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Lead design and development of scalable cross-platform Flutter mobile apps with blockchain integration, ensuring performance, security, and global distribution. | 5-10 years mobile development with 3+ years Flutter expertise, experience releasing apps with millions of users, deep knowledge of iOS/Android platforms, CI/CD, testing, and security. | About the Role: We are seeking a highly skilled Flutter mobile engineer to lead the development of our mobile applications that will reach millions of users globally. You will be responsible for architecting, building, and optimizing cross-platform apps (iOS & Android) that deliver a seamless, secure, and intuitive experience. While blockchain or financial app experience is highly appreciated, the most critical requirement is expertise in delivering worldwide-used, production-grade mobile applications. As a senior technical leader, you will collaborate closely with SDK, backend, product, and design teams to ensure our apps achieve best-in-class performance, reliability, and usability. Key Responsibilities: • Mobile Architecture & Development: • Lead the design and implementation of cross-platform mobile applications using Flutter. Ensure the architecture is scalable, modular, and maintainable. • End-User Experience: • Deliver polished, intuitive, and performant UI/UX across iOS and Android. Collaborate with designers and product managers to translate requirements into world-class user experiences. • Integration with Wallet SDK & Services: • Work closely with the Blockchain Wallet SDK team to integrate blockchain features (transactions, staking, swaps) and backend services into the mobile apps. • Performance & Reliability: • Optimize app startup time, memory usage, network calls, and responsiveness. Ensure resilience across devices, regions, and network conditions. • Release & Distribution: • Own the release process across App Store and Google Play, including CI/CD automation, versioning, and monitoring. Guarantee smooth global rollout and compliance with platform requirements. • Quality & Security: • Drive automated testing (unit, widget, integration, and end-to-end), enforce code quality, and ensure security best practices in mobile development. • Collaboration & Leadership: • Mentor mobile engineers, establish coding standards, and partner with SDK/backend teams to ensure roadmap alignment and timely delivery. Requirements: • Bachelor’s or Master’s degree in Computer Science, Software Engineering, or equivalent experience. • 5–10 years of professional mobile development, with at least 3+ years focused on Flutter (cross-platform) at scale. • Proven track record of building and releasing apps with global user bases (millions of downloads / worldwide adoption). • Deep understanding of iOS and Android ecosystems, including platform differences, store submission processes, and app lifecycle management. • Strong experience with CI/CD pipelines, automated testing, and app distribution. • Knowledge of performance tuning, security best practices, and accessibility standards in mobile apps. • Highly appreciated: Experience in blockchain, fintech, or financial services apps. • Excellent communication skills and ability to collaborate across engineering, design, and product teams.

Lead design and development of a cross-platform Wallet SDK integrating blockchain features, cryptography, and backend services with developer-friendly APIs. | 5-10 years software engineering with 3+ years blockchain SDK or wallet development, strong Kotlin Multiplatform and native mobile skills, multi-chain blockchain experience, and leadership ability. | About the Role: We are looking for an experienced blockchain engineer to lead the design and development of our Wallet SDK, which powers mobile, browser, desktop, and embedded applications. This SDK acts as a high-level wrapper that integrates cryptographic primitives, our MPC SDK, and backend services into a unified developer experience. Your mission is to deliver a full-featured, ready-to-use SDK that enables end-user platforms to interact seamlessly with multiple blockchains — without needing to manage low-level cryptography or protocol quirks. As a senior technical leader, you will architect modular blockchain support within the SDK, ensuring that developers can directly build wallet features such as transfers, staking, swaps, and governance across chains with minimal effort. Key Responsibilities: • SDK Architecture & Development: • Design, implement, and maintain a cross-platform Wallet SDK built on Kotlin Multiplatform (KMP), with seamless integration for native Swift (iOS) and native Android platforms. • Full Blockchain Support: • Implement end-to-end blockchain functionality inside the SDK (transaction construction, broadcasting, staking, governance, DeFi features). Consumers should be able to “just call the SDK” to perform blockchain actions. • Integration of Core Components: • Orchestrate cryptographic primitives, the MPC SDK, and backend services into a single, easy-to-consume package — hiding complexity from end-user apps. • API & Interface Design: • Define clear, developer-friendly APIs that abstract blockchain complexity and provide a consistent interface across mobile, browser, desktop, and embedded platforms. • Performance & Reliability: • Ensure the SDK is lightweight, high-performance, and stable across different environments, with robust error handling and network resilience. • Testing & Documentation: • Build automated test coverage (unit, integration, multi-chain scenarios). Maintain excellent in-code documentation and collaborate with DevRel/product teams to provide developer guides. • Collaboration & Mentorship: • Work with backend, infra, and product engineers to align on roadmap delivery. Mentor junior engineers and guide SDK development best practices. Requirements: • Bachelor’s or Master’s degree in Computer Science, Software Engineering, or equivalent experience. • 5–10 years of professional software engineering, with at least 3+ years in blockchain, SDK, or wallet-related development. • Strong coding skills in Kotlin Multiplatform, plus experience with native Swift (iOS) and native Android. • Proven experience delivering multi-chain SDKs or integrations (EVM, Cosmos, Aptos, Sui, Tezos, Solana, etc.), with support for key wallet features. • Demonstrated ability to design developer-friendly APIs that abstract protocol complexity. • Experience with CI/CD pipelines, SDK packaging/distribution, and versioning. • Strong collaboration skills across engineering, product, and infra teams. • Optional: Open-source contributions in blockchain SDKs/wallets, or prior leadership in multi-chain wallet projects.

Design and implement scalable backend services in Go for a multi-chain wallet ecosystem, ensuring high availability, performance, and clean architecture. | 5-10 years backend development with 3+ years in Go, experience with distributed systems, cross-chain data, databases, caching, messaging, Kubernetes, Terraform, CI/CD, and cloud environments. | About the Role: We are seeking a Senior/Lead Backend Engineer to design and deliver the core services that power our next-generation wallet ecosystem. You will be responsible for building scalable, modular, and high-quality backend systems in Go, supporting features such as transaction history (cross-chain), swap aggregation, and multi-chain balance services. This role requires deep backend expertise, with a focus on code abstraction, clean architecture, and high availability. As a senior technical leader, you’ll partner with SDK, infra, and product teams to create backend services that scale to millions of users while maintaining enterprise-grade reliability. Key Responsibilities: • Service Architecture & Development: • Design and implement backend services in Golang to deliver transaction history, swap aggregation, multi-chain balances, and other wallet-critical features. • Cross-Chain Support: • Build abstractions that unify data and operations across multiple blockchains (EVM, Cosmos, Solana, Aptos, Sui, Tezos, and others). • Code Quality & Abstraction: • Apply best practices in Go software design patterns, dependency management, and modular architectures to ensure clean, reusable, and extensible code. • API Design & Delivery: • Define and deliver robust, developer-friendly APIs consumed by the Wallet SDK, frontends, and external partners. • Performance & Scalability: • Optimize Go services for high throughput and low latency, capable of handling consumer-scale traffic with B2B SaaS-grade reliability. • Reliability & Monitoring: • Implement observability (metrics, logging, tracing, alerting). Guarantee uptime and ensure rapid incident response and recovery. • Collaboration & Leadership: • Work closely with SDK, infra, and product teams to align backend delivery with roadmap goals. Mentor other engineers and establish backend engineering best practices. Requirements: • Bachelor’s or Master’s degree in Computer Science, Engineering, or equivalent experience. • 5–10 years of professional backend development, with 3+ years in Golang. • Proven experience delivering production-grade distributed systems and APIs. • Strong background in cross-chain data integration (transaction history, balance fetching, swaps) is highly valued. • Hands-on experience with databases (SQL/NoSQL), caching, messaging systems, and API gateways. • Familiarity with Kubernetes, Docker, Terraform, and CI/CD pipelines. • Solid knowledge of cloud environments (Google Cloud preferred, AWS/Azure acceptable). • Strong understanding of modular, scalable software architecture. • Excellent problem-solving, debugging, and collaboration skills. • Optional: Previous experience in blockchain, fintech, or other high-scale consumer platforms.