Available for work · Warsaw / Radom & remote

Peter
Senior Android Developer

8 years building native Android apps — Kotlin, Jetpack Compose, clean architecture.

8
years of experience
15+
apps shipped
8
companies & clients
PL · EN
working languages
About

I build Android products

I've been building Android apps since 2018 — that's 8 years of shipping products from first sketch to Google Play release. I've taken more than a dozen apps through the full lifecycle, both in teams and solo.

I care about clean code, deliberate architecture and performance, without losing sight of the UX details that decide whether an app is a pleasure to use. I reach for new tools in the Android ecosystem when they genuinely raise the bar — not for novelty's sake.

I make fluent use of AI in my daily work — Claude (Claude Code) and ChatGPT — from generating and refactoring code to building my own skills and agents that automate my workflow. I treat AI as a real engineering tool, not a gimmick.

Peter Mikolajewicz
Stack

Technologies I use

Native Android end-to-end — from architecture to release.

Language & Core

  • Kotlin
  • Java 7/8
  • Coroutines / Flow

UI & Design

  • Jetpack Compose
  • Android SDK
  • Navigation Component
  • Material
  • Figma

Architecture

  • MVVM
  • MVI
  • MVC
  • Clean Architecture
  • Hilt / Dagger 2
  • Koin

Data & API

  • Room / SQLite
  • DataStore
  • REST / JSON
  • Firebase

DevOps

  • CI/CD
  • GitHub Actions
  • Play Console
  • Git
  • Agile / Jira

Testing & Quality

  • Unit tests
  • Mockk
  • Google Truth
  • Code review

AI & Workflow

  • Claude Code
  • ChatGPT
  • AI-assisted development
  • Custom skills & agents
  • Prompt engineering
Portfolio

Apps

Selected projects. The list keeps growing.

Path

Experience

2022 – Present

Senior Android Developer & Tech Lead

Freelance / contract

I deliver Android projects for clients across industries — some as Tech Lead: leading the team, code reviews, mentoring junior developers. I design the architecture (Clean Architecture, MVVM, MVI, SOLID) and own quality, performance and UX. Kotlin, Jetpack Compose, Coroutines/Flow, Hilt, CI/CD. Most engagements are covered by a non-disclosure agreement (NDA) — I can't disclose details or client names.

Jul 2021 – Jul 2022

Android Developer

BlueSoft

Built and maintained Android apps for a retail chain — including the app for Żabka's autonomous self-checkout store. Kotlin, MVVM, Coroutines/Flow, LiveData, Hilt + Koin, DataStore, Clean Architecture, MQTT, Navigation Component.

Google Play ↗
Jan 2021 – Jul 2021

Android Developer

One Way

Worked on and developed an Android app for a cooperative society. Kotlin, MVVM, Coroutines/Flow, Hilt, Room, REST.

Google Play ↗
Aug 2020 – Jun 2021

Android Developer

Carebits

Led the design and development of a medical CTG app for doctors and nurses to interpret cardiotocography (CTG) readings — a domain demanding precision and reliability. Kotlin, MVVM, Coroutines/Flow, Hilt, DataStore.

Google Play ↗
Feb 2018 – Jul 2020

Android Developer

TaxusIT

Where my Android journey began. I designed and implemented key features across a range of apps for the Polish State Forests, working with product managers and stakeholders. Java, Kotlin, MVC/MVVM, SQL, Firebase, REST.

Contact

Let's talk about your project

Open to B2B collaboration, remote.

hello@petermikolajewicz.dev