Jobs Ruby

We are looking for experienced RoR Developer (2+ years) to train AI coding models.

This is not a classic software development role. You will work with real repositories and analyze AI-generated code, finding bugs, edge cases, architectural mistakes, and other failures that an experienced engineer would catch.

What you’ll do

• Work with anonymized real-world repositories.
• Review and test AI-generated code.
• Test and evaluate agentic coding models designed to perform complex engineering tasks at a senior developer level.
• Focus on creative problem-finding rather than traditional feature shipping. 

Requirements

• 2+ years of software engineering experience.
• Use AI tools (AI agents, Claude Code, Cursor, Codex or similar) in daily workflow.
• Ability to work independently.
• Strong debugging and code-review skills.
• Legacy-code experience is a plus.
• Education in Computer Science or a related field is a plus.
• English B1+.

You will be part of building better AI systems by helping improve the quality, accuracy, and reliability of the answers they provide.

We are looking for a Senior Ruby on Rails Developer to join a product engineering team working on a mature, high-traffic platform with a large and well-established domain model.

Working Hours:
During the initial months, this role follows the US Eastern Time (EST) schedule, with working hours until approximately 00:00–01:00 Kyiv time. After a few months, the schedule shifts to partial overlap with the US team, working until approximately 20:00–21:00 Kyiv time.
 

Project: A long-running digital platform in the travel, hospitality, and marketplace domain. The product manages complex workflows around properties, reservations, deposits and exchanges, billing, and member onboarding. You'll work on a large Ruby on Rails application, contributing to new features, performance improvements, integrations, and the continuous evolution of the platform.
This is a backend-focused Rails role. You'll work primarily with Ruby on Rails, databases, background processing, APIs, and third-party integrations while contributing to a large and established codebase.
 

Tech Stack: Ruby, Ruby on Rails 7.x, Rails Engines, MySQL, Redis, Memcached, Solr, Sidekiq, Clockwork, ActionCable, ActiveAdmin.
Authentication & Security: JWT, CanCan, bcrypt, role-based authorization.
Integrations: Stripe, AWS S3/CloudFront/SNS, Twilio, transactional email, product analytics, feature flags, geolocation.
Testing: Minitest, RSpec, FactoryBot, VCR/WebMock, Capybara/Selenium.
 

     Responsibilities:

• Develop and deliver backend features using Ruby on Rails;
• Work effectively with a large, established Rails codebase and make well-tested, maintainable changes;
• Design and implement database changes, models, service objects, APIs, and business logic;
• Develop and maintain background jobs and scheduled processes using Sidekiq and related tools;
• Build and maintain integrations with third-party services such as Stripe, AWS, and Twilio;
• Write and maintain automated tests, including unit, integration, and API tests;
• Analyze and optimize application performance across the database, search, caching, and background processing layers;
• Contribute to improving system reliability, code quality, and maintainability;

• Participate in code reviews and collaborate closely with other engineers and product teams.

   

  Requirements:

• 4+ years of professional experience with Ruby on Rails, including production experience with large, established applications;
• Strong experience with Ruby on Rails 7.x;
• Solid knowledge of MySQL and/or PostgreSQL, including schema design, migrations, indexing, and query optimization;
• Strong experience with Sidekiq or similar background job processing tools;
• Experience building and maintaining RESTful APIs;
• Experience integrating third-party services and APIs;
• Strong testing experience with Minitest/RSpec and related testing tools;
• Experience with Git and pull-request workflows;
• Comfortable working with and improving a large, long-lived codebase;

• Good written English and clear communication skills.
   

  Nice to Have:

• Experience with JavaScript, Vue, Stimulus, or Hotwire;
• Experience with HTML, CSS, and Sass;
• Experience with Solr, Elasticsearch, or other full-text search technologies;
• Experience with Stripe or other payment and billing integrations;
• Experience with ActiveAdmin or similar admin frameworks;
• Familiarity with Docker and Kubernetes;
• Familiarity with CI/CD, including CircleCI or GitHub Actions;
• Familiarity with AWS, particularly S3, CloudFront, or SNS;
• Experience with monitoring and observability tools such as Prometheus or APM solutions;
• Experience with Playwright or other browser E2E automation tools;
• Experience maintaining Rails Engines or modularizing a monolith;
• Experience in travel, hospitality, or marketplace products.

Metamindz is a UK-based technical consultancy - CTO-led software development, fractional CTO services, and technical recruitment for startups and scaleups across the UK, US, and Middle East. Every project is run by real developers and CTOs rather than non-technical account managers, so engineers here work directly on real products and real technical problems.

We're looking for a Fullstack Engineer to join our work with UK-based smart locker technology company building software and hardware systems for automated collections, returns, and asset handovers.

This is a hands-on product engineering role where backend reliability matters as much as frontend quality. You'll be working across the application stack, while also dealing with the interesting boundary between software and physical hardware. The role is best suited to someone who is technically solid, easy to work with, and comfortable taking ownership without needing to be micromanaged.

Who we're looking for:

• Strong backend experience first - Ruby on Rails is the key requirement
• Solid fullstack experience with React and Next.js
• Comfortable working with ERB templates, as they are still heavily used in the product
• Good understanding of databases and data integrity - PostgreSQL preferred, MySQL also fine
• Basic AWS and DevOps knowledge - you should be comfortable deploying and operating applications, but you won't be expected to rebuild Kubernetes clusters
• Good understanding of APIs and integrations, with the ability to reason about how software communicates with external systems and hardware
• 3-5+ years of commercial development experience is ideal; strong candidates with around 2 years can also be considered based on their experience and client feedback
• Strong communication and a good attitude are essential - we'd take a great communicator who solves problems over a more senior developer who is difficult to work with
• Comfortable working independently, responding reliably, and collaborating closely with the wider team

What you'll work on:

• Building and maintaining Ruby on Rails backend functionality
• Working across React, Next.js and ERB-based frontend code
• Designing and working with APIs that connect the platform to external systems and hardware
• Working with PostgreSQL and ensuring data remains reliable and consistent
• Deploying and maintaining applications in AWS
• Debugging issues across the full stack, from frontend behaviour through to backend logic, databases and hardware integrations
• Working on features that interact with real-world locker hardware, where software reliability has a direct operational impact
• Collaborating with the development team to solve problems and ship production software

Nice to have:

• MQTT or other messaging / IoT experience
• Previous experience working with connected hardware or physical devices
• Experience with other cloud platforms or DevOps tooling
• Experience working in a startup, agency or product consultancy environment

What we offer:

• The opportunity to work on a real product combining software and connected hardware
• Direct collaboration with experienced engineers and CTOs
• Real production work used across retail, warehouse and workplace environments
• A role with genuine ownership across the stack rather than a narrow frontend or backend position
• A technically interesting mix of web development, APIs, databases, cloud infrastructure and hardware integrations
• A collaborative environment where communication and problem-solving matter as much as technical seniority
• The opportunity to work on a product where software directly controls and tracks real-world operations

Who We Are

PAR Retail, with its Open Commerce® product suite and patent pending Wallet Steering® System, empowers Convenience & Fuel Retailers to gain more share of wallet and customer lifetime value than possible with any other solution provider. PAR Retail’s unified Open Commerce product suite consists of: Activate for Intelligent 1:1 Loyalty, Transact for Contactless Commerce, and Experience for Cross-Channel Customer Experiences. PAR Retail’s solutions are supported by a set of subscription-based program management services and are contractually backed by its 1.5X Performance Guarantee.

Technology Stack:

Ruby, Ruby on Rails, Postgres, Redis, Sidekiq, GraphQl, RabbitMQ

Requirements:

- Practical experience building systems in Ruby on Rails

- At least 6 years industry experience or equivalent

- Experience building and maintaining backend APIs, including design, implementation, evolution, and maintenance

- Familiarity with TypeScript, or similar modern strongly-typed language

- Proficiency using a variety of database technologies, both relational and non-relational

- Strong understanding and familiarity with CI/CD pipelines and automated tests

- An ability to work in service-based architectures as well as well-factored Rails monolith applications

- Highly independent and able to effectively self-organize and prioritize work

- The ability to write clean code, and the discipline to write effective automated tests to deliver high-quality system improvements

- An ability to effectively break down larger bodies of work for delivery as a series of small, self-contained changes to the system

- Excellent spoken and written communication skills

- BS/MS degree in Computer Science, Engineering, or equivalent years of professional working experience

Bonus Points

- Experience with NodeJS and React

- Experience in the retail and/or fuel & convenience industries

- Experience working in distributed teams

- Experience with Nest.js and/or GraphQL

Responsibilities:

- Collaborate closely with other Engineers, design and implement new functionality based on product objectives and requirements.

- Work with the broader product engineering team to plan and coordinate feature and functionality improvements, as well as resolve bugs and execute technical enhancements, that cross-cut large parts of our platform.

- Work to continually learn, improve technology skills, expand knowledge of the our platform technologies, and gain increasing versatility across the breadth of our platform systems.

- Expand APIs and business logic, and as needed write or revise customer-facing API documentation.

- Work with our infrastructure team to enable and enhance highly-available, performant, and well-instrumented backend applications and services that run in our customer environments at substantial scale.

- Support operations and infrastructure teams for issue resolution on relevant applications or services running in production environments.

PAR Retail Offers:

- Long-term employment;

- Competitive compensation with regular performance-based salary and career development reviews;

- Paid vacations and sick leaves;

- Flexible working hours;

- A unique and friendly environment where everyone can explore and learn new technologies.

We are a marketplace where users can compare personalized, prequalified rates and quotes from multiple lenders and carriers, for student loans, mortgages, personal loans, and insurance. 

We’re challenging the status quo by giving power to the consumer. We believe in a world where ‘ethical’, ‘lending’, and ‘insurance’ can coexist, so we set out to build innovative platforms that actually work for customers. Our mission is to help people find the best loan or insurance policy possible. 

We believe researching and buying loans or insurance shouldn’t be confusing or complex, so we’ve focused on simplicity. We’ve created the only unbiased loan and insurance buying process out there, which makes finding options straightforward and clear. 

Responsibilities

• Build and maintain backend services
• Build and maintain shared code libraries in Ruby and Javascript
• Maintain and evolve our microservice architecture, including Kafka and GraphQL APIs
• Design and build improvements to our development processes, including testing strategy
• Support and troubleshoot production systems
• Determine operational feasibility by evaluating, analysis, problem definition, requirements, solution development, and proposed solutions
• Participating in the code reviews and design discussions with other engineers
• Have a strong sense of end to end ownership
• Adhere to key principles: Code and design for best performance, scalability and resiliency
• Participate in Agile planning and standup meetings
• Participates in the testing process through test review and analysis, test witnessing and certification of software
• Be a self-starter, capable of solving ambiguous and challenging technical problems with wide scope
• Deliver trustworthy solutions for engineers allowing them to focus on experimentation, evolution, and delivery of high-quality features
• Collaborate cross-functionally with data scientists, business users, project managers and other engineers to achieve elegant solutions
• Backend development including design, documentation, implementation, and testing
• Work alongside other engineers on the team to elevate technology and consistently apply best practices

Skills Required

• 5+ years experience with back-end development using Ruby on Rails.
• Experience building API base applications.
• Understand data structure and distributed system microservice concepts
• Understanding of the web stack, including HTML/CSS, Javascript, JSON, HTTP requests.
• Experience with Relational Databases and SQL (MySQL preferred).
• Bachelor's degree in Computer Science, Computer Engineering, or equivalent experience.
• English - active intermediate level or higher.

Nice to have:

• Experience with GraphQL.
• Familiarity with cloud platforms and services (AWS preferred) for deploying and managing applications.
• Experience with RSpec or similar unit test frameworks for RoR.
• Understanding Agile methodologies and CI/CD best practices.
• Being ready to work with FE is a plus.

Overview:

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.

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:

Ruby 3.x, Rails 7/8, PostgreSQL, Redis, Sidekiq, Kafka [/RabbitMQ], Docker, Kubernetes, GitLab CI, Grafana, Sentry.

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

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

Our Benefits:

• Full-time remote work opportunities and flexible working hours
• Private insurance
• Additional 1 Day Off per calendar year
• Sports program compensation
• Comprehensive Mental Health Programme
• Free online English lessons with a native speaker
• Generous referral program
• Training, internal workshops, and participation in international professional conferences and corporate events.

Workload: full-time, remote
Start: asap
Duration: long and fixed-term (~9–12 months) but with a right to a 8 week notice period
Location: Poland !!!
English: B2

Important info:
Client is very technical and knows who they are looking for, has to be Poland based, max 2-3 hours travel to Wrocław as they have a small team in Wrocław, Poland. Mid + senior profiles are okay.

The Role
A backend-focused engineering position on a transformation project for an international travel company. The engineer will own features end-to-end - from planning and design through building, testing, and release.

Key Responsibilities

• Own features end-to-end (plan, design, build, test, release)
• Build and maintain Ruby on Rails systems
• Contribute to full-stack work (Rails-heavy, with frontend involvement as needed)
• Write tested, high-quality code
• Use AI coding agents to maximize efficiency
• Participate in code reviews
• Maintain systems and resolve production issues
• Collaborate with Product, Design, and Quality Engineering teams

Required Qualifications

• Proficiency in Ruby on Rails with production experience
• Strong database schema design and data modeling skills
• RESTful API design experience
• PostgreSQL and AWS infrastructure knowledge
• Demonstrable experience with AI coding agents, or strong enthusiasm to adopt them
• Good English
• Team-oriented with strong communication skills
• Pragmatic about speed/quality/scope tradeoffs

Tech Stack
Ruby on Rails, PostgreSQL, AWS, Next.js, Vercel. Trunk-based development with CI/CD and multiple daily deployments.

Nice to Have

• E-commerce or travel platform experience
• An eye for UX/design
• Travel enthusiasm

A backend-focused engineering position on a transformation project for an international travel company. The engineer will own features end-to-end - from planning and design through building, testing, and release.

Key Responsibilities 

-Own features end-to-end (plan, design, build, test, release) 

-Build and maintain Ruby on Rails systems 

-Contribute to full-stack work (Rails-heavy, with frontend involvement as needed) 

-Write tested, high-quality code 

-Use AI coding agents to maximize efficiency 

-Participate in code reviews 

-Maintain systems and resolve production issues 

-Collaborate with Product, Design, and Quality Engineering teams

Required Qualifications 

-Proficiency in Ruby on Rails with production experience 

-Strong database schema design and data modeling skills 

-RESTful API design experience 

-PostgreSQL and AWS infrastructure knowledge 

-Demonstrable experience with AI coding agents, or strong enthusiasm to adopt them 

-Good English 

-Team-oriented with strong communication skills 

-Pragmatic about speed/quality/scope tradeoffs

Tech Stack 

-Ruby on Rails, PostgreSQL, AWS, Next.js, Vercel. Trunk-based development with CI/CD and multiple daily deployments. 

Nice to Have 

-E-commerce or travel platform experience 

-An eye for UX/design 

-Travel enthusiasm

We offer:

• Attractive financial package

• Challenging projects

• Professional & career growth

• Great atmosphere in a friendly small team

We are looking for a Senior Ruby on Rails Developer to join a product engineering team working on a mature, high-traffic platform with a large and well-established domain model.

Project: A long-running digital platform in the travel, hospitality, and marketplace domain. The product manages complex workflows around properties, reservations, deposits and exchanges, billing, and member onboarding. You'll work on a large Ruby on Rails application, contributing to new features, performance improvements, integrations, and the continuous evolution of the platform.

Ability to maintain several hours of overlap with the CDT time zone.
 

This is a backend-focused Rails role. You'll work primarily with Ruby on Rails, databases, background processing, APIs, and third-party integrations while contributing to a large and established codebase.
Tech Stack: Ruby, Ruby on Rails 7.x, Rails Engines, MySQL, Redis, Memcached, Solr, Sidekiq, Clockwork, ActionCable, ActiveAdmin.
Authentication & Security: JWT, CanCan, bcrypt, role-based authorization.
Integrations: Stripe, AWS S3/CloudFront/SNS, Twilio, transactional email, product analytics, feature flags, geolocation.
Testing: Minitest, RSpec, FactoryBot, VCR/WebMock, Capybara/Selenium.
 

Responsibilities:
Develop and deliver backend features using Ruby on Rails;
Work effectively with a large, established Rails codebase and make well-tested, maintainable changes;
Design and implement database changes, models, service objects, APIs, and business logic;
Develop and maintain background jobs and scheduled processes using Sidekiq and related tools;
Build and maintain integrations with third-party services such as Stripe, AWS, and Twilio;
Write and maintain automated tests, including unit, integration, and API tests;
Analyze and optimize application performance across the database, search, caching, and background processing layers;
Contribute to improving system reliability, code quality, and maintainability;
Participate in code reviews and collaborate closely with other engineers and product teams.
 

Requirements:
-5+ years of professional experience with Ruby on Rails, including production experience with large, established applications;
-Strong experience with Ruby on Rails 7.x;
-Solid knowledge of MySQL and/or PostgreSQL, including schema design, migrations, indexing, and query optimization;
-Strong experience with Sidekiq or similar background job processing tools;
-Experience building and maintaining RESTful APIs;
-Experience integrating third-party services and APIs;
-Strong testing experience with Minitest/RSpec and related testing tools;
-Experience with Git and pull-request workflows;
-Comfortable working with and improving a large, long-lived codebase;
-Good written English and clear communication skills.

Nice to Have:
Experience with JavaScript, Vue, Stimulus, or Hotwire;
Experience with HTML, CSS, and Sass;
Experience with Solr, Elasticsearch, or other full-text search technologies;
Experience with Stripe or other payment and billing integrations;
Experience with ActiveAdmin or similar admin frameworks;
Familiarity with Docker and Kubernetes;
Familiarity with CI/CD, including CircleCI or GitHub Actions;
Familiarity with AWS, particularly S3, CloudFront, or SNS;
Experience with monitoring and observability tools such as Prometheus or APM solutions;