I'm Md. Akib Ullah Jafor (Akib Jafor), a senior full-stack engineer in Dhaka, Bangladesh. I build complete products end to end: Python and Go services, TypeScript frontends, and the infrastructure that runs them. Six-plus years across FinTech, cloud platforms, AgriTech and retail.
| 💳 Payments & billing Gateways, idempotency, double-entry ledgers, settlement, KYC, subscription billing. |
☁️ Cloud & platform Multi-tenant auth, usage metering, rate limiting, job queues, durable workflows, Kubernetes, OpenStack. |
🧠 AI & ML Evaluated RAG, tool-calling agents with guardrails, MCP servers, LLM gateways, and published ML research. |
- Now: Senior Software Engineer building an OpenStack-based cloud platform for Bangladesh: compute, billing, usage metering and multi-tenant auth.
- Before: payment gateways and billing/settlement for mobile financial services and banks, KYC onboarding for a bank's mobile app, AWD irrigation monitoring for Japanese agricultural consultants.
 |
 |
 |
 |
 |
 |
No install, no sign-up: each opens a running demo in your browser.
E-commerce admin dashboardReact 18, TypeScript, TanStack Query, Recharts on a mocked API. Sign in with admin@shopbd.test / password123.
· code
|
Bilingual RAG with evaluationEnglish/Bangla Q&A with cited answers, retrieval running in the browser, and measured recall@k / MRR. · code |
Tool-calling support agentRefunds, order tracking and escalation with policy guardrails; every tool call visible. 53/53 eval scenarios pass. · code |
Cloud consoleVue 3 + Pinia tenant console: quotas, launch wizard, volumes, security groups, billing. Any email + 6-char password. · code |
More demos: form builder · Bangla i18n playground · log analytics report · Postgres CDC stream, decoded · API references for every backend on its repo's homepage link.
Every repository is a complete project with tests, CI, security scanning, releases and a live demo, API reference or one-click Codespace.
AI engineering · 5 projects
| Repo | What it is |
|---|---|
| rag-eval-lab | Bilingual (English/Bangla) document Q&A with a measured comparison of chunkers and retrievers: recall@k, MRR, nDCG, citation precision. Live demo runs search in the browser. |
| ai-support-agent | Tool-calling support agent that looks up orders and issues refunds within policy, with guardrails, prompt-injection screening and a 53-scenario eval suite. Live demo. |
| llm-gateway | OpenAI-compatible gateway in front of OpenAI, Anthropic and Ollama: fallback, circuit breakers, caching, virtual keys with budgets, cost tracking and streaming. |
| mcp-postgres-analyst | Model Context Protocol server giving AI assistants safe read-only database access: SQL validation, row limits, column masking and an audit log. |
| genai-trace-explorer | OpenTelemetry collector and trace viewer for LLM agents: OTLP/HTTP ingest, GenAI semantic conventions, span trees with critical path, token and cost rollups, per-tool error rates, prompt content dropped at ingest. Live demo. |
Go and Kubernetes · 2 projects
| Repo | What it is |
|---|---|
| go-api-gateway | Reverse-proxy API gateway in Go: JWT/JWKS, rate limiting, health-checked load balancing, circuit breakers, hot reload and Prometheus metrics. |
| k8s-gitops-platform | Helm library chart, Argo CD ApplicationSets and OPA policies deploying three of these services, tested end to end on a kind cluster in CI. |
SaaS building blocks · 5 projects
| Repo | What it is |
|---|---|
| saas-starter-kit | Multi-tenant SaaS starter: FastAPI + Next.js 14, org switcher, team invites, roles, plan entitlements, API keys, billing page. |
| saas-subscription-billing | Recurring billing engine: plans, seats, trials, coupons, exact proration, invoices, dunning and MRR/churn metrics. |
| feature-flags-service | Feature flags with targeting rules, sticky percentage rollouts, segments, SSE streaming and Python/TypeScript SDKs. |
| notification-service | Email, SMS, push and in-app notifications with en/bn templates, preferences, quiet hours, digests and provider fallback. |
| background-jobs-queue | Redis-backed job queue with priorities, cron, retries, dependencies, stalled-job recovery and a React dashboard. |
FinTech and payments · 5 projects
| Repo | What it is |
|---|---|
| fastapi-payment-gateway | Multi-provider payment gateway with a payment state machine, idempotency keys, HMAC-signed webhooks, routing by fee table, settlement and reconciliation. |
| billing-settlement-engine | Django + DRF double-entry ledger, tiered fee schedules, invoicing and partner settlement batches with CSV reconciliation. |
| bkash-python-sdk | Typed sync/async Python client for bKash Tokenized Checkout with retries, token refresh and webhook helpers. |
| webhook-relay | Reliable webhook delivery service: exponential backoff, signatures, circuit breakers, dead-letter queue and replay. |
| kyc-onboarding-api | KYC onboarding workflow with document validation, NID checks, risk scoring, reviewer roles and SLA tracking. |
Cloud platform and backend infrastructure · 10 projects
| Repo | What it is |
|---|---|
| durable-workflow-engine | Durable execution engine: async Python workflows that survive crashes via event-sourced history and deterministic replay, with retries, durable timers, signals and sagas on SQLite or PostgreSQL. |
| pg-cdc-relay | Change data capture for PostgreSQL over native logical replication: its own pgoutput decoder, transactional outbox (table or pg_logical_emit_message), at-least-once delivery to webhooks and Redis Streams, tested end to end on PostgreSQL 14/16/17. Live demo walks through a real captured stream. |
| cloud-usage-metering | Usage ingestion, rating engine with tiered pricing and proration, invoices and budget alerts for cloud resources. |
| multi-tenant-saas-auth | Multi-tenant auth service: rotating refresh tokens, RBAC, org-scoped API keys, invitations and rate limiting. |
| rate-limiter-service | Token bucket, sliding window and GCRA limiters with in-memory and Redis (Lua) backends, plus FastAPI middleware and benchmarks. |
| openstack-resource-manager | CLI to inventory, audit and cost-estimate OpenStack resources, with a fake cloud client for tests. |
| realtime-monitoring-dashboard | FastAPI WebSocket metrics stream with alert rules and a React live dashboard. |
| docker-fastapi-react-template | Production starter: async FastAPI + Alembic + Postgres + Redis, React frontend, nginx, compose for dev and prod, CI and deploy workflow. |
| log-analytics-pipeline | Nginx log parsing, path normalisation, percentiles and anomaly detection into DuckDB, with CLI and HTML reports. |
| url-shortener-analytics | URL shortener with expiry, QR codes, Redis-cached redirects and click analytics. |
E-commerce, retail and bookings · 3 projects
| Repo | What it is |
|---|---|
| ecommerce-api | Django REST e-commerce backend: catalog, carts, stock reservation, coupons, bKash/COD checkout and delivery zones. |
| appointment-booking-system | Doctor appointment booking with timezone-aware slot generation, double-booking protection and reminders. |
| inventory-forecasting | Demand forecasting and reorder-point toolkit for retail POS data with backtesting. |
Frontend engineering · 4 projects
| Repo | What it is |
|---|---|
| react-admin-dashboard | React + TypeScript admin dashboard with TanStack Query, Zustand, Recharts, forms and a mocked API layer. |
| react-form-builder | Drag-and-drop form builder that exports JSON Schema and renders forms with zod validation. |
| vue-cloud-console | Vue 3 + Pinia cloud console UI: instance wizard, volumes, security groups, billing. |
| bangla-i18n-toolkit | Zero-dependency TypeScript library for Bangla numerals, BDT formatting, dates and phone validation. |
AgriTech and reusable libraries · 2 projects
| Repo | What it is |
|---|---|
| agri-field-monitor | AWD irrigation monitoring backend with GraphQL API, field geometry, water-level alerts and progress reports. |
| django-audit-log | Reusable Django app for field-level audit trails with masking, request context and pruning. |
Early Prediction of Postprandial Glycemic Response in Gestational Diabetes Using Continuous Glucose Monitoring and Gradient Boosting Models
Akib Ullah Jafor*, Pronati Das Puja, Shawanti Biswas, Arko Saha, Kamruzzaman Mithu, Khondaker Abdullah-Al-Mamun
Data Modeling, 7(1), 1–7, 2026 · Eman Research · Open access · doi:10.25163/data.7110742
* first and corresponding author · all publications on Google Scholar
Gradient boosting models on continuous glucose monitoring and meal data from 235 pregnant participants predict the 120-minute post-meal glucose response with R² 0.82 (RMSE 0.68 mmol/L). Meal and behavioural context, such as prior meal composition, glycaemic index and meal spacing, outperformed physiology-only baselines.
Deep dives on Engineering Notes: the design decisions, trade-offs and tests behind these projects.
| Article | Project |
|---|---|
| Running webhook workers in parallel without double delivery | webhook-relay |
| Measuring retrieval instead of guessing | rag-eval-lab |
| Guardrails that don't trust the model | ai-support-agent |
| Five rate-limiting algorithms, one Lua script each | rate-limiter-service |
| Refresh-token rotation with reuse detection, and tenancy in one dependency | multi-tenant-saas-auth |
| Idempotency keys done properly in a payment API | fastapi-payment-gateway |
- strawberry-graphql/strawberry · #4752: fix for field arguments named
sourceclashing with permission classes and field extensions (open since 2022 as #2139).
Portfolio · LinkedIn · Google Scholar · GitHub
Open to senior backend / full-stack roles and freelance projects in payments, SaaS platforms and AI-backed products. Private client work, including an offline-first point of sale and a bilingual storefront, can be demoed on request.