Kotlin/Java Developer (Merchant Response)

Our team is developing a payment gateway for accepting funds from users on behalf of merchants, as well as sending funds from merchants to users. The system involves storing user payment data and is subject to PCI DSS compliance. It contains multiple integrations with payment systems, providers, and other gateways and processors, including 3DS.

Job Responsibilities

• Developing new payment features and services;

• Processing and resolving requests from technical support and users as part of daily duties;

• Designing and implementing APIs (external and internal);

• Creating and maintaining processes in Camunda;

• Participating in the design and development of high-load system architectures;

• Supporting and enhancing existing solutions and services;

• Writing high-quality, test-covered code (unit tests, integration tests);

• Conducting code reviews;

• Optimizing system performance and database queries;

• Analyzing and resolving production incidents and bugs;

• Analyzing documentation from external providers, conducting quick checks, and defining epics and tasks based on Proof of Concept;

• Collaborating with the QA team to ensure the high quality of the delivered product;

• Maintaining technical documentation and writing technical specifications;

• Assisting in onboarding new developers and ensuring code quality;

• Definition and formation of technical epics — analyzing existing solutions, identifying opportunities to improve system architecture, performance, and reliability, preparing improvement proposals, and aligning them with the team lead and architect;

• Participation in the creation of business epics — analyzing requirements, assessing feasibility, and proposing alternative or optimized solutions based on technical expertise; collaborating with analysts and product managers to determine the best implementation approach;

• Preparing tasks based on approved epics, ensuring proper detailing and alignment with architectural and business requirements;

• Estimating task completion timelines, participating in sprint planning, and providing accurate technical time and effort estimates.

Important and Challenging Tasks:

• Creating and developing reliable payment solutions with high security and performance levels;

• Processing and resolving requests from technical support and users as part of daily duties;

• Optimizing the performance and scalability of payment systems;

• Integrating complex external providers;

• Participating in ensuring system compliance with high-security requirements (PCI DSS and others).