Rostislav Sevastianov
React and SwiftUI developer
- Based in Barcelona
- Available remotely across Europe
- English, Spanish, and Russian
Structure-led websites for businesses that want clarity, speed, and presence.
Websites built
with structure
Computer Science student. Programming since 2021.
Performance-focused websites for growing businesses.
About
Design discipline paired with developer thinking.
I am Rostislav Sevastianov, a Barcelona-based developer focused on high-performance websites and polished digital products that feel clear, fast, and intentional.
I approach websites like systems, not just surfaces. The goal is to create work that looks clean, communicates quickly, and stays technically solid once real content, growth, and business needs start putting pressure on it.
Being early in my freelance path is an advantage here. I bring current tools, a lot of care for detail, and the kind of focus that comes from wanting every build to be strong enough to speak for itself.
Performance-Obsessed
Fast loading, stable interactions, and a site that feels light from the first scroll.
Results-Driven
Every design choice should support clarity, trust, and a stronger business outcome.
Transparent Process
Clear updates, visible progress, and shared decisions instead of surprises late in the build.
React
TypeScript
Next.js
SwiftUI
Firebase
Core Web Vitals
Services
Landing pages, apps, and product surfaces built with clarity.
The service mix is intentionally focused: sharp websites, capable web applications, and SwiftUI builds where native iOS actually makes sense.
01
Custom Websites
Business sites and landing pages with clear messaging, responsive layouts, and strong performance fundamentals from the start.
- Landing pages and portfolio sites
- Content-focused redesigns
- SEO-ready, performance-first builds
02
Web Applications
Product-style interfaces for dashboards, tools, and early SaaS ideas that need more than a marketing page.
- Dashboards and internal tools
- Authenticated user flows
- Frontend architecture that can grow
03
iOS App Development
SwiftUI interfaces for prototypes and focused iOS products where native performance and platform feel matter.
- SwiftUI product builds
- Prototype to polished interface work
- UI systems with native feel
Need something more custom or a hybrid of these? We can scope the right format together.
Discuss the projectPricing & Add-Ons
Clear starting points for the core builds, plus the extra services that help them perform.
The idea is to keep scope visible from the start. These are guide prices, not rigid packages, so the final quote always adjusts to the actual brief and complexity.
Core Builds
Website Pricing
Landing Page
A focused one-page build with clear structure, conversion-driven messaging, responsive design, and performance baked in from the start.
From €900
Request this buildMulti-page Website
A structured business website with multiple pages, a stronger content hierarchy, and a system that feels cohesive across the whole site.
From €1,600
Request this buildWeb App MVP
Product-style interfaces for dashboards, internal tools, or early SaaS ideas that need user flows, data structure, and a UI that can scale.
From €2,800
Discuss the productiOS App Build
SwiftUI-based iPhone product work for prototypes or focused apps where native feel, polished interactions, and performance matter.
From €2,400
Scope the appGrowth Support
Additional Services
SEO Foundations
Technical cleanup, metadata, page structure, performance checks, and content alignment so the site starts from a stronger organic base.
From €250
Add SEO supportGoogle Business Profile Optimization
A cleaner local presence through profile tuning, offer clarity, category setup, visual polish, and a stronger Google Maps first impression.
From €180
Improve local visibilityAI Product Visuals
High-quality generated imagery for products, brand scenes, or campaign assets when stock photography is not enough and custom shoots are too heavy.
From €140
Request visualsAI Video Production
Short-form branded visuals and motion pieces designed for web, social, or campaign use when you need momentum without a full production crew.
From €260
Request videoOngoing Site Support
Content updates, technical fixes, layout refinements, and smaller growth improvements for teams that want consistent support after launch.
From €120
Arrange supportNeed a hybrid scope or a custom retainer? The best fit usually comes from combining a core build with the right support services.
Request a custom quoteSelected Work
Projects framed around utility, clarity, and real product feel.
A mix of product-style builds, polished business surfaces, and interfaces shaped around speed, structure, and practical use.
SevaFinance
A finance tracking interface built around live data, clearer hierarchy, and a dashboard flow that keeps information easy to scan.
View live project
Baltenn Commerce Section
A custom commerce section for the tennis academy that introduces products without losing the clean sports-club identity.
View live project
DevToolKit
A privacy-first toolbox with dozens of client-side utilities, designed to feel fast, dependable, and genuinely useful.
View live project
Baltenn Hero Section
A cleaner opening section for the academy site, built to establish tone quickly and frame the brand with stronger hierarchy.
View live project
Cafeteria Website Concept
An unused client concept that still became a solid showpiece, with custom backgrounds and a warmer presentation style for hospitality work.
View live projectWant a site or product surface with this level of structure and polish?
Start a projectBlog
Writing about frameworks, performance, and practical frontend decisions.
The writing side of the portfolio stays focused on useful topics: choosing tools well, making sites faster, and building with more clarity.
React vs Vue.js: Best Framework for 2025 Projects
A practical comparison of performance, ecosystem maturity, learning curve, and real project fit so the framework choice actually serves the product.
Read articleCore Web Vitals Guide 2025
A grounded walkthrough of LCP, INP/FID, and CLS with concrete ways to improve speed, stability, and rankings without vague advice.
Read articleBlog archive
Browse all writing
Two published articles are already live, with more notes on modern web development, UI systems, and product thinking to follow.
2 published posts and growing
Open blog indexContact
A direct path to start the project conversation.
If you already have the idea in mind, send the outline and I will reply within 24 hours with the best next step, whether that is a proposal, a clearer scope, or a short kickoff call.
Project brief
Direct contact
Reach out directly if you already know what you need or just want to open the conversation without filling the form first.
What happens next
1
I review the brief
I look at the scope, the goal, and where the build needs the most clarity.
2
You get a reply within 24 hours
Usually with the best next step, key questions, and whether a proposal or call makes more sense.
3
We align and start
Once the scope feels right, we move into design direction, build priorities, and delivery.
Available for new projects