Senior Leader Kotlin Engineer

Nix · Poland; Ukraine · Engineering

Posted 2026-09-29

Apply for this role →

N-iX is looking for a Senior Lead Kotlin Engineer to join our team.

Our customer is a fintech company that provides flexible buy-now-pay-later solutions, enabling consumers to split purchases into transparent, interest-free, or interest-based payments. The customer's Platform team is responsible for managing critical services that are essential to the success and sustainability of the organisation. In simple terms, the team handles transactional communication send-outs to customers via email, SMS, and push notifications. These services demand attention to detail, proactive maintenance, and swift response times to ensure seamless operations. The recent high-priority initiatives include re-architecture/platform modernisation, high availability, and internationalisation efforts; these are vital for our organisation's growth and competitiveness in the market. These initiatives require dedicated expertise and resources to execute efficiently and effectively.

Main Responsibilities:

You will be responsible for owning and delivering quarterly goals for your team, leading engineers on your team through ambiguity to solve open-ended problems, and ensuring that everyone is supported throughout delivery.

You will support your peers and stakeholders in the product development lifecycle by collaborating with product management, design & analytics by participating in ideation, articulating technical constraints, and partnering on decisions that properly consider risks and trade-offs.

You will proactively identify project, process, technology or business issues, advocate for them, and lead in solving them.

You will support the operations and availability of your team’s artifacts by creating and monitoring metrics, escalating when needed, and supporting “keep the lights on” & on-call efforts.

You will foster a culture of quality and ownership on your team by setting or improving code review and design standards for your team, and advocating for them beyond your team through your writing and tech talks.

You will help develop talent on your team by providing feedback and guidance, and leading by example.

On-Call Rotation - There would be an on-call rotation for this role as a requirement.

Role Requirements:

You have 5+ years of experience designing, developing and launching backend systems at scale using Kotlin.

You have a track record of developing highly available distributed systems using technologies like AWS, MySQL/Dynamo and Kubernetes.

You have experience defining a technical plan for the delivery of a significant feature or system component with an elegant, simple and extensible design. You write high quality code that is easily understood and used by others.

You are proficient at making significant changes in a large code base, and have developed a suite of tools and practices that enable you and your team to do so safely. · Your experience demonstrates that you take ownership of your growth, proactively seeking feedback from your team, your manager, and your stakeholders.

You have strong verbal and written communication skills that support effective collaboration with our global engineering team.

This position requires either equivalent practical experience or a Bachelor’s degree in a related field.

Apply for this role →

← Back to all jobs