Senior Backend Engineer PHP - API

We’re looking for a Software Engineer to join our newly-formed API team at Supermetrics. This team was created in 2025 with a bold mission to support an API-first transformation across the company. As an API Platform Engineer, you’ll have the opportunity to enhance the performance of our platform and the ways in which customers and internal teams interact with it. You will play a key role in:

• Building a Public API Platform: Developing robust, high-performance APIs that productize Supermetrics for our users. Your work will enable clients to build custom solutions, automations, and even SaaS products on top of our APIs without relying on our UI. In short, you’ll help unlock new ways for customers to use our product through well-crafted APIs.
• Implementing an API-First Culture: Shaping our internal shift towards an “API-first” approach by introducing and upholding standards, processes, and governance for both internal and external APIs. You’ll guide other teams in adopting best practices for API design, documentation (OpenAPI standards), and integration, ensuring consistency and quality across the organization.

Our API team is small, currently consisting of a senior engineer (Portugal), an engineering manager (Finland), and a product manager (UK). Being part of this new and growing team means you’ll play a crucial role in shaping technical decisions and team culture from the ground up.

Responsibilities:

In this role, you can expect a varied mix of activities. No two days are exactly the same, but your typical responsibilities will include:

• Collaborative Planning: Attending sync meetings (daily stand-ups, sprint planning, etc.) and working from our Jira board to understand priorities and resolve blockers. You’ll brainstorm with the team to break down big ideas into manageable tasks and design scalable solutions.
• Active Development: Diving deep into coding tasks – whether you’re implementing a new API feature, improving performance on a high-traffic service, or fixing a bug that’s slowing down another team. You’ll write clean, modern PHP/TypeScript/Go/Python code following best practices and ensure new changes integrate well with our existing systems.
• Pair Programming & Knowledge Sharing: Working closely with colleagues whenever you or they are stuck. You might pair programs to solve a tricky problem or review a critical piece of code. You’re willing to ask for help or offer it – we grow as a team by learning from each other.
• Quality Assurance: Ensuring your code is well-tested at all levels. You will write unit tests, integration tests, and end-to-end (e2e) tests as needed to guarantee reliability. If we encounter issues in production, you’ll help diagnose and fix them, and add tests to prevent regressions.
• Deployment & Monitoring: Owning your code from development to deployment. You’ll deploy services (via Docker/Kubernetes in our multi-cloud environment) and monitor them to ensure everything runs smoothly. If something goes wrong, you’ll investigate and resolve it – and you won’t rest until the new feature or fix is stable in production and delivering value.

Throughout all this, you will frequently interact with other teams. For example, you may coordinate with a front-end team consuming your API, or assist another backend team to adhere to the new API standards. Communication and cross-team collaboration are a big part of the job.

What Makes This Job Challenging (and Exciting!)

This role isn’t your average developer position – it comes with some unique challenges that will stretch your skills (in a good way):

• Complex Existing Systems: You’ll be working with a large, existing codebase that includes some legacy components and not-so-well-designed APIs. Untangling and improving this code to fit our new standards will be part of the challenge. If you are motivated by refactoring and simplifying complex systems, you’ll thrive here.
• High Traffic, High Stakes: Supermetrics products handle high traffic and large volumes of data, so performance and scalability are critical. Small changes can create significant effects. You’ll need to be mindful of efficiency and be ready to optimize code and queries for maximum performance.
• Cross-Team Collaboration: Our API team’s priorities will often involve enabling other teams. That means you’ll work closely with many departments whose own roadmaps may not always align with yours. You’ll need to negotiate, educate, and find win-win solutions so that our internal teams can progress with the help of your APIs and guidance. This requires understanding, tenacity, and proficient communication skills.
• Driving Cultural Change: Being an API-first evangelist means sometimes convincing others to change how they design software. You’ll be a key voice in promoting standards and best practices across the company. Driving this transformation is challenging – it involves documentation, training, code reviews, and sometimes tough conversations to prove the value of doing things the “new way.” If you’re up for steering change and can handle ambiguity, you’ll find this aspect very rewarding.

The flip side of these challenges is responsibility: you’ll directly affect the core platform that dozens of teams and thousands of customers rely on. If you’re looking for a role where you can leave a legacy and elevate an entire engineering organization’s practices, this is it.

Required Skills and Experience

We’re seeking a well-rounded engineer who meets the following qualifications:

Technical Must-Haves

• Modern PHP Skills: Professional experience with Object-Oriented PHP (version 8 or above). You write clean, maintainable PHP code and are familiar with the latest language features.
• Demonstrated ability to handle systems with high traffic and performance needs. You understand how to write efficient code and design systems that scale. Experience with profiling, caching, and optimizing queries or algorithms for speed and memory usage is important.
• Cloud-Native Technologies: Practical experience with containerization and orchestration tools such as Docker and Kubernetes. You should be comfortable building and deploying services in a modern cloud environment (knowledge of CI/CD pipelines and DevOps culture).
• API Design & Integration: Extensive experience in building and consuming APIs. You’re familiar with OpenAPI/Swagger specifications and have created or maintained API documentation. You have worked with third-party APIs and understand RESTful principles; having grappled with OAuth or other API auth methods adds value.
• Testing Mindset: Solid experience with automated testing at multiple levels – including unit testing, functional testing, integration testing, and end-to-end testing. You should be able to write tests to validate your work and ensure reliability for mission-critical systems.

Soft Skills Must-Haves

• Fast Learner & Growth Mindset: You can quickly pick up new concepts, domains, and technologies. More importantly, you have a committed will to improve and raise the bar for software engineering standards, security best practices, and processes across the company. You’re committed to identifying areas to improve.
• Open to Diverse Perspectives & Open-Minded: You have a good sense of humor and don’t take yourself too seriously. You appreciate constructive criticism, recognizing it as a pathway to better yourself. At the same time, you are qualified to challenge others when you see a better solution, and you can do so respectfully and constructively.
• Skilled Communicator: You can articulate complex technical concepts in a clear and concise manner, whether it’s explaining an idea in a design session or writing documentation for an API. You’re comfortable giving and receiving direct feedback. You know that transparent communication (tempered with respect) helps the team reach its objectives faster.
• Resourceful Problem-Solver: When faced with ambiguity or a tricky problem, you use critical thinking and creativity to find solutions. You don’t give up easily. If one approach fails, you come up with another. You enjoy solving puzzles and relish the chance to overcome challenges that don’t have a clear answer at first.
• Team Player: You work well with others and enjoy collaborating. You understand that our accomplishments are a team effort, especially since we enable many others through our work. You are approachable, help your colleagues, and are motivated to seek help yourself.

Nice-to-Have Skills

These aren’t deal-breakers, but if you have any of the following, be sure to tell us:

• Legacy Code & Refactoring: Experience working with legacy codebases or large monolith systems. Perhaps you’ve been involved in gradually refactoring a monolith into microservices, or you’ve maintained a product through major architectural changes. This experience means you won’t be intimidated by our existing code, and you know how to modernize it step by step.
• Additional Languages: Proficiency in TypeScript, Go or Python. Some components of our ecosystem use these languages, so the ability to read or write in them is a plus.
• Monitoring & Observability: Familiarity with observability tools and practices. For example, experience with OpenTelemetry instrumentation, and using monitoring dashboards (like Grafana) or APM tools to track system health and performance. Know how to set up alerts and interpret metrics to diagnose issues.
• AI Tools for Development: Knowledge of leveraging AI tools for coding (e.g., using AI coding assistants, AI code reviews, or use of AI for documentation). Being proficient with modern development aids shows you’re skilled and always looking for efficiency.
• Cloud-Native Ecosystem: Deeper understanding of cloud infrastructure beyond the basics. For instance, experience with cloud providers (AWS, GCP, etc.), CI/CD pipelines, or infrastructure-as-code. This overlaps with our required skills, but any extra cloud-native proficiency (networking, security, advanced Kubernetes features) will help.
• Willingness to Travel: Ability to occasionally travel for team gatherings or company off-sites. Since our team is distributed across Europe, we might get together a few times a year in one location to brainstorm and bond in person.

What You Can Expect in Your First 6 Months

We believe progress in this role means making steady advances as you ramp up. Here’s a rough outline of how your journey might look:

• Month 1-2: Onboarding and Learning. You’ll dive into our codebase and architecture, getting to know how data flows through Supermetrics and how our current APIs are structured. During this time, you’ll meet with stakeholders from other teams to understand their needs and gather context. You’ll start contributing by fixing some bugs or implementing small, well-scoped features – building confidence and familiarity with our systems.
• Month 3-4: Owning Features & Projects. As you grow more comfortable, you’ll take on medium-sized features or improvements. You might design a new API endpoint or refactor a part of the system with guidance from the team. You’ll be actively involved in technical discussions, offering suggestions and showing increasing technical knowledge.
• Month 5-6: Making a Big Impact. By now, you're handling your responsibilities proficiently. You’ll address some of our more challenging tasks or lead a project from design to deployment. You will also provide valuable feedback on our processes and perhaps mentor newer team members or share insights with the wider engineering group.

Benefits we offer:

• Attractive pay structure, including equity 
• Excellent work equipment and home office allowance for those working in our fully remote locations
• Health care benefits and leisure time insurance
• Personal learning budget
• Sports and wellbeing allowance

Hear why our team likes it here at supermetrics.com/careers/life-at-supermetrics

Does this sound like your next adventure? Apply now! We'll fill the role as soon as we find the right person.

For candidates located in Poland, please note that this role will be offered under an employment contract only.

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