Senior Software Developer

As a Senior Software Developer, you will take end-to-end ownership of delivering high-quality software, from discovery and technical design through to implementation, testing, release, and operational excellence.

You will work closely with Product, UX, Test Automation, and DevOps to deliver customer-focused solutions, while also acting as a senior technical voice within the team. You'll help raise engineering standards through mentoring, constructive code reviews, and thoughtful technical decision-making.

While this role has no formal line-management responsibility, it carries significant technical influence. You will help shape architectural direction, engineering standards, and ways of working as the platform evolves., * Design, build and maintain backend services and customer-facing features with a strong focus on reliability, security and performance.

• Architect solutions and evolve systems incrementally - balancing speed, quality, cost, and operational simplicity.

• Champion an API-first mindset: design clean, versioned APIs and integrations with clear contracts and documentation.

• Build event-driven workflows using AWS messaging and orchestration (SQS/SNS/Step Functions) and serverless patterns.

• Deliver robust data solutions across operational stores and the warehouse (SingleStore), including high-volume data processing and reporting use cases.

• Implement and maintain automated testing at multiple levels (unit/integration/E2E) and contribute to a healthy testing strategy.

• Contribute to performance testing and capacity thinking using k6 and production observability signals.

• Participate in code reviews and help maintain engineering standards and best practices.

• Work in a cross-functional agile team - collaborating with Test Automation, DevOps and UX to deliver outcomes.

• Mentor other engineers through pair programming, coaching, and knowledge sharing.

• Instrument services with meaningful telemetry (logs/metrics/traces) and build dashboards/alerts so teams can observe health and user impact in production.

• Monitor and optimise cloud cost-to-serve: understand cost drivers, review spend impact of changes, and implement pragmatic cost controls and optimisations.

• Contribute to operational reviews post-release (incidents, regressions, cost spikes) and drive follow-up actions to improve stability and efficiency.

You enjoy working in an agile environment and actively contribute to refinement, planning, stand-ups, demos, and retrospectives.

You think in terms of outcomes rather than tickets, taking responsibility for seeing work through from problem definition to production impact and ongoing operational health.

You take ownership, proactively identify risks and blockers, and drive pragmatic, well-reasoned solutions.

You value quality and automate where it provides leverage, across testing, tooling, CI/CD, and operational workflows.

You communicate clearly and confidently, particularly through written communication, whether documenting decisions, reviewing code, or collaborating asynchronously across teams.

You are comfortable reviewing pull requests and providing clear, constructive, and actionable feedback that helps improve code quality, consistency, and shared understanding.

You enjoy mentoring and supporting other engineers through coaching, knowledge sharing, and technical guidance.

You are comfortable working with agile delivery tooling such as Jira and Confluence, and understand the value of lightweight estimation, effort tracking, and documentation to support transparency and continuous improvement.

You actively and confidently use modern AI-assisted development tools as part of your day-to-day workflow, applying strong engineering judgement when doing so.

Knowledge, Skills & Experience

Core Engineering

• Strong experience delivering production software in a modern engineering environment

• Comfortable working in agile, cross-functional teams with iterative delivery

• Strong API-first mindset, including designing, versioning, documenting, and maintaining internal and external APIs

• Proven ability to architect solutions, translating requirements into secure, resilient, and scalable systems

• Strong experience with Go, including building and maintaining backend services (or clear evidence of rapid ramp-up)

• Solid understanding of cloud-native and serverless architectures

Cloud & Platform

• Hands-on experience with AWS, including Lambda, SQS, SNS, Step Functions, DynamoDB, and RDS (MySQL)

• Infrastructure as Code using Terraform

• CI/CD experience using GitHub Actions or equivalent tooling

• Strong observability mindset, including logs, metrics, traces, dashboards, and alerting

Frontend & Testing

• Frontend experience with TypeScript and Vue, or equivalent modern SPA frameworks

• Automated testing experience across unit, integration, and end-to-end levels (e.g. Playwright)

• Performance and load testing experience (e.g. k6)

Modern Development Practices & AI

• Demonstrable experience using modern development environments such as Visual Studio Code and JetBrains IDEs (e.g. GoLand, PyCharm), including effective use of debugging, refactoring tools, and extensions/plugins

• Confident using GenAI development assistants such as GitHub Copilot, ChatGPT, Claude, or similar, integrated into the development workflow

• Able to use AI tools responsibly to accelerate development, learning, test creation, documentation, and design exploration

• Strong judgement in validating AI-generated output to ensure correctness, security, performance, and maintainability

• Experience contributing to, or integrating, AI-driven features or services is desirable

Collaboration & Leadership

• Proven experience mentoring engineers through coaching, technical guidance, and knowledge sharing

• Strong written and verbal communication skills

• Experience working effectively with Product, UX, Test Automation, and DevOps teams, Experience modernising legacy PHP applications using incremental refactoring or strangler patterns

• Working knowledge of Python , particularly for data processing, automation, or AI-related workloads

• Experience integrating with external BI tools and data ecosystems

• Hands-on experience with AuthN/AuthZ providers (OIDC, OAuth2, SAML)

• Experience building with AWS Bedrock or similar managed AI platforms

• 4.5 day working week (Half day every Friday- 1pm finish)

• 25 days holiday (with the option to buy up to an additional 5 days per year)

• Private single medical insurance

• Employee Assistance Programme

• Life Assurance (4x Salary)

• Enhanced Maternity and Paternity Pay

• Tech Scheme Loan (of up to £2,000 per year)

• Ride to Work Scheme

• Season Ticket Loan

• Dedicated annual company and team social budget

We are building the next generation of call intelligence and AI-driven insight platforms. Over the next three years, our focus is on evolving from a strong analytics foundation into an outcome-driven, API-first platform that embeds intelligence directly into customer workflows. This is an opportunity to join us at a pivotal stage. You'll help shape both how we build and what we build, working on systems that process high-volume, high-value data and increasingly leverage AI and automation to deliver measurable customer and business outcomes. We value pragmatic engineering, clear thinking, and continuous learning. Our teams are small, autonomous, and outcome-focused, with a strong emphasis on quality, ownership, and collaboration., At infinity, our aim is to be the best call tracking provider in the world and to do that we welcome our employees with open arms and create an environment where you can bring your best self, every day! We're an equal opportunities employer. That means we'll never discriminate based on race, religion, origin, gender expression, sexual orientation, age, marital status, social economics status or disability status. In fact, our recruitment process is completely anonymised, and we don't see any of your personal details when we review your application. At Infinity, we don't treat our hiring process as a box ticking exercise and we're just as interested in team fit as we are technical fit. So, even if you don't meet all the requirements listed in one of our vacancies, get in touch with us anyway because we'd love to hear from you