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Web Development

Web Applications
Built for Modern Browsers

The web has evolved from static pages to powerful application platforms. We build lightning-fast, secure, and SEO-optimized web experiences that convert.

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The Web Performance Gap

Is Your Website
Leaking Potential Revenue?

Poor user experience on the web directly correlates to loss of trust and traffic. We identify and solve your digital friction.

Slow Initial Load

Every second of delay reduces conversion rates by 7%. We build for sub-second performance using modern caching.

Poor Mobile Experience

Search engines penalize desktop-only layouts. We prioritize mobile-first design for maximum reach.

Security Vulnerabilities

Expired SSLs or unpatched plugins are an open invitation to hackers. We build secure, hardened web shells.

Invisible to Search

Technical SEO issues often hide great content from Google. We ensure your web app is perfectly crawlable.

Inability to Scale

A website that crashes under heavy traffic is a failure. We use global CDNs and edge functions for infinite scale.

Compliance Issues

Ignoring ADA accessibility or GDPR privacy laws can lead to legal action. We ensure your web app is compliant.

Our Web Expertise

Web Solutions

From interactive portfolios to complex enterprise dashboards, we deliver performance on every browser.

React & Next.js Dev

Dynamic, component-based frontends with Server-Side Rendering (SSR) for perfect SEO and speed.

Full-Stack JS (MERN)

End-to-end JavaScript development for seamless communication between your frontend and backend.

Custom SaaS Platforms

Secure multi-tenant architectures with integrated subscriptions, user roles, and data visualization dashboards.

Enterprise E-commerce

Custom storefronts built for high-volume transactions with integrated headless CMS for easy management.

Progressive Web Apps

Web apps that feel like mobile apps, complete with offline mode, push notifications, and home screen installation.

Speed & Performance Audits

Comprehensive optimization of images, code splitting, and server response times for perfect Core Web Vitals.

Web Technology Stack

Modern frameworks and utilities for the modern web.

Frontend Core

  • React / Next.js
  • Vue / Nuxt.js
  • TypeScript
  • Semantic HTML5

Styling & UI

  • Tailwind CSS
  • SCSS / SASS
  • Framer Motion
  • Headless UI

State & Data

  • GraphQL / Apollo
  • Redux / Zustand
  • React Query
  • Supabase / Prisma

Deployment & Edge

  • Vercel / Netlify
  • Cloudflare Workers
  • AWS S3 & CloudFront
  • GitHub Actions

Performance

  • WebP / AVIF Optimization
  • Code Splitting
  • Brotli Compression
  • Core Web Vitals

Headless CMS

  • Contentful
  • Strapi / Sanity
  • Ghost CMS
  • Headless WordPress

QA & Testing

  • Cypress / Playwright
  • Jest / Vitest
  • Sentry Monitoring
  • Axe Accessibility

Compliance

  • GDPR / CCPA Ready
  • WCAG 2.1 Compliance
  • OWASP Top 10
  • Privacy Policy Auto-gen

Why Trust Constelly for
Web Engineering?

We don't just build websites; we build business tools. Our engineering team combines deep technical expertise with a keen understanding of marketing and user psychology.

Security-First Culture

Everything we build is hardened against the OWASP Top 10 threats from the first day.

Performance Obsessed

We target 90+ Lighthouse scores across the board for superior SEO and user retention.

Maintainable Codebase

We write clean, documented TypeScript that your internal team can actually work with.

300+

Web Projects Launched

30%

Avg conversion increase

0

Critical Security Breach

24/7

Server Monitoring

Frequently Asked Questions

A website is primarily informational and static, while a web app is interactive and performative. Web apps often have user accounts, databases, and complex logic (like a CRM or a SaaS portal).
Next.js provides Server-Side Rendering (SSR) and Static Site Generation (SSG), which are critical for SEO and initial load performance. It allows us to build complex apps that still rank high on search engines.
Basic business websites start at $5k, while complex web applications and SaaS platforms typically range from $15k to $100k+ depending on the feature set and integration requirements.
100%. We employ responsive design as a standard. Your web app will function perfectly on desktops, tablets, and smartphones, with layouts that adapt to any screen size.
A simple project takes 4-6 weeks. A complex SaaS platform or enterprise dashboard can take 3-6 months. We follow an agile process with bi-weekly updates and review sessions.
Yes. We can manage your cloud infrastructure on platforms like Vercel, AWS, or Azure. We also offer maintenance plans for security updates, bug fixes, and feature additions.
Technical SEO is the process of optimizing your website's infrastructure so search engines can easily crawl and index your content. This includes sitemaps, robots.txt, schema markup, and loading speed.
Yes. We specialize in legacy migration�taking an old, slow website and rebuilding it with clean code and modern aesthetics without losing your existing SEO value.
Yes, we follow WCAG 2.1 guidelines to ensure your web app is accessible to all users, including those with visual or motor impairments, which also helps with SEO.
Our modular code architecture makes it easy to scale. We use component-based development which allows us to add new sections, features, or integrations without breaking your existing site.

Create Powerful Web Experiences

Build responsive, high-performance web applications using modern frameworks. Deliver engaging user experiences across all devices.

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