Backend Engineer

Upside is a software consultancy built by engineers for engineers. We partner with global companies to solve real complex technical challenges. Were deep into Applied AI and R&D building both production-grade platforms for clients and our own open-source tools like Enthusiast (Agentic AI framework).

We operate in a Forward-Deployed model. We dont sit behind a wall of specs or wait for the tickets. We get into the trenches with the client identify the actual challenges and take full ownership of the solution. Our teams are small (39 people) autonomous and cross-functional.

What it means for you

You wont be assigned to a random project. Youll partner directly with founders and CTOs on technical decisions shaping systems - not just implementing them. Youll have the autonomy to choose the right tools and the ownership to ensure the architecture performs under focus stays where it counts: mission-critical logic and high-impact experiments not repetitive tasks and countless meetings.

We dont do safe or predictable. Youll contribute to strategic open-source projects and build AI-driven solutions.

Role Overview

As a Backend Engineer youll be integral to building and scaling platforms for our global clients. Youll join a high-performing team where your voice matters. Youll design and implement resilient systems while staying close to the code bringing solutions to the table instead of just reporting problems.

Responsibilities

• Technical Execution: Build and maintain scalable backend systems with a focus on clean maintainable code.

• Proactive Problem Solving: Identify issues early and propose actionable ways to fix or optimize them.

• Collaboration: Work closely with the team and stakeholders to translate requirements into working technology.

• Knowledge Sharing: Share your findings and lessons learned from the code to help the team grow.

• AI Implementation: Support the integration of Applied AI features into client products.

• Experience: 2 years of commercial experience in building web applications (Python or Ruby).

• Fundamentals: Solid understanding of OOP clean code and software development lifecycles.

• Databases: Practical knowledge of SQL and relational databases (PostgreSQL).

• Infrastructure: Experience with Git Docker and CI/CD pipelines.

• Mindset: Proactive curious and ready to take ownership of your tasks.

• AI-Native: You use tools like Claude or Cursor to work smarter and faster.

• English: Great command of written and spoken English for team and client communication.

Tech Stack: Python Ruby PostgreSQL AWS Docker Kubernetes.

Value Proposition

• Built for the long run We hire for the company not just a project - looking for passion driven engineers who want to grow with Upside over time

• Small teams real accountability. 3-9 people per engagement. Were small by design. That means your decisions carry weight and you are visible.

• Mission-critical work: We handle complex projects that move the needle for international brands. Our clients are scaling companies established international brands and large institutions. The systems you build will be under real load with real stakes.

• Real Ownership: You take part in the decision making process on technology and empowered to take initiative experiment and drive solutions that create real impact.

• No Micromanagement: We trust you to own your work and deliver outcomes - no unnecessary oversight.

• Collaborative R&D: Contribute to targeted Open-source projects and internal AI research.

• Growth through challenges: Complex problems and direct client exposure means youll grow by action.

• Applied AI as a first-class discipline. We dont bolt AI onto projects as an afterthought. Youll identify where it genuinely moves the needle and lead the implementation - on client work and on our own open-source tooling.

• The tools you want. If something makes you faster or sharper we want you using it.

• Transparent progression path. We have defined engineering levels with clear criteria - youll know exactly what each role looks like and what it takes to get from one to the other. No ambiguity no waiting for someone above you to move on

If you didnt find all the information you were looking for have a look at our handbook - it covers a variety of different matters that could be important at this stage. If theres anything else we did not mention that youre interested in - share your thoughts with us

Salary:

Regular Engineer: 10 000 - 13 600 PLN net VAT

Regular Engineer: 14 800 - 19 300 PLN net VAT

Location:

Office in Kraków hybrid fully-remote.