Web Application Development
Custom-Built Web Applications That Solve Real Problems
Off-the-shelf software gets you 80% of the way there. We build the other 20% — the custom logic, integrations, and workflows that make your business actually run. From WordPress plugins to full SaaS platforms, we deliver production-ready web applications built on modern, maintainable stacks.
Every application ships responsive, accessible, secure, and documented. No throwaway prototypes — production code from day one.
What We Build
WordPress Plugin Development
Custom WordPress plugins that extend your site’s functionality without the bloat of generic marketplace plugins. Built with proper WordPress coding standards, REST API integration, and admin panel UIs.
We’ve built:
- Content automation plugins with OpenAI integration
- Custom WooCommerce extensions for subscription billing
- Stripe payment integration with tiered access control
- Auto-update systems with license validation
- Scheduled task systems using WordPress Cron
Why custom over off-the-shelf:
- No unnecessary features slowing down your site
- No conflicts with other plugins
- Full control over updates and security patches
- Tailored to your exact business logic
SaaS Platform Development
End-to-end Software as a Service platforms with multi-tenant architecture, subscription billing, user management, and API access. We handle the entire stack from database schema to payment processing.
Key capabilities:
- Multi-tenant data isolation (row-level or schema-level)
- Stripe subscription billing with tiered pricing
- User authentication via OAuth 2.0, JWT, or API keys
- Admin dashboards with real-time analytics
- Webhook-based event systems
- Rate limiting and usage metering
- API documentation with OpenAPI/Swagger
⚡ API Development
RESTful and GraphQL APIs built for performance, developer experience, and reliability. Whether you need a backend for a mobile app, a microservice for an internal tool, or a public API for third-party integrations.
What we deliver:
- FastAPI (Python) or Express (Node.js) backends
- Auto-generated OpenAPI documentation
- Authentication and authorization middleware
- Input validation and error handling
- Database integration with SQLAlchemy, Prisma, or Sequelize
- Automated testing with pytest or Jest
- Versioned endpoints for backward compatibility
️ Frontend Development
Modern, responsive user interfaces built with component-based architectures. We deliver pixel-perfect implementations that work across browsers and devices.
Technologies:
- React with TypeScript — dynamic SPAs and dashboards
- Next.js — server-side rendered applications with SEO optimization
- Tailwind CSS — utility-first styling for rapid development
- WordPress Block Editor — custom Gutenberg blocks
- Responsive design — mobile-first, accessible, WCAG 2.1 compliant
What we focus on:
- Performance (sub-2-second Largest Contentful Paint)
- Accessibility (ARIA labels, keyboard navigation, screen reader support)
- SEO (structured data, meta tags, semantic HTML)
- User experience (intuitive navigation, clear CTAs, minimal friction)
Third-Party Integrations
Connect your application to the tools your business already uses. We integrate APIs from payment processors, CRMs, email services, analytics platforms, and more.
Common integrations:
| Service | Use Case |
|---|---|
| Stripe | Payment processing, subscriptions, invoicing |
| SendGrid / Mailgun | Transactional email |
| Twilio | SMS notifications, voice |
| Salesforce | CRM synchronization |
| Slack | Team notifications, chatbots |
| Google Analytics | Usage tracking and reporting |
| OpenAI | AI-powered features |
| AWS S3 | File storage and CDN |
Our Development Process
Requirements → Architecture → Build → Ship
We follow a structured process that keeps projects on track and on budget:
1. Requirements Gathering
We work with you to define user stories, data models, and acceptance criteria. No ambiguity — every feature is scoped before a line of code is written.
2. Technical Architecture
System design document covering: tech stack selection, database schema, API contracts, infrastructure requirements, and security model. Reviewed and approved before development begins.
3. Sprint-Based Development
2-week agile sprints with demos at the end of each cycle. You see working software early and often, with the ability to adjust priorities as you learn.
4. Quality Assurance
- Automated unit and integration tests
- Manual testing for UX and edge cases
- Security review (OWASP Top 10)
- Performance testing under load
- Cross-browser and device testing
5. Deployment & Launch
Production deployment with monitoring, alerting, and runbook documentation. We don’t just “throw it over the wall” — we ensure a smooth launch.
Project Examples
E-Commerce Automation Platform
Challenge: Client needed automated content generation for 12 niche WordPress sites.
Solution: Custom WordPress plugin + FastAPI backend with:
- AI content generation via OpenAI
- Scheduled publishing (daily/weekly)
- Tiered subscription billing via Stripe
- Self-hosted search engine integration
- Prometheus/Grafana monitoring
Result: 12 sites running on autopilot with consistent, scheduled content.
Internal Operations Dashboard
Challenge: Client’s team was juggling 6 different tools to manage daily operations.
Solution: Unified React dashboard with:
- Single sign-on via OAuth 2.0
- Real-time data from 4 API integrations
- Custom reporting and export functionality
- Role-based access control
Result: One tool instead of six. 3 hours saved per employee per day.
Legacy System Migration
Challenge: 10-year-old PHP monolith with no tests, no documentation, and growing downtime.
Solution:
- Incremental migration to FastAPI + React
- Database migration from MySQL to PostgreSQL
- Docker containerization with CI/CD
- Comprehensive test suite added during migration
Result: 99.9% uptime, 4x faster page loads, and a codebase the team can actually maintain.
Pricing
| Project Type | Starting At | Typical Timeline |
|---|---|---|
| WordPress plugin (custom) | $3,000 | 2–4 weeks |
| API backend | $5,000 | 3–6 weeks |
| Full SaaS platform (MVP) | $15,000 | 6–12 weeks |
| Frontend application | $5,000 | 3–6 weeks |
| Third-party integration | $1,500 | 1–2 weeks |
| Legacy migration | $10,000+ | 4–12 weeks |
Fixed-price projects. Milestone-based payments. No hourly billing.
Ready to Build Your Application?
Tell us what you need. We’ll tell you how we’d build it, how long it’ll take, and what it’ll cost — for free.
Schedule a Free Consultation →
Or email: hello@mobstacker.com
MobStacker — Custom software that fits your business, not the other way around.