Mobile Engineer

Ciphertext Solutions, Inc. builds secure, scalable financial technology solutions enabling digital innovation for banks, credit unions, and fintech partners. We operate in a SOC 2 and PCI DSS–compliant, cloud‑native environment and specialize in payments, card issuance, and embedded financial services.Our mobile SDKs are a core product, enabling partners to embed secure financial capabilities directly into their own mobile applications.Job SummaryCiphertext Solutions, Inc. is seeking a Senior Mobile Engineer to design, build, and maintain iOS and Android SDKs and applications used by external partners and customers to embed Ciphertext’s capabilities.This role is SDK‑first: you will focus on building stable, well‑designed, well‑documented mobile SDKs that are easy to integrate, version, and operate in a wide variety of partner environments. Mobile applications exist primarily as reference implementations, testing surfaces, and validation tools for the SDKs.You will collaborate closely with Product, UX, and Backend Engineering to shape developer‑friendly APIs while meeting the security, reliability, and compliance expectations of fintech and payments platforms.Key ResponsibilitiesMobile SDK Engineering (Primary Focus)Design, develop, and maintain production‑grade iOS and Android SDKs consumed by external partners.Define clear, intuitive SDK APIs that abstract complex fintech and payment workflows.Own SDK concerns including versioning, backward compatibility, migration paths, and deprecation strategies.Build SDKs that integrate cleanly into partner and third‑party mobile codebases with minimal friction.Support multiple mobile approaches including Kotlin Multiplatform, React Native, and native implementations where appropriate.Reference Apps & Platform Validation (Secondary Focus)Build and maintain internal and partner‑facing reference mobile applications to demonstrate SDK usage.Use apps to validate SDK design decisions, surface integration pain points, and support partner onboarding.Ensure SDK behavior is consistent across platforms and real‑world app environments.Architecture, Quality & Developer ExperienceLead SDK architecture discussions with an emphasis on reusability, testability, and long‑term maintainability.Implement robust automated testing for SDKs (unit, integration, and contract tests).Own mobile build, packaging, and release pipelines for SDK distribution.Produce high‑quality developer documentation, examples, and integration guides.Product, UX & Cross‑Functional CollaborationPartner with Product and UX to translate product requirements into clean SDK interfaces.Collaborate with backend engineers on API contracts, authentication flows, and performance considerations.Provide early feedback on product designs from a partner and developer‑experience perspective.Support partner integrations by diagnosing SDK issues and improving integration ergonomics.Security, Compliance & ReliabilityImplement secure mobile SDK patterns appropriate for fintech and payments use cases.Ensure SDKs meet expectations for encryption, authentication, secure storage, and data handling.Contribute to compliance‑driven development practices aligned with PCI DSS and SOC 2 requirements.Required Qualifications5–7 years of professional experience developing mobile software for iOS and Android.Bachelor’s degree in computer science, software engineering, or related field. Experience working in fintech, payments, banking or another regulated environment. Demonstrated experience building SDKs, libraries, or frameworks used by external teams or partners.Strong proficiency with Kotlin Multiplatform and/or cross‑platform solutions such as React Native.Solid understanding of native mobile development (Swift, Kotlin) and mobile platform constraints.Experience designing APIs intended for long‑term external consumption.Experience collaborating closely with Product and UX teams.Strong communication skills and a high degree of ownership.Preferred QualificationsExperience integrating SDKs into partner or third‑party mobile applications.Familiarity with mobile payment flows, digital wallets, card issuance, or banking integrations.Experience publishing and maintaining SDKs with clear semantic versioning.Knowledge of secure mobile storage, biometric authentication, and device security best practices.Experience supporting external developers or partners during integrations.Familiarity with mobile observability, analytics, and crash reporting tools.Why Join Us?Competitive compensation, including performance incentives and a flexible work environment. Work on cutting-edge fintech solutions, solving real-world banking and payments challenges. Opportunity to work on secure, scalable, cloud-native architectures and modern tech stacks.  Work with a talented, supportive team driven by a shared commitment to excellence. Strong engineering culture focused on code quality, automation, and continuous learning.