Krystian Chęciński
Lodz, PL
krystixn.checinski@gmail.com
+48 513988611
krystian-checinski
Cuyer

Android Developer with over three years of experience in designing, building, and improving mobile applications for Android. Skilled in Kotlin, Jetpack Compose, and Kotlin Multiplatform (KMP) with a focus on writing clear, maintainable, and efficient code. Experienced in performance tuning and security, achieving near-zero crash rates and noticeable gains in app speed and stability.

Experience

Mobile Developer
June 2023
 — 
Present
DOZ IT

Focusing on warehouse management solutions, cross-platform architecture, and building mobile applications for pharmacy operations, supporting pharmaceutical workflows.

  • Designed and architected a cross-platform mobile application for high-performance scanning and parsing of 2D barcodes (GS1, QR). Built using Kotlin Multiplatform and reactive streams of data, with a generic, modular approach and hybrid-offline mode.
  • Developed and maintained a warehouse management app utilized in daily operations.
  • Built clean, responsive user interfaces in Jetpack Compose from Figma designs.
  • Architected and launched applications using a multi-module architecture, leading to significant cost savings.
  • Optimized performance to nearly eliminate dropped frames and maintained slow rendering under 10%, even on low-end devices.
  • Achieved a nearly 100% crash-free rate across production releases.
  • Contributed to Kotlin Multiplatform projects.
Junior Android Developer
September 2022
 — 
May 2023
Comarch
  • Implemented search functionality with GraphQL and offline caching to enhance data loading speed and reliability.
  • Integrated Crashlytics and improved app stability by reducing crash frequency.
  • Managed multiple build variants to deliver client-specific app versions.
  • Reduced project build times by approximately 50% by eliminating redundant code, resources, and outdated SQLite databases.
  • Oversaw app releases and updates on the Google Play Store.
  • Refactored and enhanced the user interface, incorporating a dark theme for improved accessibility and user comfort.
Brokerage Coordinator
September 2021
 — 
August 2022
UPS
  • Led process training sessions for team members.
  • Created detailed productivity reports and provided feedback on employee performance.
  • Automated reporting using VBA in Excel, improving efficiency.
Import Brokerage Rater
August 2020
 — 
September 2021
UPS
  • Prepared and audited customs declarations for the Customs Office.
  • Trained new employees on customs compliance and documentation procedures.

Projects

RustHub
June 2025
 — 
Present

Kotlin Multiplatform companion app for Rust players, sharing core logic across Android and iOS.

  • Over 3160 downloads on Google Play Store.
  • Features global server browser, push notifications, and secure authentication.
  • Security: TLS + Certificate Transparency, SQLCipher, Firebase App Check.
Calitracker
April 2022
 — 
Present

Production-grade Android app using Java, various Firebase features, and In-App YouTube player.

  • Achieved over 17,800 downloads and maintained a 4.7 average rating.
RoadReporter
January 2024
 — 
March 2024

Cross-platform app using Compose Multiplatform, sharing UI and logic across Android and iOS.

  • Implemented with MVI architecture.

Education

University of Lodz
October 2023
 — 
June 2025
Master of Engineering in Applied Computer Science
  • Master's thesis: Security of mobile applications on Android
University of Lodz
October 2019
 — 
March 2023
Bachelor of Engineering in Applied Computer Science

    Languages

    Polish:
    Native
    English:
    Professional working proficiency

    Skills

    Core Technologies:
    Kotlin, Java, Android, Jetpack Compose
    Cross-Platform:
    Kotlin Multiplatform, Compose Multiplatform
    Libraries & Frameworks:
    Ktor, Koin, Coroutines, Flow, Hilt, Retrofit, Room, MLKit
    Services:
    Firebase, Google Play Billing, AdMob