Nairobi, Kenya · Est. 2025
Most developers use AI as an autocomplete sidekick. Mortise runs Claude Code as a coordinated engineering team instead. A planner, coder, tester, and reviewer each work to a written plan, with fixed boundaries around payments, auth, and data. You get production software you own, built by one accountable person.
01 / Selected Work
Built on Bubble
No longer live
A multi-platform social-media management SaaS: OAuth per network, queue-backed publishing, and proper observability. Built on Bubble to ship a real multi-tenant product quickly, in a case where speed mattered more than owning exportable code.
Built on Bubble
No longer live
An AI compatibility engine with a multi-compare design that scores many candidates in a single Claude API call. Built on Bubble for fast delivery.
Concept demo
Catalog and quote-request platform for a Kenyan medical equipment supplier. Built around a request-for-quote flow instead of a cart, the pattern most B2B procurement sites get wrong. Next.js + Supabase, solo build with Claude Code. Concept demo, not a client engagement.
Concept demo
A speculative demo for a Kenyan architecture and construction studio, addressing the market's trust gap. Clients get a password-gated portal with real milestone-based progress on their build, plus an inquiry system for new requests.
02 / Method: the subagent orchestrator
A single AI session left to run on its own produces plausible code with quiet mistakes buried in it. Mortise splits the work across four roles instead. Each has one job and checks the one before it, so speed does not come at the cost of correctness.
The part that matters most is the boundaries. Anything touching money, identity, or data access stays off-limits to an agent without an explicit, recorded decision, and every milestone leaves a record you can read back later.
Turns the brief into a written plan, milestone by milestone, with explicit “done = X” criteria and named boundaries on sensitive paths, all before any code is written.
Implements one milestone at a time in small, reviewable commits. It never touches a protected path such as payments, auth, or data without a recorded decision.
Exercises each milestone end to end, covering types, build, and the real user flow, then reports what actually happened. Failures get reported, not smoothed over.
Reads the diff critically, checking whether anything touches money, identity, or data access the plan did not authorize. It signs off milestone by milestone and leaves that record behind.
03 / What Mortise Builds
Marketing sites and web apps that are fast, accessible, and yours to own. Built to hold up in production past the first hundred users, not just to look good in a demo.
Multi-tenant products, including the parts that are hard to get right: role-aware auth, database-enforced access, payments, and the automation that connects them.
Claude-powered features and agentic workflows for real tasks: structured extraction, multi-step orchestration, and internal operations tools. Every line gets reviewed rather than trusted on faith.
Bubble.io MVPs when they fit, recommended only when speed to a first version matters more than owning exportable code. If you will need to own and scale the codebase, I will say so and build it in code.
04 / About
Mortise is the studio practice of Derick Mutuma, based in Nairobi. Two years spent building products that clients run their business on, not prototypes that stall after a demo.
Claude Code is the core method, applied with the discipline a payment system demands: a written plan before any code, sensitive paths handled deliberately, and every milestone documented well enough to review. The goal is not raw speed. It is software you own and can hand to any other developer.
Every build gets the same fences and review pattern as a payment system, whether or not this one touches money.
Each milestone ships with a testable “done = X,” not a status update.
If a metric isn’t real yet, the site says so instead of guessing.
The one who scopes the build is the one who ships it. No hand-off, no telephone.
05 / Contact
“Derick is a highly professional and disciplined developer. He takes detailed notes, asks the right questions, and provides clear daily end of day updates with Loom videos, ensuring full transparency. He genuinely cares about the project and thinks about structure and scalability.”
A paid, focused 30 minutes to work through what you are building and whether I am the right person to build it.
Book a discovery callOr email hello@mortisetech.solutions
