Senior Backend Engineer (.NET / PHP) at KissMyButton · Απομακρυσ…

KissMyButton · Greece (Remote/Hybrid)
Location: Remote / Hybrid (Must be currently based and residing in Greece)
Team: International Project (~10 seasoned engineers)

About Us & The Team
We build and maintain high-impact systems where reliability, safe execution, and clean architecture truly matter. You will be joining an established, high-caliber team of around 10 seasoned engineers collaborating on a large-scale international project. We pride ourselves on an engineering culture rooted in low-friction collaboration, pragmatic decision-making, and high autonomy.

About the Role
We are looking for a Senior Backend Engineer to build and maintain the backend behind our core products: APIs, data models, business logic, and integrations. You will own features end-to-end—design, implementation, tests, review, release, and production support—helping shape our technical direction rather than just taking tickets.
Two key factors define this role:

• Navigating Existing Systems: You will work in a large, long-lived codebase where much of your value comes from safely evolving existing systems.
• AI-Assisted Engineering: We expect you to deliver using AI coding tools as a normal part of your workflow, and we assess that skill as seriously as traditional backend practices.

Key Responsibilities

• Design, build, and maintain backend services and RESTful APIs from data model through to endpoint.
• Own features end-to-end: design, implementation, automated testing, code review, deployment, and production support.
• Write clean, testable, documented code, keeping test suites meaningful rather than decorative.
• Optimize relational schemas and queries; track down performance bottlenecks in application code and SQL.
• Review pull requests—AI-assisted ones included—with constructive, specific feedback.
• Mentor mid-level and junior engineers, including guiding safe AI tool usage.

The Part We Weigh Most Heavily: AI-Assisted Engineering

• Daily, productive use of AI assistants (GitHub Copilot, Cursor, Claude Code, ChatGPT, etc.) and the ability to describe your workflow concretely.
• Review Discipline: Applying the same scrutiny to AI outputs as a junior engineer’s PR. You own the diff.
• Context Skills: Knowing how to give models proper code context, constraints, and criteria.
• Knowing the Limits: Clear judgment on when to write code manually for speed, safety, or accuracy.

Required Experience & Skills

• Location: Must currently reside in and be legally authorized to work from Greece.
• 5+ years of experience building and running production backend services.
• Strong backend background in PHP 8.x.
• .NET / C# experience is a major plus (or a strong desire to work with .NET technologies).
• Strong SQL skills and relational data modeling (SQL Server, PostgreSQL, or MySQL).
• Practical experience with REST API design, backward compatibility, and error handling.
• Automated testing habits (PHPUnit, xUnit, or similar) and comfortable using test suites as a safety net.
• Clear written English for asynchronous design notes and pull requests.

Nice to Have

• Framework experience (Laravel, Symfony, or .NET Core) alongside comfort in framework-light codebases.
• Docker, containerized local environments, and cloud exposure (AWS or Azure).
• System modernization experience: updating legacy architectures safely.

How We Work

• Strict Quality Pipeline: Ticket, branch, human review, and green CI pipeline before anything hits production.
• Shared AI Assets: Project instructions, prompts, and workflows live directly in the repository alongside code.

Interview Process
We respect your time and keep our hiring process fast and direct:

• The Core Interview (1.5 Hours): A single, comprehensive session combining an initial intro/culture alignment with a deep technical conversation. We’ll discuss your background, review recent work you’re proud of, dive into architectural concepts, and talk through your day-to-day AI workflow.
• Optional Follow-up (If needed): A short follow-up conversation or practical exercise, conducted only if either side feels a second sync is necessary before finalizing an offer.

How to Apply
Send your CV. Feel free to attach or link anything that shows how you work—a repository, a pull request, an agent workflow, or a write-up of a complex bug you resolved.

Job Type: Full-time

Pay: 1,700.00€ - 2,500.00€ per month

Work Location: Remote