Hire C# developers

The honest answer is: it depends on the half-life of your C# surface area. If your roadmap leans heavily on high-throughput back-end services in asp.net core and you expect to keep investing in .NET over the next 18-24 months, a specialist will out-deliver a generalist on day-30 throughput and incident response.

If your team is smaller than ten engineers, or C# is one of three or four core technologies, hire a strong generalist who has shipped C# in anger at least twice. The cross-stack pattern recognition will pay for itself the first time you need to integrate ASP.NET Core with another part of the system.

On Haystack we surface both - filtered by whether the candidate self-identifies as a C# specialist and verified against their last two roles. Expect to pay around £70k–£90k for a mid-level UK hire, scaling toward £95k–£135k for senior.

A great C# engineer is not the one with the most stars on GitHub - it is the one who has paged at 3am for a C# service they wrote, and changed how they build because of it. Across the core engineering hires we have placed in 2025-2026, the same patterns keep showing up.

Every stack has its own pattern of plausible-sounding answers that fall apart in production. With C#, these are the patterns that most often correlate with a six-month regret hire on the employer side.

When teams ask us how to evaluate C# engineers beyond a CV, we recommend a 90-minute paid take-home that mirrors real work, not algorithm puzzles. The brief below is one we have refined with employers hiring core engineering teams.

Give the candidate a small, intentionally imperfect C# service that already does high-throughput back-end services in asp.net core. Their task is to add a second capability - unity games and tools - while keeping existing behaviour green. Grade in three parts.

By week one, the new C# engineer should have shipped a small change to production - typically a docs fix, a .NET dependency bump or a minor refactor in high-throughput back-end services in asp.net core. The goal is to validate the development loop, not to ship anything heroic.

By week two, expect them on the on-call rota in a shadow capacity, pair-programming on at least one feature, and asking pointed questions about why specific C# patterns were chosen. If they are not asking those questions, the hire is going to plateau.

By day 30, they should own one cleanly-scoped slice of the C# surface area, have a public ramp-up document, and be the named reviewer on PRs touching that area. Every Haystack employer gets a structured onboarding template - so you are not reinventing the playbook for each hire.