.NET Performance Engineer- Global tech. company - UK - remote
Excellent opportunity to join a new team, owning the runtime health and throughput characteristics of the platform. This is a specialist contributor role — you won't be building feature logic, you'll be ensuring the systems that run it do so efficiently, reliably, and at scale.
Skills/experience
* AI development experience - usage of AI tools (Claude, CoPilot, ChatGPT)
* 4-5+ years of .NET / C# development with a demonstrable specialism in performance engineering
* Deep, hands-on experience with .NET profiling tools — dotMemory, dotTrace, PerfView, Visual Studio Diagnostic Tools, or equivalent
* Strong understanding of .NET memory management internals — GC generations, LOH, pinned objects, finalisation, and how allocation patterns affect runtime behaviour
* Experience optimising high-throughput data processing pipelines — including async/await patterns, Channel, pipelines, and avoiding synchronisation bottlenecks
* Proven ability to diagnose large dataset query performance issues across both relational (SQL) and document databases, including index analysis and query plan interpretation
* Familiarity with ETW, EventPipe, and diagnostics tooling (dotnet-trace, dotnet-counters, dotnet-dump)
Duties:
* Profile, diagnose, and resolve performance bottlenecks across .NET services — from GC pressure and memory leaks to thread contention and I/O saturation
* Own memory management strategy across long-running services — heap allocation patterns, LOH fragmentation, finaliser queues, and GC tuning (gen0/1/2, server vs. workstation, DATAS)
* Investigate and optimise high-throughput data pipelines — batch processing, streaming patterns, buffer management, and backpressure handling
* Identify and resolve large dataset query performance issues — index utilisation, query plan analysis, pagination strategies, and aggregation efficiency across both relational and document databases
* Establish and maintain performance benchmarking infrastructure using BenchmarkDotNet and load testing tooling — define baselines, track regressions, and gate releases on performance criteria
* Conduct performance-focused code reviews — identify allocations, boxing, closure captures, LINQ misuse, and other common .NET performance anti-patterns
* Collaborate with product engineers to surface performance constraints early in design, without blocking feature delivery
* Produce clear diagnostics and findings documentation that non-specialists can act on
Excellent company, team and opportunities, apply now!!