Web Systems
SSR and SPA architectures with green Core Web Vitals (LCP < 2.5 s, INP < 200 ms, CLS < 0.1 measured with Lighthouse), from API design to deployment.
Hi, I'm Carlos
Fullstack Developer
Carlos is a fullstack developer specialized in high-performance SSR web systems and native apps for Android (Kotlin) and iOS (Swift).
He works remotely from [VERIFY: city, country] for international clients, with [VERIFY: N] years of experience shipping production software with TypeScript, Astro, Svelte and Node.js. He is available for freelance projects and remote full-time roles, and replies to inquiries within 24 hours.
- Years of experience
- [VERIFY: N]+
- Apps published on stores
- [VERIFY: N]
- Web projects in production
- [VERIFY: N]
About me
Code with purpose, design with intent
Carlos [VERIFY: last name] is a fullstack developer based in [VERIFY: city, country], working fully remote since [VERIFY: year]. His core stack is TypeScript, Astro, Svelte and Node.js on the web, plus Kotlin (Jetpack Compose) and Swift (SwiftUI) on mobile. He has shipped [VERIFY: N] web systems and [VERIFY: N] mobile apps published on Google Play and the App Store, prioritizing Core Web Vitals, WCAG 2.1 accessibility and maintainability.
Android & iOS Apps
Native apps built with Kotlin/Jetpack Compose and Swift/SwiftUI, published and maintained on Google Play and the App Store.
Performance & UX
Performance-budget driven optimization: low SSR TTFB, minimal JS per page, accessibility and purposeful motion.
Technical leadership
Team mentoring, demanding code reviews and architecture decisions built to scale.
Skills
Tech stack
Technologies used in production, with years of experience and real context instead of self-assessed percentages.
Frontend
- TypeScript
[VERIFY: N] years · daily use in production
- Astro
[VERIFY: N] SSR projects shipped
- Svelte
[VERIFY: N] years · apps and islands in production
- React
[VERIFY: N] years · SPAs for banking and retail
- Tailwind CSS
This portfolio's design system and [VERIFY: N] projects
Backend
- Node.js / Bun
[VERIFY: N] years · APIs and SSR in production
- PostgreSQL
[VERIFY: N] years · schema design and query tuning
- GraphQL / REST
Public and internal APIs for [VERIFY: N] products
- Redis
Caching and queues in high-traffic systems
- Docker / K8s
CI/CD and container deployments since [VERIFY: year]
Mobile
- Kotlin / Jetpack Compose
[VERIFY: N] apps published on Google Play
- Swift / SwiftUI
[VERIFY: N] apps published on the App Store
- Flutter
[VERIFY: N] cross-platform projects
- React Native
[VERIFY: N] hybrid apps maintained
- Mobile CI/CD
Fastlane pipelines for both stores
TypeScript Astro Svelte React Tailwind CSS Node.js Bun PostgreSQL GraphQL Docker Kotlin Jetpack Compose Swift SwiftUI Flutter AWS Redis Kubernetes TypeScript Astro Svelte React Tailwind CSS Node.js Bun PostgreSQL GraphQL Docker Kotlin Jetpack Compose Swift SwiftUI Flutter AWS Redis Kubernetes
Projects
Selected work
A sample of web systems and mobile apps in production. Filter by category.
- ★ Featured Fullstack
FinTrack Suite
Personal finance SaaS platform with real-time dashboards, 50k transactions/min processing and bank synchronization.
- Astro
- Svelte
- Node.js
- PostgreSQL
- Redis
- ★ Featured Mobile
FitPulse
Native fitness app for Android and iOS with biometric tracking, AI-powered plans and 100k+ downloads on both stores.
- Kotlin
- Jetpack Compose
- SwiftUI
- Firebase
- ★ Featured Web
Commerce Engine
Headless e-commerce engine with SSR, 2-step checkout and perfect Core Web Vitals. +40% conversion for retail clients.
- Astro SSR
- TypeScript
- Stripe
- Tailwind
- Fullstack
MediBook
Multi-clinic medical appointment system: smart scheduling, push reminders and integrated telemedicine.
- SvelteKit
- GraphQL
- PostgreSQL
- WebRTC
- Mobile
UrbanRide
Urban mobility app with real-time maps, geospatial driver matching and in-app payments.
- Swift
- Kotlin
- Node.js
- MongoDB
- Socket.io
- Web
DevMetrics
Open source DORA metrics dashboard for engineering teams, with GitHub, GitLab and Jira integrations.
- Astro
- Svelte
- D3.js
- Bun
Career
Professional experience
-
Senior Fullstack Engineer
2023 — PresentTechNova Labs
I lead the development of a B2B SaaS platform used by 200+ companies. I designed the migration to Astro SSR cutting TTFB by 60% and mentor a team of 5 developers.
- Astro
- Svelte
- Node.js
- PostgreSQL
- AWS
-
Mobile Lead Developer
2021 — 2023Appsmiths
Owned native Android/iOS apps with 500k+ active users. Introduced a modular architecture with Compose and SwiftUI, cutting release time from 3 weeks to 4 days.
- Kotlin
- Swift
- Jetpack Compose
- SwiftUI
- Fastlane
-
Fullstack Developer
2019 — 2021Digital Factory
Built custom web systems for banking and retail clients: REST/GraphQL APIs, SPA frontends and full CI/CD pipelines.
- React
- Node.js
- GraphQL
- Docker
- MySQL
FAQ
Frequently asked questions
Direct answers to what clients and recruiters ask the most.
What services does Carlos offer?
Fullstack development of SSR web systems with Astro, Svelte, TypeScript and Node.js, plus native Android (Kotlin/Jetpack Compose) and iOS (Swift/SwiftUI) apps, including publishing and maintenance on Google Play and the App Store.
Is he available for freelance or full-time work?
Yes. He is available for freelance projects, collaborations and fully remote full-time positions, and replies to inquiries within 24 hours.
Where does he work from?
He works remotely from [VERIFY: city, country] (GMT[VERIFY: ±X]) for international clients, in Spanish and English.
What is his core tech stack?
Web: TypeScript, Astro, Svelte, Node.js/Bun, PostgreSQL and GraphQL. Mobile: Kotlin with Jetpack Compose and Swift with SwiftUI.
Contact
Shall we build something together?
I'm open to freelance projects, collaborations and full-time positions. Write me and I'll get back to you within 24 hours (GMT[VERIFY: ±X]).