Eduardo da Silva Kegler
Verified Expert in Engineering
Front-end Developer
Florianópolis - State of Santa Catarina, Brazil
Toptal member since December 7, 2021
Eduardo is a senior front-end engineer with 8 years of experience, the last 5 in fintech and crypto, specializing in auth flows and real-time UIs with React, TypeScript, and React Native. At Coinbase, he built sign-in flows for 200,000 daily users and led a signup redesign that lifted conversion by 35%. As the sole front-end engineer at Liquid Labs (GTE), Eduardo took a trading platform from zero to a testnet with over 1 million users in under a year. He now builds the NG.cash mobile app.
Portfolio
Experience
- JavaScript - 8 years
- Front-end - 8 years
- Design Systems - 7 years
- TypeScript - 7 years
- React - 7 years
- GraphQL - 6 years
- Next.js - 3 years
- OAuth - 3 years
Work Experience
Senior Software Engineer
NG.cash
- Delivered a new home navigation experience end to end in React Native, nearly solo, from RFC and design-system component to A/B experiment, feature flags, and observability, rolled out to 100% of adult users.
- Ported a full web e-commerce product to the mobile app, covering purchase flow, OTP login with auth guard, signup, and identity verification.
- Traced 3 of the top login errors to a single root cause in credential storage after password reset and shipped the fix.
- Cut AWS Lambda provisioned concurrency from 151 to 22 instances with a CDK rollout that kept a fallback in place.
- Removed about 40% of an onboarding web app's codebase and upgraded all its dependencies, closing open CVEs.
Senior Front-end Engineer
Liquid Labs
- Built GTE, the company's crypto trading platform, as the sole front-end engineer: 5 surfaces (AMM, CLOB, perpetuals, token launchpad, portfolio) taken from zero to a public testnet with over 1 million users in under a year.
- Built the internal design system with 20+ Storybook components.
- Implemented wallet login, session handling, and transaction flows with Privy and Viem.
- Built real-time portfolio and trading UIs over WebSocket streams for balances, PnL, positions, and order execution, improving Core Web Vitals on trading screens.
- Used Codex and Claude Code for scaffolding, refactoring, and tests while keeping front-end coverage above 90% with Vitest.
Software Engineer, Frontend
Coinbase
- Built accessible (WCAG), cross-browser sign-in flows for 200,000 daily users, with OAuth for Apple, Google, and Ethereum wallets.
- Led Unified Signup 2.0, A/B-testing new sign-in and sign-up flows for Apple and Google behind feature flags, which lifted signup conversion by 35%.
- Cut load times in key authentication flows by 20% through Core Web Vitals work on rendering and caching.
- Shipped an App Switcher across Help Center, Tracer, and Commerce with i18n and Amplitude analytics, raising cross-product engagement by 0.45%.
- Reviewed code, wrote RFCs for a Turborepo monorepo, and interviewed front-end engineering candidates.
Software Engineer
Tech6
- Built and maintained a real estate platform for 3,000 users with React, TypeScript, and GraphQL.
- Designed and built an internal design system used across 3 platforms, and supported the redesign of the main website.
- Built automated invoice generation for transaction participants, replacing a manual process for every transaction.
Junior Software Engineer
Todobit Sistemas
- Developed and maintained Doutor Fly, a work safety request system, as one of 3 developers working across PHP (Laravel) and JavaScript.
- Built new modules for the platform end to end, from the Laravel back end to the JavaScript front end.
- Fixed bugs across the stack in a legacy codebase, keeping the system stable for its clients.
- Contributed to other client projects at the software house with Angular and Node.js.
Project History
Crypto Trading Platform for 1M+ Testnet Users
http://www.gte.xyzCoinbase Sign-up Redesign That Lifted Conversion 35%
Home Navigation Redesign for NG.cash's App
Real Estate Web Application
https://www.fathomrealty.com/The back end was developed using C# and Postgres and front end using React, TypeScript, and Antd.
Education
Bachelor's Degree in Computer Science
University of the Itajaí Valley (Univali) - Itajai, Santa Catarina, Brazil
Skills
Libraries/APIs
React, Antd, REST APIs, React Testing Library, Node.js, Wagmi, React Hook Form, WebGL, React Query, Zod
Tools
Git, GitHub, Webpack, Shadcn, Claude Code, Claude, Vitest, AWS Cloud Development Kit (CDK), GitLab CI/CD, Sentry
Languages
TypeScript, HTML, CSS, JavaScript, GraphQL, Sass, PHP, SQL, C#
Frameworks
Next.js, Tailwind CSS, Jest, Cypress, Redux, React Native, Angular, Express.js, Laravel
Paradigms
Agile Software Development, REST API Architecture, REST, Object-oriented Programming (OOP), Microfrontends, Model Context Protocol (MCP)
Platforms
Docker, Amazon Web Services (AWS), Contentful, Azure, Vercel, PostHog, AWS Lambda
Storage
MySQL, Databases, Datadog, PostgreSQL
Other
Front-end, Front-end Development, OAuth, Authentication, Finance, Pixel Perfect, User Experience (UX), User Interface (UI), Server-side Rendering (SSR), APIs, Architecture, Design Systems, Front-end Architecture, Storybook, UI Components, React Hooks, Responsive UI, Full-stack, Viem, Privy, Web3, Monorepos, OpenID Connect (OIDC), CI/CD Pipelines, GitHub Actions, Core Web Vitals, Fintech, Performance Optimization, Supabase, Single Sign-on (SSO), Agentic AI, Generative Artificial Intelligence (GenAI), Minimum Viable Product (MVP), Prompt Engineering, Product Management, Rive, Web Content Accessibility Guidelines (WCAG), Artificial Intelligence (AI), Cursor AI, OpenAI, AI Tools, Zustand, WebSockets, Amplitude, Vite, Internationalization, Feature Flags, A/B Testing, Turborepo, Full-stack Development, Decentralized Finance (DeFi), QR Codes
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