer, Architect, Technical Lead **TECHNICAL EXPERTISE:** Frontend: React, NextJS, TypeScript, JavaScript, HTML5, CSS3 Backend: Python, Django, Node.js, SAP/ABAP, PHP Tools: JIRA, Confluence, Git, 🌎 **100% BILINGUAL:** English (Professional) | Spanish (Native) **AVAILABLE FOR:** - Ongoing Scrum Master services - Agile transformation consulting - Sprint facilitation & team coaching (hourly or per-sprint) - JIRA/Confluence setup & process optimization Let's discuss how I can help your team achieve consistent Sprint goals and deliver business value faster. Send me a message to schedule a consultation call.

  • Scrum
  • Agile Project Management
  • Sprint Planning
  • Jira
  • Project Management
  • Atlassian Confluence
  • Kanban Methodology
  • Scaled Agile Framework
  • Agile Software Development
  • Strategic Planning
  • Cross Functional Team Leadership
  • Process Improvement
Edgar C.

Santa Ana, Costa Rica

$30/hr
5.0
3 jobs

I ship production AI systems end-to-end with Claude Code as my primary tool. Three production SaaS shipped solo this year. Pregnalyze ranks #4 worldwide on Google for "miscarriage calculator" with thousands of monthly organic users (zero paid ads). Atiendo24 is a multi-tenant WhatsApp AI agent platform with Claude tool use, distributed Redis locks, double-layer Stripe idempotency, and an open-source MCP server published on npm. AdCopyStyles generates Meta ad copy from product URLs in under 30 seconds via an async BullMQ pipeline with a dedicated Railway worker. All live. All production-ready. Before going solo, I spent 4+ years at Publicis Global Delivery shipping production code for Fortune 500 clients: Amazon/Audible, Citi, Verizon. 13+ years total in software, the last year fully focused on AI-native SaaS. What I build: - AI-powered SaaS MVPs (Anthropic Claude API, OpenAI, multi-step agents with tool use) - MCP servers — making your product controllable from Claude Desktop and any MCP client (published one on npm: @edgarconejo/atiendo24-mcp-server) - Async AI pipelines with BullMQ + Railway workers for LLM workloads that can't run in a serverless timeout - Multi-tenant Next.js + Supabase architectures with strict RLS isolation - WhatsApp AI agents using Cloud API direct (no Twilio markup) - Stripe integrations (subscriptions, webhooks, customer portal, freemium flows) - Conversion-focused SaaS landing pages Why clients choose me: I think about whether what you're building will actually work in the market — because I've been on the other side. I've run Meta Ads for my own products, launched on Product Hunt. I don't just ship features, I own the quality of what I build. Every phase ends with a security audit, QA checks, and a full diff review before accepting any changes. Data leaks, auth vulnerabilities, and edge cases get caught before they reach production, not after. You get code that works correctly, not just code that works. Claude Code is my daily interface, it's how I move fast without cutting corners on quality. Single senior engineer with the throughput historically associated with a team. Tech stack: Next.js · TypeScript · Tailwind CSS · Supabase · Prisma · PostgreSQL · BullMQ · Redis/Upstash · Stripe · Anthropic Claude API · Claude Code · MCP · WhatsApp Cloud API · Twilio · OpenAI · Resend · Sentry · GA4 · Vercel · Railway Available for MVP builds, founding engineer roles, AI infrastructure work, and Anthropic-stack consulting. Native Spanish, fluent English, EST/PST overlap from Costa Rica. Let's talk about what you're shipping.

  • Next.js
  • TypeScript
  • React
  • Node.js
  • Supabase
  • Stripe API
  • Tailwind CSS
  • OpenAI API
  • Chatbot Development
  • SaaS Development
  • Artificial Intelligence
  • Claude
  • Prompt Engineering
  • API Integration
  • PostgreSQL
  • AI Agent Development
  • Twilio API
  • Vercel
  • REST API
  • OAuth
Maria C.

Purral, Costa Rica

$20/hr
5.0
9 jobs

Do you need a bilingual (EN/ES) virtual assistant who is organized, fast, and reliable? I can help you manage your daily tasks and keep your business running smoothly. I specialize in: ✅ Data entry in Excel and Google Sheets ✅ Email and schedule management ✅ Admin support and client follow-ups ✅ Report creation and file organization Tools I use daily: Excel, Google Sheets, Notion, Trello, Gmail, ChatGPT I'm professional, proactive, and focused on quality and clarity in every task. Let's work together!

  • CSS 3
  • Java
  • JavaScript
  • API Development
  • Python
  • HTML5
  • MySQL
  • Postman
  • PostgreSQL
  • GitHub
  • Figma
  • SQL
  • Spring Boot
  • JetBrains IntelliJ IDEA
  • Oracle Cloud
Andres A.

San Jose, Costa Rica

$60/hr
4.6
15 jobs

I'm a 100% bilingual Full Stack and Automation Engineer with over 20 years of experience working with US-based companies. I've done mostly Web Development, REST APIs, QA lead, Test Automation and DevOps-related tasks, like deployment and provisioning automation. Regarding Web Development, I specialize in Wordpress, PHP and Java, and I have thorough experience integration with 3rd party APIs, like payment gateways and social media sites. I also focus on the client project as a whole thing, and not only as a development project, so I will suggest and encourage usage of web analytics, cloud based solutions and anything I can do to help your business succeed. Regarding QA and Test Automation, I have experience as QA Manager, handling teams of QA Engineers, and I have successfully implemented test automation frameworks for ECommerce and SaaS applications. These frameworks were based on Selenium WebDriver, using Java, TestNG and Maven. In addition to this, I have implemented internal Selenium Grids, using virtual machines and Docker containers, that supported up to 60 concurrent tests, executed by a Jenkins job. This enabled a suite of almost 300 regression tests to run in under 15 minutes, enabling the development team to run full regressions on the sites multiple times per day. I'm more than happy to offer you my services, so I'm always willing to be contacted for an interview. I'll be thrilled to be a part of your projects!

  • CSS 3
  • WordPress
  • Java
  • HTML5
  • PHP
  • JavaScript
  • Selenium
  • Selenium WebDriver
  • Project Management
  • Kubernetes
  • Amazon Web Services
  • Google Cloud Platform
  • Python
  • Terraform

How it works

Post a job for free Post a job

Tell us what you need. Create your own job post or generate one with AI then filter talent matches.

Hire top talent fast

Consult, interview, and hire quickly, so you can meet the freelancers you're excited about.

Collaborate easily

Use Upwork to chat or video call, share files, and track project progress right from the app.

Payment simplified

Manage payments in one place with flexible billing options. Only pay for approved work, hourly or by milestone.

Don't just take our word for it

How do I hire a CSS3 Developer in Costa Rica on Upwork?

You can hire a CSS3 Developer in Costa Rica on Upwork in four simple steps:

  • Create a job post tailored to your CSS3 Developer project scope. We'll walk you through the process step by step.
  • Browse top CSS3 Developer talent on Upwork and invite them to your project.
  • Once the proposals start flowing in, create a shortlist of top CSS3 Developer profiles and interview.
  • Hire the right CSS3 Developer for your project from Upwork, the world's largest work marketplace.

At Upwork, we believe talent staffing should be easy.

How much does it cost to hire a CSS3 Developer?

Rates charged by CSS3 Developers on Upwork can vary with a number of factors including experience, location, and market conditions. See hourly rates for in-demand skills on Upwork.

Why hire a CSS3 Developer in Costa Rica on Upwork?

As the world's work marketplace, we connect highly-skilled freelance CSS3 Developers and businesses and help them build trusted, long-term relationships so they can achieve more together. Let us help you build the dream CSS3 Developer team you need to succeed.

Can I hire a CSS3 Developer in Costa Rica within 24 hours on Upwork?

Depending on availability and the quality of your job post, it's entirely possible to sign up for Upwork and receive CSS3 Developer proposals within 24 hours of posting a job description.