Senior Mobile Developer — B2B Contract | Warsaw | Start Immediately
$5,500—$6,000/month · Full-time · In-office · Relocation Bonus · Milestone Bonuses
On-site role only!
The Opportunity
We're building a modern mobile application that connects to real-world access control and operational systems—secure authentication, biometrics, Bluetooth Low Energy (BLE), payments, and reporting.
We're looking for a hands-on Senior Mobile Developer to own the mobile application, ship features quickly, and work directly with our CEO alongside an experienced .NET backend team.
This starts as a B2B contract with genuine long-term potential to grow into architecture, technical leadership, and team management as the product expands.
This is a senior-level role only. We require someone with a proven history of shipping production mobile applications. Applicants must be able to demonstrate live apps currently available in the App Store or Google Play. Junior and mid-level candidates will not be considered.
What You'll Build
Mobile applications (iOS, Android, or cross-platform) built for production
Work on Authentication, biometrics, push notifications, and BLE functionality
API integrations with our .NET/C# backend team
Customer portal, payments, and reporting integrations
Work directly with the CEO and core engineering team with fast decision-making and minimal bureaucracy
What You Bring
Proven track record: Live mobile applications currently in production with App Store, Google Play, or portfolio links
Strong senior-level commercial mobile development experience
Experience integrating APIs into production mobile applications
Knowledge of authentication, permissions, push notifications, mobile security, and Bluetooth Low Energy (BLE)
Ability to work independently and deliver high-quality software
Based in Warsaw or willing to relocate
Available to start immediately
Nice to Have (Not must)
.NET / C# basic experience
CRM/CMS basic experience (e.g. Umbraco)
Access control or IoT integration experience
Bluetooth Low Energy (BLE) hardware basic experience
Interest in growing into a technical leadership position
What's In It for You
$5,500—$6,000/month (B2B Contract)
Relocation bonus for candidates moving to Warsaw
Milestone bonuses for major product deliveries
Modern office in Warsaw
Direct access to the CEO
Fast-moving environment with minimal bureaucracy
Long-term career growth as the engineering team expands
Applications without proof of shipped production apps will not be considered.
Start immediately.
Interview process takes days, not weeks.
