Senior Software Engineer (JVM, Kotlin) in City of London

Simple Machines is a leading independent boutique technology firm with a global presence, including teams in London, Sydney, San Francisco, and New Zealand. We specialise in creating technology solutions at the intersection of data, AI, machine learning, data engineering, and software engineering. Our mission is to help enterprises, technology companies, and governments better connect with and understand their organisations, their people, their customers, and citizens. We are a team of creative engineers and technologists dedicated to unleashing the potential of data in new and impactful ways. We design and build bespoke data platforms and unique software products, create and deploy intelligent systems, and bring engineering expertise to life by transforming data into actionable insights and tangible outcomes.

The Role: As a Senior Full Stack Engineer at Simple Machines, you’ll be at the heart of groundbreaking projects, collaborating closely with both our talented internal team and forward-thinking clients. In this hands-on role, you'll drive the development of sophisticated, scalable solutions across the full technology stack—from intuitive frontends and robust backends to powerful data pipelines and resilient infrastructure. If you’re passionate about solving complex problems and pushing the boundaries of what’s possible, this role offers the perfect platform for you to make a real impact.

Technical Responsibilities:

• Responsible for design and technical development of backend services for a highly scalable marketing platform.
• Responsible for designing the APIs, applications, and infrastructure the team develops, and documenting the technical requirements and design for the client.
• Responsible for end-to-end delivery and support, including build, automation, deployment, and operations, for everything that is developed.
• Partner with client stakeholders, and team members, to gather business requirements, collaborate on design decisions, and translate them into technical and design requirements.
• Operate within an iterative delivery team using Agile delivery tools and practices.
• Hybrid remote and in-person collaboration with the delivery team and client stakeholders.

About the team: At Simple Machines we are passionate about technology and engineering, we have a strong engineering culture and this is an opportunity to join a high-performing engineering team working on an exciting project building a large-scale machine learning platform for a global telecommunications company. Each team member has varying degrees of strength in each area, but all work together across the full stack and assist one another to learn and contribute. The engineering team enjoys a high degree of autonomy over technical design and actively engages with stakeholders to design solutions. They also actively engage with data scientists and other teams to design and document cross-system solutions.

What we are looking for:

• A consultative approach to software development and software engineering.
• Core foundation in programming, especially in JVM languages (particularly Kotlin or Java).
• Experience designing and implementing data-driven APIs.
• Exposure to frontend development (particularly React.js, Tailwind, REDUX, Typescript).
• Past project experience with large scale web services.
• Cloud infrastructure experience with AWS and/or Google Cloud, Azure, etc.
• Infrastructure-as-code experience, such as with Terraform or Cloud Formation.
• In-depth experience with unit and integration testing, and test automation generally. Ideally TAA and/or BDD.
• Experience working with SQL databases in the context of implementing data-driven APIs, and designing database schemas and queries to meet business requirements.
• A passion and proven background in picking up and adopting new technologies on the fly.
• Exposure to Scala, or functional programming generally.
• Exposure with highly concurrent, asynchronous backend technologies, such as Ktor, http4k, http4s, Play, RxJava, etc.
• Exposure with DynamoDB or similar NoSQL databases, such as Cassandra, HBase, BigTable, or Cosmos DB.
• Exposure with Git workflows, and the ability to tailor the workflow to project needs.
• Exposure with containerised application deployment using Docker, Amazon ECS, Kubernetes, etc.

What We Offer in the UK:

• Salary: Competitive salary and benefits package.
• Join a fast growing team - 30% growth in the last 12 months.
• Hybrid working environment, 1-2 days in the London office.
• Pension: Up to 5% employer contribution, matching up to a 5% employee contribution, for a total of up to 10%.
• Annual Leave: 4 weeks standard + 1 week additional annual leave over Christmas shut down period, plus public holidays.
• Health and Wellbeing Allowance: £1,250 allowance per year to be used for any food and non-alcoholic beverages during business hours, healthcare, gym memberships, sporting goods and accessories, and any wellness appointments.
• Professional Development: £1,500 annual budget for training, courses, and conferences, with potential for additional funding.
• Certifications: £2,500 annual budget for certifications and related courses.
• Equipment Allowance: £1,500 for UK team members, plus Apple MacBook Pro laptops and necessary accessories.
• Company Sick Leave: 10 days per annum, includes coverage for employee’s family.
• Antenatal Support: Paid time off for antenatal appointments, including classes recommended by health professionals.
• Terminal Illness Benefit: Three months' continuance of salary at full pay.