Cape Town - Senior Backend C#​/.NET Engineer

• 2–3× per week in the Claremont office 2 positions open Job Code: BE-

Full Time — contract-to-perm considered

Claremont, Cape Town Hybrid

Protium is looking for a Cape Town-base Senior Backend C#/.NET Engineer to help us build and ship production APIs, services, integrations, and backend systems using C#, .NET, SQL Server, and Microsoft/Azure technologies
.

This is a Cape Town–based hybrid role
, with in-person office days typically 2–3× per week at our Claremont office.

As a senior engineer, you will be expected to take ownership of meaningful areas of delivery: understanding requirements, shaping technical approaches, making sensible trade-offs, guiding implementation, supporting other developers, and helping ensure that what we ship is clean, secure, maintainable, and fit for production.

You’ll work on high-quality, API-driven systems where attention to detail matters: clean architecture, maintainability, performance, security, scalability, operational reliability, and long-term supportability.

While this is primarily a backend engineering role
, we value senior developers who understand the full delivery picture. That may include frontend integration requirements, client-facing workflows, mobile/backend interaction, deployment considerations, production support, and the broader technical decisions that affect the success of a system.

Protium is a security-first software development company based in Claremont, South Africa.

We build robust, scalable, future-proof software with a strong emphasis on engineering standards, clean delivery, practical architecture, and long-term maintainability.

Our work is primarily focused on building high-quality software systems for clients in the financial services sector (but not limited to), where reliability, security, correctness, and clear communication matter.

• Cape Town based
• Hybrid
• Office meetups: typically 2–3× per week
• Full-time preferred
• Contract-to-perm considered
• Positions available: 2

This is not a fully remote role. You should be based in Cape Town and able to attend regular in-person office days in Claremont.

You are a strong backend engineer who can take ownership of complex work without needing every detail to be prescribed upfront.

You are comfortable moving between technical design, implementation, debugging, review, and delivery support. You can understand business requirements, ask the right questions, identify risks early, and translate technical direction into working production systems.

You care about good engineering principles, including SOLID, clean architecture, sensible abstractions, design patterns where appropriate, testability, separation of concerns, maintainability, and long-term supportability. You know when to keep things simple, when to introduce structure, and when a technical decision may create future complexity.

You are not just an implementer. You contribute to technical conversations, challenge ideas constructively, mentor other developers, and help raise the quality of the team around you.

You communicate clearly with developers, architects, QA, designers, product stakeholders, and client-facing teams. You are comfortable explaining technical decisions, trade-offs, risks, and delivery progress in a practical, professional way.

You use AI-assisted engineering tools in your day-to-day work as a serious productivity lever, not as “vibe coding”. You use these tools to accelerate delivery, improve feedback loops, explore options, and reduce repetitive work, while still applying strong judgement around design, correctness, readability, testing, maintainability, and security.

• Design, build, and maintain production-grade APIs & Services using C# and .NET.
• Own backend features and technical work streams from planning through to implementation, testing, release, and support.
• Design and implement service layers, business logic, integrations, data access layers, background services, and scheduled processing components.
• Work with SQL Server databases, including schema design, queries, indexes, stored procedures where appropriate, and performance considerations.
• Help shape technical…