Principal Software Engineer (POS Developer)

Job Title: Principal Software Engineer (POS Developer)Department: DevelopmentLocation: NASTP, Karachi OfficeJob Type: Full time (on-site)Reports To: Team LeadLead the architecture, development, and evolution of enterprise-level Android POS applications, payment engines, and device integrations. Own high‑risk transactional components such as ISO‑8583 communication, EMV workflows, and secure channel management. Mentor teams, define platform-wide standards, and ensure exceptional reliability, performance, and compliance across all POS software layers.Key ResponsibilitiesArchitecture & Platform LeadershipDefine POS system architecture across Android, ISO‑8583 engines, device layers, security, and modular components.Own technical decision-making for performance, scalability, and long-term maintainability.Establish and govern engineering standards, design patterns, and code quality expectations.Advanced Android & Kotlin DevelopmentLead Kotlin/Java development using Android SDK, Jetpack, WorkManager, threading, and profiling.Oversee mission‑critical payment and offline/online flows.Compose UI ArchitectureArchitect large-scale Compose UI systems following Material 3, unidirectional data flow, and state hoisting.Optimize rendering, reduce recompositions, enforce UI performance guidelines.ISO‑8583 & Transaction Engine OwnershipOwn host communication layers including pack/unpack, MAC generation, DE mapping.Lead all sale/void/reversal/settlement flows and ensure compliance with acquirer test suites.Device & Hardware IntegrationsArchitect EMV, NFC, MSR, and printer integrations with abstraction layers.Handle OEM SDK limitations, battery/thermal constraints, and failover strategies.API & Ecosystem IntegrationsLead integrations for gateway, loyalty, discount, routing, onboarding, and merchant systems.Define standards for Retrofit/Http/Ktor usage, caching, retries, and contract management.Security & PCI DSS ComplianceOversee PCI compliance, encryption models, secure key storage, obfuscation, secure input, and TLS.Approve all sensitive cryptographic and security-critical implementations.Observability & Stability EngineeringDefine logging and metrics strategy; integrate crash analytics and monitoring tools.Lead high-severity incident response, RCA, and preventive actions.Leadership & MentorshipMentor senior engineers; lead design sessions and architecture reviews.Coach teams on ISO‑8583, EMV, Compose, architecture patterns, and performance engineering.Documentation & GovernanceMaintain ADRs, API specs, architecture diagrams, test matrices, and compliance documents.RequirementsEducation:Bachelor’s in Computer Science or related field (Master’s preferred).Experience:8+ years in Android/Kotlin engineering, with at least 5+ years in POS/Payments.Proven leadership in building scalable POS platforms and payment engines.Skills:Advanced Kotlin, Jetpack Compose, Coroutines, Hilt, WorkManager.Deep understanding of ISO‑8583, EMV, NFC, socket/TLS communication.Strong architecture mindset: clean architecture, multi‑module, MVI/MVVM.Hardware SDKs: EMV kernels, printers, scanners.API development expertise (Retrofit/OkHttp/Ktor).Strong Git practices, CI/CD pipelines, branching strategies.Excellent troubleshooting, profiling, and performance optimization skills.Nice to Have:Backend exposure; SQL Server/EF Core understanding.Observability stack experience (ELK, Prometheus, Firebase).Experience with containerization and cloud deploymentBenefitsHealth InsuranceLife InsuranceProfessional Development OpportunitiesEqual Opportunity StatementWe are an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, or disability.