Johnson Pasala
Senior Full Stack Developer | Mern | Next.js | React Native
Johannesburg,GP
Summary
- Strategic FinTech Engineer: Over 6 years of experience specializing in "Generation 3" ticketing and payment platforms. Expert in building high-conversion, low-latency systems handling millions of Euros in transactions.
- Full Stack Architecture: Deep expertise in the MERN Stack (MongoDB, Express, React, Node.js) and Java Spring Boot, focusing on headless API architectures and microservices.
- Performance & Scale: Proven track record of maintaining 99.99% uptime while managing 10,000+ concurrent users during high-pressure "ticket drops."
- Security & Compliance: Specialist in POPIA (South Africa) and global financial regulations (GDPR/PCI-DSS), implementing idempotent APIs and secure RBAC.
- Conversion-Centric Development: Skilled in engineering 1-click ordering systems and AI-driven automation that increases sales conversion by up to 21%.
Overview
7
7
years of professional experience
2
2
Languages
Work History
Senior Full Stack Developer
Billetto
09.2024 - 11.2025
- Conversion-Optimized Checkout Engine: Engineered a '1-click' checkout workflow and address auto-complete features.
- High-Concurrency Seat Management: Architected a real-time venue mapping system using WebSockets, allowing thousands of users to reserve seats simultaneously without data collisions.
- Uptime Excellence: Optimized the Node.js/MongoDB backend to sustain 99.99% uptime during extreme traffic surges, ensuring sub-second response times for booking APIs.
- AI-Driven Automation: Developed AI-powered event description generators and automated 'abandoned basket' email triggers to recover lost revenue.
- Fraud & Bot Mitigation: Implemented advanced rate-limiting and bot-detection layers to ensure 'fair play' during high-demand event launches.
- Audit & Compliance: Designed an immutable internal audit log for transaction state changes (Pending → Settled → Refunded) to meet European and South African financial standards.
- Reviewed code, debugged problems, and corrected issues.
- Managed version control systems like Git for tracking code changes, enabling streamlined collaboration among team members.
- Championed adoption of Agile methodologies within the development team resulting in increased efficiency during project delivery cycles.
- Implemented continuous integration and deployment pipelines to automate code testing, validation, and deployment processes.
- Reduced application bugs by implementing rigorous unit testing frameworks alongside comprehensive test coverage.
- Mentored junior developers in adopting industry-standard practices while fostering a collaborative learning environment within the team.
- Collaborated with fellow engineers to evaluate software and hardware interfaces.
- Proved successful working within tight deadlines and a fast-paced environment.
- Conducted detailed API testing using Postman, verifying system integrity and data flow between frontend and backend systems.
Full Stack Developer
InsaTech Solutions
10.2021 - 09.2024
- Enterprise RBAC Architecture: Designed a granular Role-Based Access Control system for complex admin panels, managing permissions for users, advisors, and moderators.
- Performance Refactoring: Optimized React frontend components through code-splitting and memoization, leading to a 40% reduction in Initial Page Load (IPL) times.
- Subscription & Billing: Built an automated recurring billing module for SaaS clients, integrating subscription status with feature-gating logic.
- Developed functional databases, applications and servers to support websites on back-end.
- Integrated third-party APIs to enhance functionality and improve overall user experience on web platforms.
- Developed unit test cases for testing and automation.
- Reviewed code, debugged problems, and corrected issues.
- Collaborated with cross-functional teams to design, develop, and launch new features for web applications.
- Developed responsive web designs, ensuring compatibility across various devices and browsers.
- Coordinated deployments of new software, feature updates and fixes.
- Proved successful working within tight deadlines and a fast-paced environment.
- Conducted data modeling, performance and integration testing.
- Facilitated seamless integration efforts through diligent API testing and validation processes.
MERN Stack Developer
Aarc Technologies
08.2018 - 09.2021
- Data Visualization Dashboards: Built dynamic reporting tools using React and D3.js to visualize complex financial datasets for stakeholders.
- API Standardization: Refactored legacy REST APIs into a unified, documented Headless API architecture, improving developer onboarding time by 30%.
- Database Optimization: Optimized MongoDB aggregation pipelines to handle large-scale datasets, reducing query execution time by 50%.
- Implemented CI/CD pipelines for automated testing and deployment processes, increasing efficiency in the software release cycle.
- Developed reusable code libraries to optimize development time and reduce redundancy within projects.
Education
Bachelor's Degree - Commmerce With Computers
Osmania University
Hyderabad, India 04.2001 -
Skills
Frontend: React
Nextjs
React Native
Redux
Zustand
TypeScript
Tailwind CSS
Backend: Nodejs
Express
WebSockets (Real-time Seating)
Database: SQL
PostgreSQL
MongoDB
MySQL
Firebase
FinTech: Stripe/PayPal/Klarna Integration
Multi-currency Payouts
Refund Orchestration
Security: JWT
HTTP-only Cookies
RBAC
OAuth2
API Encryption
Bot Mitigation
DevOps: Docker
CI/CD
GitHub Actions
Cloud Infrastructure
Audit Logging
API integration
Backend development
Frontend development
Cross-platform development
Mobile app development
JavaScript programming
CSS proficiency
HTML expertise
Web programming
Timeline
Senior Full Stack Developer
Billetto
09.2024 - 11.2025
Full Stack Developer
InsaTech Solutions
10.2021 - 09.2024
MERN Stack Developer
Aarc Technologies
08.2018 - 09.2021
Bachelor's Degree - Commmerce With Computers
Osmania University
04.2001 -
Core Competencies
React, Next.js, React Native, Redux, Zustand, TypeScript, Tailwind CSS, Node.js, Express, Java, Spring Boot, WebSockets (Real-time Seating), SQL, PostgreSQL, MongoDB, MySQL, Firebase, Stripe/PayPal/Klarna Integration, Multi-currency Payouts, Refund Orchestration, JWT, HTTP-only Cookies, RBAC, OAuth2, API Encryption, Bot Mitigation, Docker, CI/CD, GitHub Actions, Cloud Infrastructure, Audit Logging
Strategic Technical Projects
- Spikevine, The Challenge: Automating campaign budgets and influencer payouts across different regions., The Solution: Built a React/Node.js platform with a custom design system and an integrated ledger for tracking campaign spending in real-time., Outcome: Successfully connected thousands of brands and influencers with 100% payment accuracy.
- LearnEdge, The Challenge: Providing on-demand access to high-resource remote labs while preventing unauthorized usage., The Solution: Developed a 'Timed-Access' gateway using Java and Node.js. Integrated an automated session-killer that terminated lab instances at the end of paid periods., Impact: Reduced server infrastructure costs by 15% through efficient resource recycling.
- VOIP Management & Security Suite, Technical Stack: Node.js, MongoDB, REST APIs., Core Function: Engineered a secure credential management system for VOIP providers, featuring encrypted data storage and session-based access logs.
Legal Work Authorization
Authorized to work in South Africa under a Critical Skills Visa
Personal Information
- Work Permit: Critical Skills Visa
- Availability: Immediate, South Africa
- Visa Status: 2024 To 2029