Principal Software Developer
colayer
About the role
Overview
- Project Duration: 6-12 months, extension possible
- Commitment: Full-time
Job Description
Our client is looking for a hands-on Principal Software Developer with deep computer science fundamentals and a pragmatic, product-oriented mindset. You combine strong architectural thinking with the ability to ship high-quality code thoughtfully and predictably.
You are fluent in modern engineering practices, comfortable in heterogeneous, service-oriented and distributed environments, and focus on writing robust, maintainable code for systems that scale.
You will help evolve a business-critical platform-leading the transition from a heterogeneous semi-distributed codebase to a strategically aligned, reliable, and scalable architecture. You will balance delivery speed with long-term sustainability and champion tools and techniques that multiply engineering effectiveness.
What you'll do
- Design, build, and run a business-critical software platform using modern frameworks and programming languages
- Spearhead the migration from a semi-distributed codebase to a unified, scalable architecture
- Analyze trade-offs, risks, dependencies, and user value to drive technical decisions
- Solve complex technical problems hands-on, not from the sidelines
- Operate close to production: build it, ship it, support it
- Champion clean code, test coverage, and performance-first thinking
- Evaluate and apply emerging developer tools where they provide real leverage (eg, GitHub Copilot, GPT agents, etc.)
Who we're looking for
- 8 to 12 years of professional experience in software development with at least 80-100% of your last 2-3 years spent coding, shipping, and deploying
- Expert knowledge of C#/.NET Core
- Proven track record of delivering production-grade systems
- Proficient in functional programming and strong static typing (F#, Scala 3, Rust, Haskell, Kotlin, OCaml, etc.)
- Applied architectural knowledge: modular monoliths, microservices, event-driven systems, actors, etc.
- Confident working with relational databases (schema design, migrations, tuning)
- Familiarity with modern delivery stacks: Git, GitOps, CI/CD, Docker, etc.
- Strong communication and collaboration skills; self-starter attitude
- Fluent English (C1/C2); German is a strong plus
Nice to Have
- Experience with Kubernetes and Infrastructure-as-Code tools (eg Terraform, Pulumi)
- Familiarity with AI-assisted engineering tools (Copilot, GPT, linters, analyzers)
- Experience with platform abstraction, developer enablement, or internal tooling
Additional Information
- Web Reference : AJF/931667965-202
- Posted Date : Mon, 18 May 2026
Please note, to apply for this position you will complete an application form on another website provided by or on behalf of colayer. Any external website and application process is not under the control or responsibility of IT JobServe
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