Jobs Kotlin

Our Mission and Vision

At Solidgate, our mission is clear: to empower outstanding entrepreneurs to build exceptional internet companies. We exist to fuel the builders — the ones shaping the digital economy — with the financial infrastructure they deserve. To achieve that, we're on a bold path: to become the #1 payments orchestration platform in the world.

We believe the future of payments is shaped by people who think big, take ownership, and bring curiosity and drive to everything they do. That's exactly the kind of teammates we want on board.

Solidgate is part of Endeavor — a global community of the world's most impactful entrepreneurs. We're proud to be the first payment orchestrator from Europe to join — and to share our expertise within a network of outstanding global companies.

About the Team and Role

You'll join the Core team — the team responsible for the services that sit at the heart of Solidgate's payment processing. Core services define what a payment is, integrate with numerous internal services for correct routing, run antifraud checks, and process payments through providers, covering card payments as well as Apple Pay and Google Pay. This is the critical path for every payment on the platform, so the team's work directly defines the reliability and speed of the whole system.

The team is actively growing new functionality, supporting existing services, working down technical debt, and maintaining an SLO of 99.99%+ across all of its services. The stack is built around high-load, low-latency requirements: a microservices architecture with Kotlin as the primary language, Protobuf RPC over Buf/Connect, PostgreSQL as the main database, and Kafka for asynchronous processing, with fully automated production deployments and an advanced monitoring and observability setup. Infrastructure is continuously improved by a dedicated platform team, with IaC ensuring transparent, reproducible, and scalable management.

Your team — Product Manager, Tech Lead (Backend), three Backend Software Engineers (Senior), one Frontend Software Engineer (Middle), AQA Engineer, and System Analyst.

What you'll own

Your focus will be on:

• taking part in product decisions across the full development lifecycle
• designing and developing backend functionality for our products
• collaborating with other teams to build reliable solutions for payment processing
• improving the performance, scalability, quality, and reliability of our systems

You'll grow from feature-level tasks toward owning a dedicated service or domain, taking part in the team's design and technical decisions.

You're a great fit if you have

• 4+ years of experience with Java/Kotlin
• 5+ years of experience with SQL (PostgreSQL)
• Experience designing reliable, scalable systems
• Experience with distributed systems
• Experience with cloud environments (AWS/GCP)
• 2+ years of active hands-on use of AI tools

Nice to have

• Fintech experience and experience with high-load, complex systems
• Observability/Alerting tools (Prometheus, Grafana)
• Infrastructure as Code (Terraform)
• Event-driven systems (SQS / Kafka)

Why Solidgate?

High-impact role. You'll work at the very core of our payment processing — the critical path for every transaction, including Apple Pay, Google Pay, and card payments.

Great product. We've built a fintech powerhouse that scales fast. Solidgate isn't just an orchestration player — it's the financial infrastructure for modern Internet businesses. From subscriptions to chargeback management, fraud prevention, and indirect tax — we've got it covered. We hold financial licenses in key regions and are a direct Visa & Mastercard partner and sub-reseller (top 5 globally).

Massive growth opportunity. Solidgate is scaling rapidly — this role will be a career-defining move.

Top-tier tech team. Work alongside our driving force — a proven, results-driven engineering team that delivers.

Modern engineering culture. TBDs, code reviews, solid testing practices, metrics, alerts, and fully automated CI/CD.

💌 The Extras: 30+ days off, unlimited sick leave, free office meals, health coverage, and Apple gear to keep you productive. Courses, conferences, sports and wellness benefits — all designed for ideas, focus, and fun.

Tomorrow's fintech needs your mindset. Come build it with us.

🫂 Know top talent? We're always on the lookout. Refer someone for our role, and if they get hired, there's a bonus waiting for you — simple as that.

We're looking for a strong Senior Full-Stack Developer to join an enterprise project for one of our long-term clients. We already have several developers successfully working on this project.

📌 Project

A web-based platform for German leasing companies that supports and automates their core business processes.

🚀 Senior Full-Stack Developer (Kotlin / Java / React)

📍 EU only (business trip to Germany for 3–4 days every 6 months)

🗣 English: C1

✅ Requirements

6+ years of software development experience

Strong Kotlin & Java

Strong React

Experience with PostgreSQL and/or MongoDB

CI/CD & automated testing

Experience with AI-assisted development

Strong software engineering and problem-solving skills

⭐ Nice to have

Node.js

💼 Responsibilities

Develop and enhance full-stack applications

Build scalable backend services with Kotlin & Java

Develop modern React features

Improve architecture and optimize existing modules

Collaborate with Product, QA, and DevOps teams

Participate in code reviews

We are looking for an experienced Senior Mobile Developer to become a key member of our product team and help shape the future of our mobile platform.

About the Product:

The project is under NDA.

It is a professional GPS navigation and route planning platform designed for enterprise customers. The solution provides advanced mapping, routing, navigation and geospatial capabilities for business-critical operations. It integrates with leading mapping providers and serves international customers across logistics, transportation, public services, emergency response and other industries where reliable navigation is essential. (LinkedIn)

The first milestone is to modernize the existing iOS application and successfully release it to the App Store. After that, you will play a leading role in building a shared Kotlin Multiplatform codebase for both iOS and Android.

Responsibilities:

• Maintain and improve the existing iOS application.
• Prepare and publish production releases to the App Store.
• Participate in architecture and technical decision-making.
• Develop a shared Kotlin Multiplatform codebase.
• Collaborate with an international product team.
   

Requirements:

Must Have;

• 5+ years of commercial mobile development experience.
• Strong expertise in Swift and iOS SDK.
• Hands-on experience publishing applications to the Apple App Store.
• Experience with App Store Connect, Apple Developer Console and TestFlight.
• Solid understanding of modern mobile architectures (MVVM, Clean Architecture, etc.).
• Commercial experience with Kotlin.
• Experience with or strong interest in Kotlin Multiplatform.
• Upper-Intermediate (B2) English or higher.
   

Nice to Have:

• Kotlin Multiplatform (KMP/KMM).
• Android development experience.
• Jetpack Compose.
• German language skills.
• Experience with mapping, navigation or GPS products.

• Startup or product company background.

   

We Offer:

• Long-term collaboration.
• Fully remote position (Ukraine).
• Opportunity to influence product architecture.
• Work on an international software product.

• Small, highly efficient team with fast decision-making.

   

When applying, please include:

• Links to App Store applications you've worked on.
• A brief description of your role in the release process.
• Your Kotlin / Kotlin Multiplatform experience.
• Your English proficiency level.
• Whether you speak German.

We're looking for a Senior Kotlin Backend Developer to join an international team building scalable backend solutions. You'll take ownership of features from design to production, contribute to architectural decisions, mentor teammates, and communicate directly with the client in English.
 

Requirements

• 5+ years of backend development experience
• Strong commercial experience with Kotlin
• Solid understanding of JVM fundamentals (concurrency, memory management, garbage collection)
• Experience with Spring Boot (or Ktor / Micronaut)
• Strong knowledge of REST API design
• Experience with relational and/or NoSQL databases (PostgreSQL, MySQL, MongoDB, etc.)
• Hands-on experience with ORM frameworks such as JPA, Hibernate, or Exposed
• Experience writing unit and integration tests using JUnit and MockK
• Good understanding of Clean Architecture, SOLID principles, Git, CI/CD, and code review practices
• Experience with AI-assisted development tools such as GitHub Copilot, Cursor, Claude, or similar
• Upper-Intermediate or higher English (direct communication with clients)
   

Responsibilities

• Design, develop, and maintain backend services using Kotlin
• Own features end-to-end, from technical discussions to production deployment
• Build clean, maintainable, and well-tested code
• Participate in architecture and system design decisions
• Review code and mentor other engineers
• Collaborate directly with clients and cross-functional teams
• Continuously improve development processes and engineering quality
   

Nice to Have

• Experience with microservices architecture
• Docker and Kubernetes
• Cloud platforms (AWS, GCP, or Azure)
• Messaging systems (Kafka, RabbitMQ)
• Redis or other caching technologies