Senior Fullstack Engineer (Angular + C#/ .NET)

Home Vacancies Senior Fullstack Engineer (Angular + C#/ .NET)

*instinctools is a software development company that provides custom software solutions for businesses of all sizes. Our team works closely with clients to understand their specific needs and provide personalized solutions that meet their business requirements.

Our team is looking for a Senior Fullstack Engineer (Angular + C#/ .NET) for one of our clients.

The client is a fintech startup providing cutting-edge software-as-a-service solutions to institutional investors. Their current offering includes advanced financial analysis, trade flow, and portfolio management solutions.

About the role: This role will be primarily responsible for designing, developing, and maintaining backend services, APIs, and data pipelines, while collaborating closely with frontend engineers to support performant, reliable user experiences. The ideal candidate brings strong system design instincts, experience working with data-intensive applications, and the ability to translate sophisticated financial and operational requirements into secure, scalable, and high-performance solutions.

Our expectations of the candidate:

Experience in C#/.NET (ASP.NET Core)
Experience in Angular
Expertise in SOLID principles and commonly used design patterns
Working knowledge of relational databases
Attention to good UI/UX design
Good communication skills
Ability to work in agile-based project management structure
Familiarity with Git.

Tasks:

Design, build, and maintain backend services, APIs, and core application logic that power user‑facing applications.
Develop and enhance frontend features using modern JavaScript frameworks, ensuring seamless integration with backend systems.
Own and evolve system architecture with an emphasis on scalability, security, reliability, and performance across both backend and frontend components.
Collaborate closely with product managers, frontend engineers, backend engineers, and cross‑functional teams to translate business requirements into end‑to‑end technical solutions.
Build and maintain data pipelines, integrations, and communication layers between internal and external systems.
Implement and review automated unit, integration, and end‑to‑end tests across backend and frontend codebases to ensure quality and stability.
Troubleshoot and resolve production issues across the stack, optimize performance, and proactively identify potential technical risks.
Participate in architectural design discussions, code reviews, and contribute to maintaining high‑quality technical documentation.
Support the full lifecycle of feature delivery – from initial design to implementation, deployment, and post‑release monitoring.

Soft skills:

Self-starter who is passionate about technology
Keen eye for automation and improving efficiency
Ability to provide leadership and accountability for work they undertake
Takes ownership of their work and has exceptional attention to detail
Has excellent communication skills and the ability to articulate their thoughts and ideas
Comfortable with fast-paced and strongly collaborative environments
Able to take on ideas and feedback from both technical experts and business thought-leaders.

English: Upper-Intermediate

We offer:

flexible working time (overlap with New York time is important)
professional and ambitious team
transparent system of professional and career development
a pleasant financial motivation depending on goals
learning opportunities, seminars and conferences and time for exploring new technologies
the opportunity to realize your potential outside the projects: we arrange meetups and conferences where our staff can perform, develop professional communities
full remote work
partial compensation of medical insurance (Luxmed) and multisport card
co-funding for language courses (Polish and English)

Join us and be part of a team that is changing the world through technology.

Important Notice Regarding Your Personal Data Security

At *instinctools, we take the security of your personal data very seriously. Please be informed that all official communication, offers, and correspondence from *instinctools are conducted only through our verified company resources, including:

Official Email Domain: @instinctools.com
Company Website: https://www.instinctools.com

Important Reminder:
*instinctools will NEVER ask for sensitive personal or financial information, including:
– Bank account details
– Credit/debit card numbers
– Passwords or PINs

If you receive any suspicious requests claiming to be from *instinctools via unofficial channels (e.g., personal emails, social media DMs, or phone calls), please:

– Do not respond or share any information.

– Report it immediately to compliance@instinctools.com or your official contact.

Your trust and security are our top priorities. For any questions, always verify through our official channels.

Thank you for your attention and cooperation.

Developers

*instinctools is a developer of IT solutions for Western Europe. We have over 350 projects in our portfolio. The spheres are different – from healthcare and medicine, training and education, to digital advertising, economics and IT. For the software implementation and maintenance across such a number of projects, competent developers are important.

We use a modern technology stack, the key of which are:

Javascript, ReactJS, Angular, Node.js, Golang, Python, Java, iOS, Android, Blockchain, AWS.

Join the *instinctools team!

*instinctools Poland
We have had a representative office in Poland (Warsaw) since 2021. Our Polish team consists of highly qualified and experienced specialists – most of them are Middle to Senior level Developers.
Right now we’re on the lookout for bright and innovative minds to join our professional team!