Mobile Engineer (m/w/d) – Flutter, Enterprise-App

SaltRock

6d • Hybrid

About The Position

Develop and further enhance SecureID, SaltRock’s Flutter mobile app for iOS and Android. SecureID is a PKI and credential wallet that turns smartphones into hardware-backed digital identities. Private key material is stored in Secure Enclave or Android Keystore and never leaves the hardware. The app supports NFC door access, email signing, push-based two-factor authentication, and passwordless sign-in, while organizations manage users, cards, and integrations through SecureID Workspaces.

The mobile app uses Flutter/Dart, Riverpod, and GoRouter, with native Swift and Kotlin bridges for hardware-backed keys and device capabilities. It also integrates with platform key stores to provide certificates to third-party applications, and supports NFC/HCE, BLE, and biometrics. The app is designed as a thin client: business logic resides in the backend, while the app handles user experience, secure key storage, and device functions. Builds and releases use Codemagic, including signing and publication to the Apple App Store and Google Play.

You will implement new UX designs and enterprise features, coordinate interfaces with the backend, and help publish app releases. SaltRock uses AI tools such as Claude Code and Codex in development; you are expected to understand, critically review, and take responsibility for code you merge, whether written by you or generated. The role offers flexible, mobile work, with home-office options and offices in Münster and Cologne.

Requirements

• Professional experience with Flutter/Dart in apps published in app stores.
• Experience with apps connected to a SaaS backend, including login, tenants, and push notifications.
• Routine use of AI development tools, with a commitment to understanding, reviewing, and taking responsibility for generated code.
• Willingness to learn new technologies.
• Written and spoken German and English.

Nice To Haves

• Swift or Kotlin experience.
• Experience with app-store processes, signing, and Codemagic.
• Experience with NFC/HCE, BLE, biometrics, Secure Enclave, or Android Keystore.
• Knowledge of Riverpod and GoRouter.
• Foundational knowledge of PKI and X.509.

Responsibilities

• Develop and maintain the SecureID app for iOS and Android using Flutter.
• Implement the new UX design in the app and support releases to the Apple App Store and Google Play.
• Build enterprise features, including organization switching and push notifications.
• Work on biometrics, NFC, BLE, and secure key storage with experienced colleagues.
• Coordinate interfaces with the backend to keep the app lean.
• Implement tickets using Claude Code or Codex and personally review the results.
• Understand, critically assess, and take responsibility for all code merged, including AI-generated code.

Benefits

• Latest MacBooks or Windows Surfaces, also available for private use.
• Company credit card with expense-management tool.
• Edenred City card with €50 per month.
• 30 days of vacation.
• Trust-based working hours.
• Home-office option and modern offices in Münster and Cologne.
• Professional certifications, leadership and soft-skill training, and access to LinkedIn Learning and Udemy.
• Flexible, mobile, and location-independent work.

What This Job Offers

• Job Type: Full-time
• Education Level: No Education Listed