Senior Android Developer / Engineer
Open To Work
Cristiano Winter
1VALET
Gatineau,Quebec
Work Preference
Job Search Status:
Open to work
Desired Job Title
Senior Android EngineerSenior Android DeveloperSenior Mobile EngineerAndroid Tech LeadStaff Android Engineer
Work Type
Full TimeContract Work
Location Preference
Remote
Minimum Desired Compensation
$60000/yr
Important To Me
Work from home optionFlexible work hours
2
Languages
1
Certification
13
Years of experience
Senior Android Developer with 13 years in software and 9+ in mobile, specializing in connected devices and secure credentials: Wear OS, NFC digital keys, and Bluetooth Low Energy (BLE) smart-lock integration, built in Kotlin and Jetpack Compose.
At 1VALET I own Android end to end for a smart-building access platform with 45K+ daily active users across 200+ buildings, holding a 99.9% crash-free rate. I built its Wear OS companion app alone from scratch and led the move to a multi-module Clean Architecture across 5+ engineers. Before that, at Ambev Tech, I led a mobile team and built architecture and CI/CD for applications running on 1M+ retail points of sale across Brazil.
Fully remote · Eastern Time (UTC-5/UTC-4), aligned with Latin America and US hours · Available as an international contractor · English (professional working proficiency) and Portuguese (native).
Core skills: Kotlin · Jetpack Compose · Android SDK · Wear OS · NFC · Bluetooth Low Energy (BLE) · Clean Architecture · MVVM · Coroutines · Flow · Koin · Dagger · Room · Retrofit · Offline-first Room/SQLite · Firebase Crashlytics · LeakCanary · CI/CD · Azure DevOps · Flutter · Kotlin Multiplatform
Work History
Senior Android Developer
4 Years 9 Months- Own Android end to end (architecture, quality, releases) for consumer apps with 45K+ daily active users across 200+ buildings, holding a 99.9% crash-free rate while collaborating across time zones.
- Built and shipped the Wear OS companion app alone, from scratch: secure door unlock, NFC digital keys, watch-to-phone sync, and its own CI/CD release pipeline.
- Engineered anti-tampering and screen-capture protection across 100% of credential and digital-key flows, meeting enterprise compliance for live residential buildings.
- Integrated Bluetooth Low Energy (BLE) digital keys with Nuki smart locks and strengthened biometric session handling.
- Eliminated session failures under high load by introducing single-flight request deduplication.
- Implemented offline functionality backed by Room/SQLite local persistence.
- Profile and optimize performance and memory with Android Profiler and LeakCanary; track production stability with Firebase Crashlytics and Analytics.
- Led the migration to multi-module Gradle and Clean Architecture (MVVM) across 5+ engineers, cutting incremental build times from ~13 to 8 minutes and isolating tests by module.
- Leading the migration of legacy XML screens to Jetpack Compose (about 20% converted so far).
- Shipped two product lines from discovery to production: an Events & Meetings platform and an in-app commerce marketplace.
- Tech: Kotlin, Jetpack Compose, Coroutines, Flow, Koin, Retrofit, Room, Wear OS, NFC, BLE, Stripe, Twilio, SignalR, Firebase (Crashlytics, Analytics), Azure DevOps, JUnit, MockK, Android Profiler, LeakCanary.
Mobile Engineer
1 Year 7 Months- Contributed to architectural design and implementation of new Android projects for one of the largest beverage companies in the world, with apps serving a retail distribution network of 1M+ points of sale across Brazil.
- Managed a mobile development squad of 4+ engineers, conducting weekly code reviews and technical guidance sessions that reduced average PR cycle time and improved overall code quality.
- Developed 3+ Proof of Concepts (POCs) evaluating new frameworks and libraries, directly informing architecture decisions adopted across multiple production projects.
- Technologies: Kotlin, MVVM, Coroutines, Koin, Room, LiveData, Retrofit, Flow, Navigation Component, Multi-module Gradle, Wiremock, Mockito.
Mobile Tech Lead
6 Months- Designed and implemented Flutter application architecture from scratch, establishing patterns adopted by the full mobile team across 2+ simultaneous projects.
- Built CI/CD pipelines on Azure DevOps and Azure Pipelines for Flutter, cutting release cycle time from days to hours by automating build and deployment in the absence of official Flutter support on App Center.
- Led technical decision-making and sprint refinements for a cross-functional mobile team, improving delivery predictability and reducing scope creep across quarterly roadmap items.
- Technologies: Flutter, Dart, Mobx, Dio, MVVM, Flutter Modular, HiveDB.
Mobile Developer
1 Year 11 Months- Designed and implemented mobile application architecture for Android and iOS across multiple client projects simultaneously, enabling dual-platform delivery from a single codebase.
- Automated CI/CD pipeline using Azure DevOps and App Center, reducing .apk and .ipa delivery from hours of manual effort to fully automated minutes after each pull request merge.
- Managed Play Store and Apple App Store release cycles for multiple applications, maintaining a 100% submission success rate with zero rejected builds over a 2-year period.
- Configured push notification infrastructure for multiple mobile applications, improving user re-engagement across client deployments.
- Technologies: Kotlin, Java, Swift, Android, iOS, Azure DevOps, App Center.
Mobile Engineer
6 Months- Developed new features and maintained existing cross-platform mobile applications serving field agents across Android and iOS using a shared Xamarin Forms codebase.
- Implemented Bluetooth thermal printer communication by integrating a native C++ library via PCL into Xamarin Forms, enabling field agents to issue and print fines directly from mobile devices — eliminating paper-based workflows.
- Delivered shared C# business logic across Android and iOS targets using Xamarin's PCL, achieving 80%+ code reuse between platforms and reducing duplicate maintenance effort.
- Technologies: C#, Xamarin Forms, MVVM.
Software Engineer
7 Months- Developed an automated system update delivery flow using WebSockets, enabling the host server to push software updates to all local network client machines without manual IT intervention.
- Eliminated manual update overhead entirely for local network deployments, reducing technician time spent on routine software distribution from hours per cycle to zero.
- Built and maintained internal desktop tooling using C# and Windows Forms to support daily business operations.
- Technologies: C#, SQL, Windows Forms.
Software Engineer
3 Years 1 Month- Developed and maintained enterprise software platforms over a 3-year tenure, contributing to multiple product releases across several business-critical modules used by clients in the logistics sector.
- Implemented new features in C# and SQL Server across Windows Forms desktop applications, directly reducing manual business process steps for end users.
- Maintained and optimized SQL database queries and stored procedures supporting core business workflows, improving data retrieval performance for daily operational use.
- Provided direct client support, diagnosing and resolving technical issues to maintain high client satisfaction and platform uptime.
- Technologies: C#, SQL, Windows Forms.
Education
Bachelor of Technology - Information Technology
Skills
Mobile Platforms: Android
iOS
Wear OS
Languages: Kotlin
Java
Dart
Swift
C#
SQL
Frameworks & UI: Jetpack Compose
Flutter
Xamarin
Android Views (XML)
Architecture: Clean Architecture
MVVM
MVP
MVC
Multi-module Gradle
Async & Reactive: Coroutines
Flow
RxJava
LiveData
Dependency Injection: Koin
Dagger 2
Networking: Retrofit
OkHttp
Dio
Alamofire
Local Storage: Room
SQLite
HiveDB
MMKV
CoreStore
Testing: JUnit
MockK
Mockito
Wiremock
Turbine
Espresso
AI / ML: On-device LLMs
MediaPipe
Gemma
ML Kit
Integrations: Firebase
Twilio
Stripe
SignalR
NFC
BLE
Tools & CI/CD: Git
Azure DevOps
App Center
Azure Pipelines
Gradle
UI and UX design skills
Object-oriented programming
Android development
Unit testing experience
Performance & Monitoring: Android Profiler
LeakCanary
Firebase Crashlytics
Firebase Analytics
memory management
debugging
Also: Kotlin Multiplatform
Navigation Component
WebSockets
offline-first persistence
Nuki BLE smart locks
Google Play releases
Practices: Agile/Scrum
code review
mentoring
CI/CD
cross-time-zone collaboration
LANGUAGES
English: Professional Working Proficiency
Portuguese: Native
Certification
- Android Multithreading Masterclass
- Online Course
- 2022
- Software Architect
- 2018
- Xamarin Development for Android and iOS
- 2017
- Introduction to ASP.NET Core
- 2019
Timeline
Senior Android Developer
1VALET
01.2022 - CurrentRead More
Mobile Engineer
Ambev Tech
06.2020 - 01.2022Read More
Mobile Tech Lead
Ambev Tech
12.2019 - 06.2020Read More
Mobile Developer
Ellevo Soluções
01.2018 - 12.2019Read More
Mobile Engineer
AMcom Sistemas de Informacao
07.2017 - 01.2018Read More
Software Engineer
Hiper
11.2016 - 06.2017Read More
Software Engineer
Sensum Sistemas
10.2013 - 11.2016Read More
Universidade do Vale do Itajai
Bachelor of Technology from Information Technology
Read More