where I've built

Where I've worked

Briton Otieno smiling in a blue sweater in front of a wooden wall
  • Core contributor to TaskBridge, an enterprise project and data platform that replaces JIRA for staff and clients.
  • Led the move of data from JIRA to TaskBridge: issues, workflows, roles, history and dependencies, with no lost records.
  • Built backend features and tuned database queries to keep it fast under heavy use.
  • Fixed production problems with nginx, Passenger and ActionCable, and helped bring the system back after a full-disk outage.
  • Built the Fixed Income Terminal in Ruby on Rails: bond pricing, yield to maturity, coupon schedules, cash flows, duration and settlement amounts.
  • Built the Money Market Fund Terminal: interest accrual, NAV and fund performance.
  • Moved data from old workflows to the new WallStreet.Africa website, and built pipelines and reporting for market research.
  • Delivered full-stack apps in Ruby on Rails and PostgreSQL, with role-based access, caching, background jobs and live updates.
  • Integrated payment and fintech APIs.
  • Set up CI/CD that cut defects after release by more than 40%.

clarity for African markets, one right number at a time

my toolbox

What I bring to a team

Payments and Markets

  • M-Pesa Daraja (STK Push, callbacks)
  • PayPal
  • Africa's Talking
  • Payment reconciliation
  • Webhooks and signed links
  • NSE, CBK and KNBS pipelines
  • Bond pricing, YTM, duration
  • MMF NAV and accrual
  • NASI and NSE 20

Back End

  • Ruby on Rails
  • Python
  • Node.js and Express
  • Nest.js
  • .NET
  • PHP (Laravel)
  • REST and GraphQL
  • WebSockets
  • Sidekiq

Front End

  • React and Redux
  • Next.js
  • TypeScript
  • JavaScript
  • HTML and CSS
  • Charts and dashboards
  • Accessibility

Data, Cloud and Security

  • PostgreSQL
  • MySQL
  • Redis
  • Docker and Linux
  • AWS (EC2, S3)
  • Cloudflare Workers and D1
  • GitHub Actions CI/CD
  • RSpec, Jest and TDD
  • OAuth2 and JWT
  • Audit logs and rate limits