Ruby on Rails Developer

SOFTSWISS; Województwo mazowieckie; On-site; PLN 180,000 - 280,000; Full time

Benefits offered by this job

Private health insurance

Sports benefits

Free English lessons (online)

Local language courses

Paid time off

Maternity leave support

Referral program rewards

Upskilling, internal workshops

Job summary

SOFTSWISS continues to expand its team and is looking for a Senior Ruby on Rails Developer. We need a skilled, proactive and accomplished professional who shares our culture and values and is ready to contribute to the development of cutting-edge gaming solutions.

SOFTSWISS is building high-load gaming infrastructure and AI-enabled features that power millions of players. You will own architecture, ensure performance, reliability, and production readiness while collaborating with

Qualifications

• 4+ years of commercial Ruby on Rails experience.
• Strong SQL and PostgreSQL skills with large tables.
• Experience with distributed systems and background jobs (Sidekiq).
• Hands-on with AI coding tools in daily work and critical testing.
• You can spot hallucinated APIs in code reviews.
• Experience designing REST and/or gRPC APIs; OpenAPI familiarity.
• Proficient with Git, CI/CD, Docker; comfortable with Kubernetes.
• Experience with observability tools (Prometheus, Grafana, Sentry).
• English and Russian at upper-intermediate level or higher.

Responsibilities

• Design, build and evolve Ruby on Rails services powering the iGaming platform.
• Work in an AI-augmented workflow using coding assistants for scaffolding and review.
• Integrate LLM-based features to deliver real value like fraud signals and automation.
• Own performance, profile hot paths, tune PostgreSQL queries, and design caching strategies.
• Review code (human and AI) and mentor engineers to set AI usage standards.
• Participate in architecture discussions and cross-team initiatives.

Skills

Ruby on Rails

SQL & PostgreSQL

Distributed systems

AI tooling literacy

Code review

REST/ gRPC APIs

Git & CI/CD

Observability tools

English & Russian

Tools

Git

Docker

Kubernetes

CI/CD

Prometheus/Grafana

Sentry

Job description

SOFTSWISS continues to expand its team and is looking for a Senior Ruby on Rails Developer. We need a skilled, proactive and accomplished professional who shares our culture and values and is ready to contribute to the development of cutting-edge gaming solutions.

About Product:

Full-service modular software platform to manage online casino operations

Purpose of the role:

We're looking for an engineer who treats AI as a force multiplier rather than a shortcut: someone who ships fast with modern tooling, but still owns the architecture, the edge cases and the production behaviour of everything they deliver. If you share our culture and values and want to build high-load gaming solutions used by millions of players, we'd love to talk.

Key responsibilities:

• You'll do design, build and evolve Ruby on Rails services that power our iGaming platform: high-throughput APIs, payment and wallet flows, real-time game integrations and back-office tooling.
• Work in an AI-augmented workflow: use coding assistants and agents (Cursor, Claude Code, GitHub Copilot or similar) for scaffolding, refactoring, test generation and code review and take full responsibility for the quality of what gets merged.
• Integrate LLM-based features into the product where they create real value: [fraud and risk signals, player-support automation, content generation, internal analytics copilots].
• Own performance and reliability: profile hot paths, tune PostgreSQL queries, design caching and background-processing strategies, and drive incidents to root cause.
• Review code (human- and AI-written alike), mentor mid-level engineers and help set the team's standards for how we use AI responsibly and effectively.
• Take part in architecture discussions, technical planning and cross-team initiatives.

Required Experience:

• 4+ years of commercial Ruby on Rails experience; deep understanding of Ruby internals, Rails conventions and where to break them.
• Strong SQL and PostgreSQL skills: indexing, query planning, migrations on large tables without downtime.
• Solid grasp of distributed-system fundamentals: message queues, idempotency, eventual consistency, background jobs (Sidekiq or similar), caching (Redis).
• Hands-on experience with AI coding tools in day-to-day work, and a clear opinion on when they help and when they hurt.
• You can spot a plausible-looking hallucinated API in review.
• Ability to evaluate and verify AI-generated code: you write and read tests critically, understand what the code actually does, and never merge what you can't explain.
• Experience designing and consuming REST and/or gRPC APIs; familiarity with OpenAPI.
• Confident with Git, CI/CD pipelines, Docker; comfortable reading Kubernetes manifests and logs.
• Experience with observability tooling (Prometheus/Grafana, Sentry, OpenTelemetry or similar).
• Upper-Intermediate or higher English and Russian level

Nice to have:

• Experience integrating LLM APIs (OpenAI, Anthropic, open-weight models) into production Ruby applications - prompt design, structured outputs, evaluation, cost and latency control.
• Familiarity with RAG pipelines, vector databases (pgvector, Qdrant) or agent frameworks.
• Understanding of security and data-privacy implications of AI features (PII handling, prompt injection, model output validation).
• Experience in fintech, payments or iGaming; knowledge of regulatory and responsible-gaming requirements.
• Contributions to open-source Ruby projects, talks or technical writing.
• Working knowledge of Go, Elixir or TypeScript for cross-service work.

Our stack:

AI tooling: [Cursor / Claude Code / Copilot] with team-wide guidelines on usage, review and security.

LLM integrations via [provider APIs and self-hosted models]

• Private health insurance
• Sports benefits
• Free English lessons (online)
• Local language courses
• Paid time off
• Maternity leave support
• Referral program rewards
• Upskilling, internal workshops, and participation in professional conferences and corporate events