Chibueze Felix

Open to senior Android and backend roles

I build payment systems on both sides of the API.

Chibueze Felix Anyanwu. Senior engineer, seven years across Android and backend. Kotlin, Jetpack Compose and Flutter on the client; Go, Java and Spring Boot on the server. Most of that spent on fintech, EMV payments and POS systems, where both ends have to agree or nobody gets paid.

Hire me Resume
Chibueze Felix Anyanwu
Experience
7+ years
Client
Kotlin, Compose
Server
Go, Spring Boot
Availability
Remote, worldwide

ProfileWho you'd be hiring

Payments are unforgiving. That's the part I like.

A card tap either clears or it doesn't. There's no half-working transaction, no graceful degradation when a terminal loses power mid-authorisation. Most of my career has been spent in that constraint: EMV flows, NFC readers, POS hardware and the fintech apps sitting on top of them.

That work taught me to build for the bad day rather than the demo. Offline queues, retry semantics, tight error states, releases that can be rolled back. I bring the same instinct to the newer things I'm shipping now, including AI features in mobile products and Go services behind them.

I'm most useful to a team that needs a senior mobile engineer who can talk to the payments people, the backend people and the people who actually use the app.

SkillsWhat I work in

Tools, in the order I reach for them.

Mobile

  • Kotlin
  • Jetpack Compose
  • Android SDK
  • Coroutines & Flow
  • Flutter
  • Dart
  • Java
  • React Native

Payments & hardware

  • EMV contact & contactless
  • NFC
  • POS terminal SDKs
  • Card tokenization
  • ISO 8583 messaging
  • Offline transaction queues

Backend & services

  • Go
  • Spring Boot
  • REST
  • gRPC
  • PostgreSQL
  • Firebase
  • Docker

AI in products

  • LLM API integration
  • Prompt & tool design
  • RAG-backed features
  • On-device inference

How I build

  • Clean architecture
  • MVI / MVVM
  • Modularisation
  • Unit & UI testing
  • CI/CD
  • Play Store releases
  • Code review

ProjectsSelected work

Things I've shipped.

Contactless payment terminal app

Android POS application handling EMV contact and contactless flows, receipt printing and offline transaction queuing for merchants on unreliable networks.

Kotlin, EMV, NFC, POS SDKView

Consumer fintech wallet

Wallet and transfer app rebuilt in Jetpack Compose, with a modular architecture that let the team ship independent features without merge pain.

Kotlin, Compose, Spring BootView

Cross-platform merchant companion

Flutter app giving merchants live settlement figures and dispute handling on both Android and iOS from one codebase.

Flutter, Dart, RESTView

AI assistant inside a mobile product

Conversational support layer that answers account questions from the user's own transaction history instead of a generic FAQ.

Kotlin, LLM APIs, GoView

ServicesWays to work together

What you can hand me.

  • Mobile product engineering

    Building or rebuilding an Android or Flutter app end to end, from architecture to store release.

    • Greenfield builds
    • Legacy to Compose migrations
    • Performance and crash cleanup

  • Payments integration

    Getting cards, terminals and processors talking to each other correctly the first time.

    • EMV and NFC flows
    • POS hardware SDKs
    • Offline and retry handling

  • AI features that ship

    Adding LLM-backed capability to an existing product without wrecking latency, cost or trust.

    • Feature scoping and prototypes
    • API and tool integration
    • Evaluation before launch

WritingNotes from the work

Articles.

Mostly things I wish someone had written down before I hit them.

The Fintech Engineer's Toolkit: Free Web Tools That Save You Hours

If you've spent any time building payment systems, you've probably bookmarked paymentcardtools.com. It does Luhn checks, ISO 8583 bitmap decoding, EMV TLV parsing, and a dozen other things you reach for at 2am when a transaction is failing and you can't tell why.

Published May 2026Read

ContactFastest route to me

Tell me what you're building.

Email is best. Say what the role or project is and roughly when you need someone, and I'll come back to you within a day.

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