// Software Developer · aka Monsiu
Full Stack · System Design
I design, build, and ship complete products: backends, web apps, and mobile. My work is live on the web and in six app stores, from Google Play and Amazon to the Microsoft Store, and I sweat the details from clean architecture to store review.
Trusted on Upwork - read client reviews ↗
I'm a software developer who ships complete products, not just code. My flagship is ClauseShift, an AI contract reviewer that cites the exact clause behind every risk it flags. I built it end to end: the Next.js backend, the Flutter apps, billing, the store releases, and the marketing site. The newest is PesaShift, an M-PESA statement analyzer that runs entirely on-device, and before both came Custom RR, an open-source Android hub for custom ROMs that I still maintain and ship across five platforms.
Away from the keyboard I'm a gamer. It clears my head, and I put that focus to good use
running circles around my mates on FIFA EA Sports FC. I also love hackathons for the
same reason I love shipping: a deadline, a hard problem, and something real at the end.
Several projects on this page started exactly that way, and each one taught me a
technology I now use in production.
Frontend
Backend & APIs
Mobile
Data & Cloud
AI & Web3
You can find all my projects on GitHub: github.com/monsiu.
01 //
An AI contract reviewer that shows its receipts: every risk it flags quotes the exact clause it came from, so you verify the wording yourself instead of trusting a black box. Two AI models cross-check every review, a clear risk score and plain-English summary are generated, and key dates and deadlines are pulled out for you. Built as one product across web, Android, iOS, and desktop with self-serve billing (free tier, Pro subscription, and pay-as-you-go credits). Live on Google Play, the web, the Amazon Appstore, the Huawei AppGallery, and the Microsoft Store, with more platforms rolling out. The marketing site speaks seven languages.
Live on Google Play + web + Amazon Appstore + Microsoft Store + Huawei AppGallery · Free tier + Pro · 7 languages · clauseshift.com
02 //
An on-device statement analyser for Kenya's mobile money. PesaShift reads your M-PESA or Airtel Money PDF statement on your phone and shows every fee, every Fuliza charge, and where the money actually went. It walks the statement's balance column to recover charges that are never itemised, arithmetic, not estimates. No SMS permission, no accounts, and the statement never leaves the device. Free to explore recent months; Pro is a one-time unlock, never a subscription, sold through Google Play Billing on Play and M-PESA (Paystack) everywhere else. Live today on the Amazon Appstore, the Huawei AppGallery, Zapstore, and direct APK, with Google Play in review.
v0.1.0 shipped Aug 2026 · Live on the Amazon Appstore · On-device, no SMS permission · Pay once, no subscription · PesaShift site
03 //
The single home for popular Android custom ROMs and custom recoveries. Curates 18 actively maintained ROMs (LineageOS, crDroid, PixelOS, Project Elixir, Project Infinity X, Evolution X, DerpFest, GrapheneOS, CalyxOS, /e/, and more), 5 recoveries (TWRP, OrangeFox, PBRP, SHRP), and 500+ devices, sourced live from the LineageOS wiki and the PixelOS official_devices repo, refreshed nightly by GitHub Actions. Distributed via Google Play, the Amazon Appstore, F-Droid, and GitHub Releases, with a Root section (Magisk, KernelSU, KernelSU Next, APatch, SukiSU Ultra) and native Windows, macOS, and Linux desktop builds alongside Android. Material 3, dynamic color, zero tracking, no Play Services, GPL-3.0.
v1.3.6 released Jul 2026 · 122+ GitHub stars · 18 ROMs · 5 recoveries · 500+ devices · Android · Windows · macOS · Linux · GPL-3.0
04 //
Built a per-request AI API where every query costs $0.001 USDC, settled onchain on Arc blockchain. Deployed a Solidity smart contract that accepts USDC micropayments, built a Node.js API server that verifies payments before returning Gemini AI responses, and demonstrated 57+ live onchain transactions. The project proves sub-cent API monetization is only economically viable on Arc, where gas costs are 100,000x cheaper than Ethereum.
This was part of a hackathon submission for the Arc Blockchain Hackathon which you can view the details
here
You can also demo this system
here
57+ live onchain transactions · Gas costs 100,000x cheaper than Ethereum · Arc Blockchain Hackathon submission
05 //
An autonomous incident-response system that monitors cloud infrastructure in real time, diagnoses issues with a three-agent AI pipeline (Monitor, Diagnosis, Remediation), and executes safe SSH-based fixes on remote servers. Streams live metrics over WebSockets, searches past incidents with a ChromaDB vector store, and auto-generates PDF post-mortems. Handles CPU surges, memory pressure, disk I/O, DDoS, and DB bottlenecks with a whitelisted command set, no arbitrary shell input.
Built for the AMD Developer Hackathon 2025 under Track 1: AI Agents & Agentic Workflows. You can demo this system here.
AMD Developer Hackathon 2025 submission · 3-agent autonomous pipeline · Real SSH remediation with whitelisted commands
// want something like these?
Websites from $500, web apps from $1,500, mobile apps from $3,000. Fixed quotes, store submission included, reply within 24-48 hours.
A selection of my credentials. Tap any card to view the certificate as a PDF, in the browser.
Monsiu Tech - ClauseShift
Building and running ClauseShift, an AI contract reviewer, as a solo founder. I own the whole stack: the Next.js backend and AI pipeline, the Flutter apps, self-serve billing, store submissions across five app stores, the release automation, and the marketing site in seven languages. Live on Google Play, the web, the Amazon Appstore, the Huawei AppGallery, and the Microsoft Store.
Kenya Revenue Authority - KRA
Supported business-critical applications at Kenya's national tax authority: triaged and resolved technical issues, kept core systems running, and worked alongside IT mentors in a large, high-stakes environment.
Upwork
Delivered IT support and software consulting projects for clients on Upwork, earning verified positive reviews and repeat business.
Self Employed
Built websites and applications for local businesses and personal projects, sharpening the fundamentals I still rely on: clean code, clear communication, and shipping on time.
01 //
Need a website or full-stack web app? I build fast, accessible, modern sites and dashboards. From landing pages to e-commerce and custom SaaS, with hosting, auth, payments, and APIs handled end to end.
02 //
Cross-platform Android and iOS apps built with Flutter and Firebase. From idea to published app, including auth, push notifications, payments, and ongoing support.
Want proof? I'm a verified freelancer on Upwork - check my client reviews ↗
Open to new roles, freelance projects, and interesting problems. Project inquiries get a plan and a fixed quote within 24-48 hours.
Thanks for reaching out. I will get back to you at the email you provided, usually within 1 to 2 business days.