Senior C Developer

As a Senior C Developer at Endava, you will be a hands-on engineer on a large-scale datacenter migration, moving a long-lived payments platform from UNIX/AIX to Linux (RedHat) with applications refactored for the cloud (AWS). You will own the analysis, refactoring, and consolidation of C applications, relying on strong systems fundamentals to reason about behaviour and deliver with autonomy. Beyond the migration, you will have the opportunity to grow into long-term BAU, project, and client-integration work on the same platform. Responsibilities: - Designs, estimates, and implements technical solutions for medium/high complexity applications. - Participates actively in all phases of application development lifecycle. - Collaborates with various project stakeholders to provide support for clarifying requirements, processes, architecture, and priorities. - Recommends and promotes IT industry standards, tools, practices (DevOps, etc.) to achieve well-engineered software products. - Proposes improvements and escalates risks/issues related to development activities. - Participates in the review of the work done by development team members. - Learns and applies new technologies, practices, and tools as appropriate to the project. - Shares experience and knowledge gained from projects. - Has responsibility for the work of others and for allocating resources. - Influences the team, customers, and suppliers. - Makes decisions which influence the success of projects and team objectives. - Can propose and design solutions autonomously. - Can articulate solutions to technical and non-technical stakeholders. Required: - 5+ years of hands-on software development experience, with strong, demonstrable expertise in plain C. - Strong UNIX experience across AIX and Linux (RedHat), with proven ability to port and refactor applications from AIX to Linux RedHat. - Shell scripting (Korn/ksh, Bash) for build, run, and deployment tasks across UNIX environments. - Solid command of the C build and debug toolchain — Make/Makefiles, gcc, gdb, and core-dump analysis. - Experience refactoring and consolidating applications, including redesign work as part of a migration. - A self-directed developer mindset, comfortable delivering with autonomy and taking ownership end to end. - Good communication skills, able to articulate solutions to technical and non-technical stakeholders. Nice to have: - SQL and relational databases (DB2, Oracle), including embedded SQL (Pro*C / ESQL/C) as used in C applications. - Sockets, TCP/IP, and inter-process communication (IPC) for application integrations and messaging. - Cross-platform porting   awareness — endianness, data-type sizes, and compiler differences between AIX (POWER) and Linux (x86). - Payments / financial transaction processing domain knowledge (e.g. ISO 8583, card and transaction switching, PCI DSS). - Git/GitHub — the project is migrating source control from SCCS to…