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Better call SalehPKT · UTC+5

Saleh Ahmed · Full-Stack Engineer

Product-minded full-stack engineer with 5 years of experience building and deploying web and mobile products end to end: e-commerce, booking and escrow marketplaces, and production LLM integrations.

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Years engineering
5+
1st-month sales
£10K+
Tests per release
842+
Based in
Karachi, PK

Five years of engineering, high-volume platforms, and products that scaled.

I work across TypeScript, React, Next.js, React Native, Node.js, PostgreSQL and Supabase, designing the APIs, databases, payment flows and cloud infrastructure behind a product and taking it from first schema to App Store and Google Play launch.

At Brussel Lake Paragon, a 15-person London digital agency, I build e-commerce, booking and escrow marketplace products end to end. Tottenham Wheels generated £10K+ in first-month online sales, and Zovah and Zaroba launched on the App Store and Google Play with Stripe Connect and Paystack escrow behind them.

My engineering approach focuses on clear fundamentals: normalized relational schemas, strict TypeScript types, auditable payment logic, and releases gated on end-to-end tests.

Selected proof

PostgreSQL tables with RLS
26
Zaroba's escrow marketplace schema, with row-level security and Paystack escrow for buyer payments. Read the case study
Security requirements
33
A roadmap from auditing an AI ad platform: a browser-exposed OpenAI key, unmetered LLM endpoints and unverified payments.
API security flaws closed
8
Toli, including a mass-assignment bug that let users set their own reputation scores. Read the case study
Trades reconciled to the cent
300
P&L, win rate and profit factor from a FIFO engine and Python pipeline over TradeStation and Charles Schwab data.

Toolbox

Frontend & Mobile

  • TypeScript
  • JavaScript
  • React
  • Next.js
  • React Native (Expo)
  • HTML/CSS
  • React Query
  • Zustand
  • Redux

Backend & APIs

  • Node.js
  • NestJS
  • Express
  • Python
  • GraphQL
  • REST APIs
  • Microservices

Data & Cloud

  • PostgreSQL (PostGIS)
  • SQL
  • Supabase
  • MongoDB
  • Prisma
  • Redis
  • AWS
  • Docker
  • Git
  • GitHub Actions (CI/CD)

Testing & Payments

  • Vitest
  • Jest
  • Playwright
  • Stripe Connect
  • Paystack
  • Payaza

AI

  • OpenAI API (LLMs/GPT)
  • Model Context Protocol (MCP)
  • Cursor
  • Claude Code

Where I have worked

03 engagements

  1. 01

    Brussel Lake Paragon

    · 15-person London digital agencyCurrent

    Full Stack Developer · Remote, UK

    • Generated £10K+ in first-month online sales for Tottenham Wheels by building its Next.js and TypeScript web application end to end, including e-commerce, workshop bookings, POS, and administrative tools.
    • Launched Zovah on the App Store and Google Play after designing and developing its React Native and TypeScript mobile application, enabling customers to discover, book, and pay UK beauty and events providers through Supabase serverless functions and AWS S3.
    • Next.js
    • React Native
    • TypeScript
    • PostgreSQL
    • Supabase
    • Stripe Connect
    • Paystack
    • GitHub Actions
    Feb 2024 – Present
  2. 02

    Self-Employed

    Full Stack Developer · Remote, UK and international clients

    • Built a trading journal that reconciled P&L, win rate, and profit factor to the cent across 300 trades using a FIFO engine and Python pipeline for TradeStation and Charles Schwab data.
    • Discovered and neutralized a browser-exposed OpenAI key in an AI advertising platform, then converted its unmetered LLM endpoints and unverified subscription payments into a 33-requirement security roadmap by auditing its React, Express, and Supabase codebase.
    • Next.js
    • Supabase
    • React
    • Express
    • Python
    • Security audits
    Jul 2022 – Jan 2024
  3. 03

    B-DIGI International

    · Digital agency

    Frontend Developer · Karachi, Pakistan

    • Developed and deployed responsive front-end interfaces, reusable React components and REST API integrations using JavaScript, HTML5, CSS3, Redux, Docker and CI/CD pipelines, reducing page-load times and improving user satisfaction.
    • React
    • JavaScript
    • HTML5/CSS3
    • Redux
    • Docker
    • CI/CD
    Jun 2021 – Jun 2022
Education Virtual University of Pakistan · B.S. in Business and Information Technology CGPA 3.63 / 4.0 June 2025

Things I have
actually shipped.

Full-stack web and mobile products: marketplaces, booking platforms, fintech workflows, and operations panels.

09 projects

What I build.

Full-stack web applications, mobile products, and transactional backend services. Available for focused architectural milestones or end-to-end product development.

  1. 01

    Web Applications

    Full-stack web applications built with Next.js, React, and TypeScript, backed by typed APIs and normalized database schemas.

    • Next.js 16 / React 19 App Router
    • REST & GraphQL API design
    • Prisma / PostgreSQL / MongoDB schemas
    • Auth & role-based permissions
  2. 02

    Mobile Apps (iOS & Android)

    Cross-platform iOS and Android applications built with React Native and Expo, deployed to both app stores from a single codebase.

    • React Native & Expo development
    • Offline synchronization & caching
    • Push notifications & deep linking
    • App Store & Google Play deployments
  3. 03

    Fintech, Payments & Escrow

    Payment workflows using Stripe Connect, Paystack, and Payaza, covering escrow states, automated split payouts, and signed webhook verification.

    • Stripe Connect custom commissions
    • Escrow wallet & dispute lifecycles
    • Signed webhook refund verification
    • Multi-currency payment gateways
  4. 04

    Backend Systems & APIs

    Server-side services built on Node.js, NestJS, and Express, featuring PostGIS geospatial queries, Redis caching, and WebSocket feeds.

    • NestJS & Node.js microservices
    • PostGIS geospatial location queries
    • WebSocket real-time chat & notifications
    • API security auditing & rate limiting
  5. 05

    CI/CD & Quality Engineering

    Automated delivery pipelines with GitHub Actions and Docker, gating deployments with comprehensive Playwright E2E and Jest suites.

    • Playwright end-to-end test suites
    • Jest unit & integration tests
    • GitHub Actions & Docker pipelines
    • Expo Application Services (EAS) builds
  6. 06

    AI Integration & Workflows

    Integrating LLMs into production apps with security, token budgeting, streaming completions, and 3D conversational avatars.

    • OpenAI API & LLM integration
    • Streaming responses & conversational history
    • API key security & usage metering
    • 3D avatar lip-sync rendering layer

Notes from production.

Write-ups of problems I hit in shipped work, with the numbers behind each fix.

All writing
  1. · 4 min readFixing a 6-second LCP caused by a hero fade-in animationMy portfolio's hero text stayed invisible until React hydrated. I moved its entrance to CSS and cut mobile LCP from 6s to 1.3s, after one false start.

Got something
that needs
building?

Have a project, a deadline, or an architecture question? Email me directly. If it is not a fit, I will tell you upfront.

dev.salehahmed@gmail.com

Open to full-time roles & selected contractsKarachi, Pakistan