Freelance Backend Engineers in Federal Capital Territory

Freelance Backend Engineers in Federal Capital TerritoryFreelance Backend Engineers in Federal Capital Territory

Projects People

Full-Stack Engineer Delivering Secure and scalable Systems

Full-Stack Engineer Delivering Secure and scalable Systems

Cover image for Architected and delivered a semi-decentralized

Architected and delivered a semi-decentralized USDT ↔ KRW trading platform, balancing centralized compliance controls with decentralized transparency to enable secure, real-world crypto–fiat exchange in a regulated market. Co-designed a regulation-friendly transaction flow with product and compliance, enabling secure on-/off-ramp operations tailored to Korean financial regulations and reducing manual review overhead. Led multilingual localization (Korean/English), expanding regional adoption and driving a 40% increase in active users within the first year of launch. Optimized frontend performance and API design, cutting page load time by 35% and improving transaction completion rates through reduced latency and error handling. Owned end-to-end development across React, Node.js, and MongoDB, ensuring production-grade scalability and reliability for high-volume financial transactions with sub-second response times.

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Cover image for WelliRecord - Co-Founder &

WelliRecord - Co-Founder & Full-Stack Systems Engineer Building patient-owned health data infrastructure designed for Africa. I lead the architecture and engineering of a health record platform that allows patients to securely carry their medical history across hospitals, reducing fragmented care and unnecessary repeated tests. Key systems I engineer: Patient-owned health data vaults Provider workflows for queues, triage, and clinical encounters Multi-organization access control for healthcare providers Secure and interoperable health data infrastructure I design and engineer reliable healthcare systems that keep patient data accessible even in low-connectivity environments, helping providers reduce fragmented records, repeated tests, and delays in care. Through strong system design, scalable architecture, and secure data infrastructure, I build solutions that connect healthcare workflows, improve data accessibility, and give organizations the technology they need to deliver better patient care.

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Cover image for Finditor — Engineering in Practice
Built

Finditor — Engineering in Practice Built Finditor to solve a simple but expensive problem: people and businesses have financial data, but often lack the systems to turn that data into clear decisions. As the Full-Stack Systems Engineer, I designed and built the product across the stack from frontend experience and backend architecture to data processing, APIs, database design, security, and infrastructure. The goal isn't just to make software that works. It's to build a system that turns complex financial data into actionable intelligence, while remaining reliable, scalable, and maintainable as usage grows. Finditor is a practical example of how I approach engineering: solve the business problem first, then build the system that can support the solution.

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Cover image for

-> Re-engineered the frontend architecture

-> Re-engineered the frontend architecture by upgrading Next.js and introducing TypeScript, improving application performance by 30% while strengthening type safety and maintainability. -> Integrated frontend features with backend APIs and authentication services, implementing protected routes, role-based access control, dynamic data flows, and API-driven functionality. -> Engineered 5+ core workforce management workflows covering staff scheduling, employee operations, client management, reporting, and administration for the platform. -> Contributed to the platform's PWA and mobile application experience using Capacitor, extending workforce management workflows from desktop web to mobile devices. -> Collaborated closely with backend engineers and product stakeholders to turn evolving requirements into functional product workflows, resolve integration issues, and continuously refine the user experience.

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Backend Engineer(3)

AI engineer building systems for education & security

AI engineer building systems for education & security

Cover image for Excited to share my first

Excited to share my first step into building and shipping in public. Over the past months, I’ve been focused on building systems that sit at the intersection of AI, education, and real-world safety. Two projects I’ve been working on: • BedfordLearn — an AI-powered learning platform that simplifies education for primary and secondary students • White Waters Sentinel — a real-time incident reporting and intelligence platform designed for faster response and better situational awareness Both projects are built around a simple idea: technology should make complex systems easier to understand and act on. I’m currently open to collaborating on AI systems, full-stack platforms, and automation tools that solve meaningful problems. More to come soon.

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Cover image for White Waters Sentinel is a

White Waters Sentinel is a real-time national security and incident reporting platform designed to improve emergency response and operational awareness. It enables citizens and field operatives to report incidents instantly, supports live monitoring of security events, and provides centralized intelligence for faster, data-driven decision-making. The system is built for scalability and nationwide coverage, integrating geospatial data and secure reporting workflows to support coordinated response efforts across multiple agencies and regions.

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Cover image for Satellite Intelligence Integration in Progress

Satellite Intelligence Integration in Progress 📡 We are currently upgrading the White Waters Sentinel (W2S2) platform to support satellite-enabled monitoring, geospatial intelligence, and early warning capabilities for nationwide security. Right now, our team is working closely with our satellite imagery provider to seamlessly integrate their satellite capabilities into the system, working through the technical API documentation to map out real-time geospatial data ingestion. Looking forward to bringing enhanced operational intelligence and mission-critical response tools to all 36 states and the FCT. Stay tuned for the upgrade!

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Cover image for I build AI chatbots for

I build AI chatbots for websites

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Backend Engineer(2)

Delivering Efficient Fullstack Solutions

Delivering Efficient Fullstack Solutions

Cover image for Express User Manager

Express User Manager

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Cover image for simplicity-js/simplicity

simplicity-js/simplicity

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Cover image for smart-form-validator

smart-form-validator

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Backend Engineer(3)

OBI PASCAL BANJUARE

proAbuja, Nigeria

CTO - blending AI, product, code, and DevOps to build apps.

CTO - blending AI, product, code, and DevOps to build apps.

Cover image for One of the most expensive

One of the most expensive lessons I learned building fintech products wasn't about APIs, infrastructure, or scaling. It was about data types. Years ago, while building a bill payment startup, I discovered we had silently lost over ₦3 million to fractional rounding issues. No hacks. No fraud. Just floating-point arithmetic doing exactly what it was designed to do. The Facts In JavaScript, numbers are stored as floating-point values. That means something as simple as: 0.1 + 0.2 doesn't equal 0.3. It equals: 0.30000000000000004 For a shopping cart, that tiny difference may not matter. For a fintech system processing thousands of transactions daily, those tiny fractions accumulate into real money. What I Initially Did Like many developers, I used decimal currency values directly: It looked clean. But calculations, fee deductions, settlements, and balance updates gradually introduced rounding inconsistencies. Over time, the system started leaking funds through fractions. What Fixed It I switched to storing monetary values in the currency's smallest unit using BigInt. Instead of: Store: Now every operation becomes integer math. No hidden fractions. No rounding surprises. No disappearing money. Pros - Precise calculations - Predictable accounting - Easier reconciliation - Safer ledger systems Cons - Requires conversion when displaying values - Slightly more discipline from developers - BigInt cannot be mixed directly with Number types Do's > Store money in the smallest currency unit (Kobo, Cents, etc.) > Use BigInt or dedicated decimal libraries where appropriate > Convert only at the presentation layer > Build your ledger around integer arithmetic > Never convert BigInt to number on runtime to perform arithmetic operation. Perform the arithmetic operation on the BigInt Type. You can build an api transformer layer to return response in the integer form or leave value in the smallest unit while frontend do the conversion by dividing the value by 100. Don'ts X Store money as floating-point values X Compare currency values using decimal calculations X Round repeatedly during transaction processing X Assume tiny fractions won't matter Fun Fact This is the same principle used by companies like Stripe. Amounts are represented in the smallest currency unit (such as cents) rather than floating-point dollars. Wrap Up In fintech, every fraction belongs to someone. If your system cannot account for every smallest unit of currency, eventually those fractions become real losses. The best time to fix monetary precision is before your first transaction. The second-best time is today.

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Cover image for When you're a FinTech Engineer

When you're a FinTech Engineer and you're excited about AI. A called around 11pm NGT and said: Friend👱‍♂️ : Hey Obi, I've got this client from Canada there want an AI Fitness app Its really an exciting project you should add it to your portfolio. At first I was a bit reluctant, but after a lot of persuasion as someone who enjoys working with me, he keeps talking about the project every single opportunity he has for a good friendly conversation. I finally agreed! 4-months down the line - Find Your Fitness was born! As a Sr. Engineer on the team, one of my core responsibility was to coordinate the project from spring planning, task assignment and follow-ups on ticket to make sure the team were on track with schedule. Jira was my home screen 😂 every morning 😭 . The design team where my friends heading did a great job, but I almost got a heart attack at one time 😂 . It was an exciting adventure indeed, am glad I took my friend up on the offer.

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Cover image for "If money touches your system,

"If money touches your system, a ledger should touch it first." Your backend should be ledger-first by design. If there's even a 0.00001% chance that money, balances, fees, commissions, credits, refunds, rewards, or anything involving an amount will flow through your system, every movement should be recorded in a ledger using double-entry accounting principles. This isn't just for banks, fintechs, or payment processors. Whether you're building: =>A payment rail => An e-commerce platform => A marketplace => A grocery delivery app => A subscription service You need to be able to answer: > Where did this money come from? > Where did it go? > Who owns it right now? > Why did this balance change? > Can we prove it months or years later? A ledger provides an immutable audit trail, complete traceability, and financial correctness. It eliminates balance drift, simplifies reconciliation, and gives your team confidence when investigating disputes or anomalies. You don't need to hold funds to need a ledger. The moment your system represents value, tracks balances, calculates fees, records payouts, or reports financial activity, you're already dealing with accounting. Design for auditability from day one. Retrofitting a ledger later is one of the most expensive engineering decisions you'll make.

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Cover image for I’ve been building SabiFlow for

I’ve been building SabiFlow for a while, and honestly, the most interesting part of the project isn’t the code. It's the problem. Because it's personal. I've experienced that thing where money comes in and somehow, without you really noticing, it starts disappearing. Not because you don’t earn enough. Not necessarily because you're irresponsible either. Sometimes money simply has no job when it arrives. And as an engineer, that got me thinking: What if the problem isn't budgeting? What if the problem is that we’re asking people to make too many good decisions at the exact moment they have the most temptation to make bad ones? That question became the foundation for SabiFlow. Instead of telling someone, "You should save 20% of your income," I started thinking about what would happen if the system simply helped assign every inflow a purpose the moment it arrived. That led me down a rabbit hole. Funnels. Automated distribution. Wallet infrastructure. Virtual accounts. User behaviour. Transaction flows. KYC. Compliance. Even the psychology behind notifications. And this is probably my favourite part of being both an engineer and a founder. I don’t just ask: "How do I build this feature?" I ask: "Why does this problem exist, and what kind of system could make dealing with it easier?" Then the engineer in me comes along and asks: "Okay… but how do we actually make this work reliably?" 😂 That tension between the founder thinking about the problem and the CTO thinking about the system is probably what I enjoy most about building SabiFlow. I’m still figuring a lot of it out. But I'm curious: What’s a problem you’ve experienced personally that eventually made you want to build something around it?

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Backend Engineer(3)

Technical Writer | Documentation Lead | AI Engineer

5.0: Rating

6: Followers

Technical Writer | Documentation Lead | AI Engineer

Cover image for Case Radar

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Cover image for I just published a practical

I just published a practical guide: “How to Choose the Right AI Framework for Your Use Case.” If you're evaluating AI agents (LangChain, CrewAI, no-code tools, etc.), the real question isn’t what’s popular; it’s what fits your business. In this guide, I break down: 1. Team technical capability 2. True cost of ownership 3. Matching tools to real use cases 4. How company size impacts your decision Includes decision flowcharts, cost insights, and a roadmap from prototype to production. Key insight: The winners in AI aren’t chasing hype. They test fast, learn quickly, and scale what works. Read here: Medium: https://shorturl.at/YNyU1 Ready Tensor: https://shorturl.at/X8VgR What’s been your biggest challenge in choosing AI tools?

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Cover image for Understanding Retrieval Augmented Generation

Understanding Retrieval Augmented Generation

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Backend Engineer(1)

oluwole adegboyega

Senior Full-Stack Web & Mobile Application Developer

New to Contra

Senior Full-Stack Web & Mobile Application Developer

Cover image for Bulk Mail Sender Application (App)
[Visual:

Bulk Mail Sender Application (App) [Visual: envelope with outbound batch-send arrows — "Outreach at scale, without the overhead"] The Challenge Small businesses running outbound email campaigns often rely on manual sending or expensive third-party tools, slowing outreach and limiting scale. My Approach I built a bulk mail sender application enabling structured, personalized email batches to be sent efficiently, without dependency on costly external platforms. Focused on clean automation and reliable delivery handling. The Outcome Gave users a faster, more affordable way to run outreach directly.

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Cover image for KETERE online marketplaceThis is an

KETERE online marketplaceThis is an online marketplace app designed and developed by me, a full stack. It's a marketplace for a variety of items.

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Cover image for website design with instant cost estimator embedded in.:

website design with instant cost estimator embedded in.:

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Cover image for website design for a med spa with instant estimator

website design for a med spa with instant estimator

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Backend Engineer(1)

Full Stack Web Developer | n8n & AI Automation Engineer,PHP

$1k+: Earned

1x: Hired

5.0: Rating

92: Followers

Full Stack Web Developer | n8n & AI Automation Engineer,PHP

Cover image for AgriSignal is a digital platform

AgriSignal is a digital platform that helps farmers quickly declare crop treatments and automatically notify nearby residents. It ensures legal compliance, improves transparency, and replaces manual reporting with a fast, map-based system connecting farmers and communities. https://agrisignal.fr (https://agrisignal.fr/)

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Cover image for Scan, import, and search all

Scan, import, and search all your documents right from your phone. No cloud, no subscriptions, no data ever leaving your device. https://docuradar.com

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Cover image for Lately, I’ve been deep in the world of Laravel and Vue.js. C...

Lately, I’ve been deep in the world of Laravel and Vue.js. Crafting web apps that are fast, scalable, and built to last. There’s something really satisfying about turning a rough idea into a clean, functional product that just works. I love collaborating with startups and small teams to bring their vision to life. If you’re building something exciting and need a reliable full-stack dev, I’d love to connect!

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Cover image for Bag Making Haven

Bag Making Haven

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Backend Engineer(6)

proAbuja, Nigeria

Fintech & Payments Engr: Stripe, Paystack & Crypto Checkout

Fintech & Payments Engr: Stripe, Paystack & Crypto Checkout

Cover image for 2Settle — a crypto-to-fiat payment

2Settle — a crypto-to-fiat payment engine I built (Node.js/TypeScript). Users pay in crypto and settle in local currency; it powers spend.2settle.io (https://spend.2settle.io) and chat.2settle, with $583K+ processed YTD. Multi-chain (BTC/ETH/Tron), HD wallets (BIP32/39/44), deposit monitoring, fraud detection, and fiat settlement. API + docs at api.2settle.io.

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Cover image for Drive Boundless Admin Dashboard. An

Drive Boundless Admin Dashboard. An internal staff console for Drive Boundless Auto Solutions, built on the same Sanity dataset as the public site (no separate database). Staff review rental applications, manage the fleet, and handle agreements. Role-based auth (admin via Google SSO, owner via email + password), middleware-protected routes, an application workflow (new, contacted, approved, declined), and automatic rental-agreement PDF regeneration on vehicle changes that never overwrites the original signed agreement. Built in Next.js (App Router, Server Actions) with Sanity, shadcn/Radix UI, and Recharts, and delivered in about a week. Shipped under my Zorex Tech brand. Live at admin.driveboundless.com

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Cover image for Mankind Care: a service website

Mankind Care: a service website for a New Jersey agency (Mankind Care LLC) supporting individuals with developmental disabilities. 10+ service pages including Adult Day Habilitation, Respite Care, Individual & Community-Based Support, Supported Employment, and Behavior Management, plus Home Care, About, and a Contact flow with email via Resend. Built in Next.js, accessible and SEO-optimized with per-service metadata, and delivered in about a week. Shipped under my Zorex Tech brand. Live at mankindcare.net

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Cover image for Prime Supports & Care —

Prime Supports & Care — a service website for a US healthcare provider (Watchung, NJ) supporting individuals with developmental disabilities. 12 service pages, testimonials, careers, and a request-care flow. Built in Next.js, accessible and SEO-optimized. Shipped under my Zorex Tech brand. Live at primesupportsusa.com

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Backend Engineer(1)