Md Sabbir Ahmed Khan · Available worldwide

Senior Software & Systems Engineer. Android & Mobile Tech Lead.

Mobile, real-time & connected systems — with Android as my deepest specialization.

I’m Sabbir — “Rey” to most people. For 12+ years I’ve shipped software where the app is one part of a larger system: aircraft control with live video and TCP telemetry, Samsung Health syncing wearables over BLE, fintech payments across two markets, and offline-first tools for factory floors with barely any network.

I build AI-first: coding agents write the first draft, and twelve years of engineering judgment decides what ships. With Kotlin Multiplatform and agentic AI in the loop, that reaches past Android — iOS, backend and web, from one pair of hands.

Explore my work Download CV

01 · Pathways

What brings you here?

For recruiters & eng leaders

Hire me

12+ years of senior engineering, deepest in Android — Kotlin, Compose, KMM — plus the systems around the app: real-time telemetry, video pipelines, BLE, offline-first sync. Led the ground-up rewrite of a mission-critical real-time platform. Open to senior, staff and lead roles worldwide.

See the work

For clients

Build your product

You bring the idea. I design, architect and ship it: Android and iOS from one Kotlin Multiplatform codebase, with agentic AI extending the same hands to the backend and web around it — and 12 years of engineering discipline behind every decision.

How I work

For founders

Partner with me

No technical co-founder? I become your CTO under contract: I build the entire product now, and earn a percentage plus equity when you raise. Your job is the raise — mine is everything technical.

Read the model

02 · How I build

AI-first, engineer-led.

Coding agents write faster than any human. Judgment still decides what ships — and I own every line.

Agents

Claude Code
Codex
Gemini CLI
Cursor

Connected to

Jira
Figma
GitHub
Firebase

Decide

Architecture, tech stack, module boundaries, interfaces. The decisions that make or break a codebase are made by me, before any code is generated.

Delegate

Coding agents — Claude Code, Codex, Gemini — implement to spec, connected through MCP to the real tools: Jira tickets, Figma designs, GitHub, Firebase.

Review

Line-by-line. I track what the agents used, correct wrong turns, and re-architect where needed. AI accelerates; it doesn’t get a vote.

Ship

Tests, CI/CD, store release, production monitoring. The same delivery discipline I’ve applied for 12 years — just reached a lot faster.

One codebase, both platforms

Kotlin Multiplatform puts the business logic, networking and data layer in one place and ships it to Android and iOS — with Compose Multiplatform sharing the UI where sharing it is the right call. I have shipped iOS features too, so I know where the shared line should fall.

One engineer, the whole product

Agentic AI extends my reach past mobile: backend, web, infrastructure and release automation, directed by someone who has shipped production systems for twelve years. For a founder or a small team that means an all-in-one software solution, not an app plus four more contractors.

AI velocity, engineering discipline →

12 +

years shipping Android

100 +

apps delivered as founder of Power GP BD

500 K+

downloads on a single app (Theatre)

100 +

developers trained across Asia, selected by Google

03 · Selected work

Projects that shipped.

All projects →

Case study

Let’s build something that ships.

A role, a product, or a partnership — the first step is the same.

Get in touch rey.sabbir@gmail.com