Justin
Kiplangat

Invoicing SaaS for freelancers and SMBs — create invoices, set up recurring billing, accept Paystack payments (card, bank transfer, mobile money), and generate PDFs via an async BullMQ worker. Built as a Next.js + Express monorepo.

Multi-tenant B2B CRM handling the full sales lifecycle — pipeline management, bulk email/SMS campaigns, support ticketing, geolocation, and a granular permissions system. Built on Next.js server components with a strict service-layer API over PostgreSQL.

In daily use at TechriseGlow Limited

Full loan lifecycle platform for Kenyan SACCOs and microfinance institutions — member onboarding, KYC, application, approval, disbursement, repayments, and arrears. Dual-role routing between loan officers and members under a single application.

Replaces paper-based workflows at active SACCOs

ML-powered credit scoring tool that replaces gut-feel lending decisions with an auditable, explainable model. Returns a default probability, a 300–850 score, a risk tier, and SHAP-driven explanations that tell loan officers exactly which factors drove the decision.

86.4% accuracy · 93.0% ROC-AUC

Production POS system for retail chains and restaurants — tackled hard offline-sync bugs, debugged race conditions in concurrent checkout flows, and reviewed PRs across a Vue 3 + Electron + Docker stack. Built barcode-first in-memory lookup, M-Pesa push payments, and a warm-cache strategy that eliminated transaction latency under flaky internet.

Live across multiple retail branches · end-to-end tested