Headquarters: Remote
URL: http://onthegosystems.com

We’re looking for a Senior Ruby on Rails developer with a curious, hands-on mindset who enjoys building reliable systems, owning meaningful features, solving complex problems, and using AI tools to improve development workflows, product quality, and user experience.

What you’ll be working on:

• Building and maintaining Ruby on Rails systems used at scaleOwning features from implementation to production

• Writing and maintaining automated tests (unit, integration, E2E)

• Investigating production issues, debugging complex problems, and helping design practical solutions

• Improving performance, reliability, and maintainability

What we’re looking for:

To succeed in this role, you’ll have:

• 4+ years of professional experience with Ruby on Rails

• Experience building and running production systems

• Strong backend skills, including databases, performance, and API design

• Solid experience writing and maintaining automated tests (including E2E)

• Curiousity about AI technologies and use AI-powered tools to improve productivity, debugging, testing, research, or development workflows.

Nice to have: 

• Experience with React 

• CI/CD, background jobs, or AWS experience

Why Join OTGS?

• Stable & self-funded: Founded in 2007, profitable, and independent.

• Industry leaders: Creators of WPML, the #1 multilingual plugin for WordPress, used on 1.5M+ sites

• Fully remote, async-friendly: Work from anywhere within EMEA hours

• Engineering-driven culture: Ownership, autonomy, testing, and thoughtful problem-solving

• Fair compensation and great benefits: Designed to support your well-being both inside and outside of work.

You’ll enjoy this role if you:

• Take pride in ownership and accountability

• Care about testing and long-term code quality

• Are motivated by solving problems in complex systems

• Enjoy collaborative environments where kind and experienced people learn, investigate issues, and solve problems.

Want to make a lasting impact on a product used by thousands of real customers? We would love to hear from you.

To apply: https://weworkremotely.com/remote-jobs/onthegosystems-senior-ruby-on-rails-developer-2

Headquarters:
URL: https://fairgambling.com

Blockchain Engineer / Analyst (Remote, Full-time or Contract)

About us – FairGambling We're a fast-growing platform in the online gaming space. Not a casino ourselves, but the layer on top of it: we review, compare, and analyze operators across the industry, with transparency as the whole point. A lot of what we cover happens onchain, so we don't take operator numbers at face value – we verify them. Player reviews are checked against real on-platform activity, not just star ratings. The goal is simple: give players the honest picture the industry usually doesn't.

The role A lot of what we verify lives onchain. We're hiring someone who's comfortable there – building tooling, tracking transactions across chains, and following contracts to surface what operators don't say themselves.

What you'll do:

• Build and maintain trackers, dashboards, and scripts

• Monitor multiple chains, track transactions, and follow contracts onchain

• Investigate transaction flows and surface insights for the research and content team

• Follow trails through data – the work is genuinely investigative

What we're looking for:

• Experience with trackers, dashboards, and scripts; smart contracts and transaction flows a strong plus

• Multi-chain experience ideally (EVM, Solana, BSC, TRON, etc.)

• Hands-on with blockchain explorers and analytics tools

• Background in a crypto product (exchange, DeFi) is a big plus

• Investigative mindset – you enjoy digging through data and following trails

To apply, please include:

1. Onchain tools, trackers, or investigations you've worked on (links / addresses welcome)

2. Your favorite analytics tool and something you've built or found with it

3. Your availability and preferred setup (full-time or contract)

To apply: https://weworkremotely.com/remote-jobs/fairgambling-blockchain-engineer-researcher

Headquarters: Slovenia
URL: http://bunny.net

Staff Software Engineer (Magic Containers)

Magic Containers is bunny.net’s edge-native platform for running containerized applications. It’s fast, flexible, and free from traditional cloud complexity. No Kubernetes. No YAML jungles. Just a simple, powerful way to deploy and scale apps globally with minimal setup.

It’s already running in production, powering real workloads, and we’re ready to take it further.

As a Staff Software Engineer, you’ll help evolve a platform that’s built for developers, with great DX, simple operations, and rock-solid reliability. You’ll work fast, ship often, and have a real voice in shaping the future of how containers run at the edge.

You’re a technical leader who shapes how we build at scale. You solve problems that cross teams, connect technical and business strategy, and make others better through influence, clarity, and mentorship. You set direction, not just follow it. And you leave every system and team stronger than you found them.

You won’t do it alone. You’ll work with people who challenge what’s possible and take pride in doing things well.

If this sounds like the kind of infrastructure you’d want to help others build with, we’d love to hear from you.

What will you do?

• Build and evolve the core of our edge-native container platform - Magic Containers and shape how developers build at the edge

• Multiply your impact by setting standards, mentoring engineers, and improving both code quality and team-wide knowledge

• Proactively spot opportunities to improve the platform, processes, or developer experience and drive those improvements end-to-end

• Lead cross-team efforts, whether it’s scaling orchestration systems, improving global observability, or driving company-wide migrations and technology shifts

• Align technical direction across teams by collaborating on specs, guiding architecture, and connecting engineering decisions to business goals

• Debug and resolve complex production issues, including those reported by customers

• Own outcomes end to end: not just shipping features, but delivering systems that solve real customer problems at scale

• Set a high bar for what great looks like in code quality, system design, and how we support what we build in production

What will you bring?

• 5+ years of experience with C# or a strong willingness to switch to it

• Deep understanding of containers (cgroups, namespaces, runtimes) and how they work under the hood

• Proven experience building and operating distributed systems across global infrastructure, especially those designed for global scale, low latency, or edge environments

• Strong Linux systems knowledge and comfort working close to the OS

• Solid grasp of networking fundamentals, including routing protocols, load balancing strategies, and distributed traffic patterns

• Familiarity with time-series or analytical databases like ClickHouse or InfluxDB

• Sharp debugging skills and the ability to diagnose complex production issues

• Experience leading cross-team or company-wide technical initiatives, guiding architecture, and mentoring engineers

• Understanding of observability best practices: including logging, metrics, and health monitoring for distributed systems

• Clear, thoughtful communication: you write great docs, explain trade-offs, and build alignment

• A customer-first mindset focused on outcomes, long-term reliability, and continuous improvement

• A desire to help others grow and a habit of leading by example in how you write and review code

What will make us extra happy?

• High-level understanding of Anycast: how it works, and how it impacts global routing, performance, and failover

• You’ve worked on sandboxing or container security (e.g. gVisor, Kata Containers)

• You’ve improved developer experience or infrastructure usability at scale

• Familiarity with message brokers like RabbitMQ or Kafka

• Hands-on with Redis, etcd, or other distributed key-value stores

• You've used bunny.net products or have experience with edge compute/CDN platforms

• You contribute to open source or share knowledge publicly (talks, posts, docs)

• You care deeply about developer experience and are thoughtful about the systems you design

• You bring curiosity, care, and energy to your work, and to the people around you

Not sure if you check every box?

That’s okay. We care more about how you think and what you’ve built than perfect credentials. If this work sounds exciting and you're ready to grow, we want to hear from you.

Where should you be located?

This job is fully remote from Europe (ideally CET or close time zone) with a flexible schedule, to make our collaboration easier. You’re still free to hop around the world and switch up your scenery whenever you want.

What's in it for you?

Life at bunny.net comes with benefits that make work (and life) better.

• 100% flexible hours - Your work, your rhythm. Whether you thrive at 3 am or on a beach at noon, we've got you.

• Remote-first by design - No offices, no commute, just the freedom to work anywhere. Miss the office? We’ll give you a 3-night voucher for visiting our headquarters.

• Performance-based bonuses - Great work pays off, and we reward impact annually.

• Medical, dental, and vision insurance - Coverage worldwide.

• Paid time off - Love the slopes or the sea? Enjoy them with 25 vacation days, plus an extra loyalty day each year, capped at 5 years (30 days total), on top of your local public holidays.

• Meeting-free Thursdays - We keep Thursdays meeting free internally so you can focus on deep work without interruptions.

• Home office budget - We believe everyone is more efficient working in a comfortable office, and we're happy to help you set it up with an annual budget of €500.

• Paid sick leave - Feeling ill? Take time off to fully recover without having to worry about your finances.

• Parental leave - Paid 16 weeks for birthing parents, 8 weeks for non-birthing parents. If your country gives more, that’s your baseline. If it gives less, we top it up. Take your leave all at once or split it across the first year for maximum flexibility. After paid leave, your local statutory rules apply.

• Annual fluffle-building - We're remote, but not distant! Once a year, we meet in a sunny location where virtual high-fives turn into real ones.

• Employee Stock Option Plan (ESOP) - Everyone at bunny.net gets a piece of the pie, starting with 0.01% equity.

• Mental health support - Feeling down? We've got your back. bunny.net provides mental health resources and help via BetterHelp.com.

• Wellness budget - An annual well-being budget of €480 is here to help you stay fresh and focused.

• Educational budget - €500 yearly for books, seminars, or online courses to keep your learning on track, work-related or not.

• Music on us - Work is better with music. Enjoy a yearly Apple, Spotify, or YouTube Premium subscription on us.

To apply: https://weworkremotely.com/remote-jobs/bunny-net-staff-software-engineer-magic-containers

Headquarters: Chicago, IL
URL: https://praiahealth.com

You'll build and scale the platform services that power Praia's consumer health products, with a particular focus on EMR integration, including FHIR connectivity to Epic and other systems. You'll own end-to-end delivery of secure, well-documented APIs used by both internal teams and external health-system partners.

This is a senior-level role with real ownership over complex systems. If you've integrated with healthcare systems before and want to do it alongside people who take both engineering quality and patient experience seriously, we want to chat.

What you'll do

• Design and operate EMR integration services using HL7 FHIR APIs and adjacent integration patterns (Epic, MyChart, others)
• Build secure APIs with strong authentication and authorization, audit trails, and least-privilege defaults
• Use Databricks / Apache Spark for data engineering work as needs arise — pipelines, jobs, Delta Lake — to support product and integration use cases
• Produce and maintain developer documentation that engineers actually want to read: OpenAPI specs, integration guides, runbooks
• Lead code and design reviews; mentor engineers and unblock the team
• Implement automated unit and integration testing, and promote pragmatic TDD standards
• Operate with a DevOps mindset: CI/CD, infrastructure-as-code, observability, on-call readiness
• Partner with Product, Design, and Customer teams to turn requirements into reliable systems

What we're looking for

• 5+ years building and operating production software, with senior- or staff-level scope and ownership of complex systems
• Strong programming skills in one or more of: Java/Kotlin, TypeScript/Node.js, Python (or similar)
• Hands-on experience integrating with EMR/EHR systems
• Experience designing and delivering cloud-native services on AWS, Azure, or GCP, including Kubernetes-based deployments
• Solid grounding in OAuth2/OIDC, mTLS, JWT, secrets management, and secure SDLC practices
• Comfort with CI/CD, build automation, and infrastructure-as-code — and owning your own release and operational processes
• Hands-on observability experience: logging, metrics, tracing, APM tools, and data-driven incident response
• Databricks experience: jobs and workflows, notebooks, Delta Lake, data pipelines
• Strong written and verbal communication — able to write clear technical designs and present to senior stakeholders
• Bachelor's degree in CS / Engineering, or equivalent practical experience

Bonus points

• Open-source contributions
• Patents, publications, or conference presentations
• Prior experience at a healthcare or health-tech company

Benefits

• Competitive base salary and performance-based bonuses
• Full medical, dental, and vision coverage
• Company-paid life insurance and short- and long-term disability
• 401(k) with company matching
• Flexible PTO
• Employee wellness programs and resources
• A supportive and inclusive remote-friendly work environment

To apply: https://weworkremotely.com/remote-jobs/praia-health-senior-backend-engineer

Headquarters: Chicago, IL
URL: https://praiahealth.com

To apply: https://weworkremotely.com/remote-jobs/praia-health-inc-staff-software-engineer-data-infrastructure

Headquarters: Zuerich
URL: https://en.comparis.ch/

To apply: https://weworkremotely.com/remote-jobs/comparis-ch-backend-engineer-80-100-f-m-x

Headquarters: Remote
URL: https://stripe.com

Stripe is looking for a senior backend engineer to help build the financial infrastructure of the internet. You'll work on scalable systems that handle millions of transactions per day.

• 5+ years of backend engineering experience
• Strong proficiency in Ruby, Go, or Java
• Experience with distributed systems and microservices

To apply: https://weworkremotely.com/remote-jobs/stripe-senior-backend-engineer

Headquarters: Washington, DC
URL: https://urbanlegend.co/

LOCATION REQUIREMENTS (NO EXCEPTIONS)

Remote: Must reside in Texas, USA

We are unable to consider candidates outside of Texas for this remote role.

ROLE DESCRIPTION

This is a full-time Backend Engineer role reporting directly to the CTO, open to either a late mid-level engineer ready to level up or a solidly senior engineer looking for ownership and impact. Title and comp will be calibrated to experience. You'll have direct access to senior technical leadership and a real voice in shaping our architecture and roadmap with no layers in between.

You will design, develop, and maintain the scalable backend services that power Urban Legend's campaigns, creator tools, and conversion tracking. You'll work across a polyglot stack, primarily Python/Django and Ruby/Rails, and contribute to an active migration of our infrastructure from Heroku to Render. You'll partner closely with product, design, and front-end engineers to ship customer-facing features end-to-end.

We move fast, ship often, and use modern AI tooling (Cursor in particular) as a core part of our day-to-day workflow. Above all, we are looking for someone with a strong bias toward action. You'd rather ship something today, learn from it, and iterate than spend a week debating the perfect approach.

WHAT YOU'LL WORK ON

Our backend ecosystem includes:

• A Django/DRF monolith (Postgres, Redis, RQ workers, Docker)

• Two Ruby on Rails services (Rails 7/8, Postgres, Puma)

• A Flask service for high-throughput conversion tracking

• A Node.js/TypeScript service (Express, Drizzle, Playwright/Puppeteer)

• Shared infrastructure across Docker, Postgres, Redis, and AWS — currently in the middle of a Heroku → Render migration

REQUIRED QUALIFICATIONS

• A strong bias toward action. You ship, you measure, you iterate. You don't get stuck in analysis paralysis, and you're comfortable making good-enough decisions with incomplete information.

• Strong, production-level expertise in either Python/Django or Ruby on Rails. You don't need both on day one, but you should be excellent in one and excited to ramp quickly on the other.

• Demonstrated ability to learn unfamiliar frameworks and languages quickly. We'll occasionally need you in Flask, Node/TypeScript, or wherever the work lives.

• Solid fundamentals in OOP, relational databases (Postgres), REST API design, background job processing, and caching (Redis).

• Comfortable working in Docker-based local and production environments.

• Experience building scalable, high-performance, secure backend systems.

• Strong collaboration skills in a remote/hybrid environment, with exceptional problem-solving ability and attention to detail.

• Active, hands-on experience with AI coding tools, particularly Cursor, and a point of view on how to use them effectively.

• Bachelor's degree in CS, Engineering, or a related technical field, or equivalent professional experience.

STRONGLY PREFERRED

• Infrastructure / platform experience — you're a product engineer first, but you've spent time on a platform team or otherwise have meaningful DevOps chops. We are looking for someone who can add real value to our Heroku → Render migration, not a pure DevOps hire who can't ship product work.

• Hands-on experience with Render, Heroku, or similar PaaS platforms.

• Experience with CI/CD pipelines, container orchestration, observability (Sentry, logging, metrics), and zero-downtime deploys.

• Familiarity with AWS (S3, Lambda, etc.).

• Front-end literacy sufficient to integrate cleanly with our React/TypeScript clients.

NICE TO HAVE

• Experience with creator / marketing / ad-tech platforms.

• Experience with payments (PayPal, Stripe, Brex, etc.).

• Experience with web scraping, headless browsers (Playwright/Puppeteer).

BENEFITS:

• Industry competitive compensation with significant opportunities for growth
• Health benefits package
• Unlimited PTO

To apply: https://weworkremotely.com/remote-jobs/urban-legend-backend-engineer-mid-senior

Headquarters: Nepal
URL: https://fusemachines.com/

To apply: https://weworkremotely.com/remote-jobs/fusemachines-applied-ai-engineer-automation

Headquarters: Sweden
URL: https://newsroom.spotify.com/company-info/

To apply: https://weworkremotely.com/remote-jobs/spotify-senior-machine-learning-engineer-personalization

Headquarters: California, US
URL: https://www.chess.com/about

About You

You believe in the power of ML and AI to build amazing, interesting, and insightful products and services for humanity… and you’d love to do that in chess!

What you'll do

• Own ML-driven product features, identifying opportunities through to modeling, deployment, experimentation, and impact.
• Partner with Product, Leadership, Growth, and Data Science to determine which problems should (and shouldn’t) be solved with ML, define success metrics, and iterate based on real-world performance.
• Design, build, and ship scalable ML systems, including data pipelines, training workflows, and production model serving infrastructure.
• Prototype rapidly and iterate regularly, developing repeatable evaluation frameworks, running experiments, and improving models based on results
• Shape our ML architecture and MLOps practices, establishing standards for experimentation, deployment, monitoring, and retraining as we scale.
• Drive innovation in Generative AI, exploring how we can best use LLMs and agents to power new user experiences and internal productivity tools.
• Provide technical leadership and mentorship, mentoring more junior team members, influencing our roadmap, and raising AI/ML literacy across the company.

Preferred Skills

• 5+ years of demonstrated, hands-on experience building scaled ML systems, training large ML models, or equivalent experience.
• 1+ year of AI engineering experience.
• Strong technical skills and judgment around coding, testing, and building for scale.
• Strong practical ML knowledge, solid knowledge of ML theory, and a working understanding of the AI application stack and lifecycle in the context of foundation models, from evaluation to deployment.
• High sense of ownership and a drive to deliver impact in a fast-paced, evolving, ambiguous environment.

About the Opportunity

• This is a full-time opportunity
• We are 100% remote (work from anywhere!)

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You can learn more about us here:

• https://www.chess.com/article/view/how-chess-com-virtual-team-works-together
• https://www.chess.com/about

To apply: https://weworkremotely.com/remote-jobs/chess-com-senior-ml-engineer