Sr. Flutter Engineer

About Telna

Telna is a global connectivity company that provides eSIM, IoT and mobile network technology to travel brands, mobile network operators and enterprises. Our engineering team builds consumer apps and platforms that let millions of people get connected in seconds, wherever they are in the world.

About the Role

You will be a senior technical owner of our Flutter mobile platform, which powers consumer travel eSIM apps and white-labeled apps for mobile network operators. Flutter is our primary stack for iOS and Android. We use native Android (Kotlin) and, where needed, iOS (Swift) for what the platform demands, such as eSIM provisioning, device integrity and OEM-specific behavior.

This is a hands-on role with significant architectural influence. You will shape how we structure, scale and release multiple branded apps from a shared codebase, set engineering standards for the mobile team, and mentor engineers across experience levels. You will work directly with product, design, backend and QA, and you will often be in the room when customer needs are translated into technical solutions.

What You'll Do

• Own the architecture of our Flutter apps: modular package structure, state management, dependency injection, navigation, and a clear boundary between shared and brand-specific code.
• Build and evolve a multi-tenant, white-label app framework so one codebase can ship many branded apps, with per-brand themes, configuration, feature flags, flavors and independent release pipelines.
• Deliver high-quality features across the full eSIM journey: plan discovery, checkout, installation, activation, top-up and usage management.
• Write and maintain native Kotlin (and Swift where needed) modules exposed to Flutter via platform channels, Pigeon or custom plugins, especially for eSIM/eUICC provisioning and device-level capabilities.
• Integrate region-specific payment methods, including card processors, mobile money, local gateways and wallets, and build secure, resilient checkout flows with strong failure and retry handling.
• Define API contracts with backend teams, and design analytics and event schemas so transaction and behavioral data reconcile cleanly across systems.
• Build in-app support, ratings and feedback, and eSIM status experiences that reduce support load and improve retention.
• Contribute to client-side fraud and abuse prevention, including device integrity checks, secure token handling and anti-tampering measures.
• Drive performance, stability and release quality: profiling, crash monitoring, staged rollouts, store compliance and CI/CD automation.
• Lead code reviews, write technical design documents, raise the bar on testing practices, and mentor junior and mid-level engineers.
• Evaluate and introduce tools, packages and patterns, and make pragmatic build-vs-buy decisions.

What You'll Bring

Required

• 6-7 years of professional mobile development, with 4+ years of production Flutter and multiple apps shipped to both the Play Store and App Store.
• Deep command of Dart and Flutter internals, including the widget lifecycle, rendering, isolates and performance profiling.
• Proven experience architecting large Flutter codebases using state management such as Riverpod or Bloc, with clean modular architecture and monorepo or multi-package setups (for example Melos).
• Strong working proficiency in native Android (Kotlin), including Coroutines/Flow, Gradle and the Android lifecycle, enough to build and maintain platform channels and native plugins independently.
• Experience integrating REST/GraphQL APIs, handling auth flows (OAuth/JWT) and building offline-tolerant apps.
• Hands-on experience integrating payment SDKs or gateways, with an understanding of PCI-conscious flows.
• Solid grasp of mobile security: secure storage, certificate pinning, Play Integrity and App Attest.
• Strong testing discipline across unit, widget, integration and golden tests.
• Experience owning CI/CD and release pipelines (Fastlane, Codemagic, GitHub Actions or similar).
• Proven ability to mentor engineers, lead technical decisions and communicate with product and business stakeholders.

Strongly Preferred

• Experience with eSIM, SIM or telecom-related APIs (EuiccManager, carrier privileges, LPA integrations, Core Telephony).
• Experience building white-label or multi-brand apps using Flutter flavors, modular packages or configuration-driven UI.
• Experience writing and publishing custom Flutter plugins, or using FFI for platform-specific integrations.
• Working knowledge of iOS native (Swift) and Apple's eSIM capabilities.
• Experience with mobile analytics, attribution and event schema design.
• Experience with push notifications, deep linking and in-app messaging.
• Familiarity with fraud, risk or device-signal tooling in consumer apps.
• Prior experience in travel, fintech, telecom or connectivity products.
• Open-source contributions or technical writing in the Flutter ecosystem.