Lead Software Engineer - Performance at Deputy

Deputy is a global SaaS remote-first workforce management company with hubs in Sydney, Melbourne, San Francisco and London, plus team members working remotely across the United States. Our platform serves over 1.5 million workers and 375,000 workplaces across 100+ countries. We are backed by top global investors and recently achieved Unicorn status.  At Deputy, we’re improving the world of work, one shift at a time, for 80% of the world’s workforce: hourly workers. These are the dedicated employees who keep our world running – from baristas to nurses, cleaners to delivery drivers, florists to factory workers. Despite their vital role in society, most workplace technology has focused on those workers who sit behind a desk, but at Deputy, we transform the frontline. When businesses use Deputy, their workplaces thrive – the business is more profitable, compliant, and productive, while the workers are more engaged and happier at work. We're becoming an AI-native company, a commitment that means you'll be empowered (and expected) to use AI tools and thinking in your day-to-day work. You'll have the training, support, and freedom to use AI responsibly and creatively to spark ideas, solve problems faster, and unlock new ways of working. If you’re passionate about creating solutions that put people first and helping businesses and their teams thrive, join us at Deputy and make an impact where it matters most! The Role As a backend Software Engineer - Performance, you are a senior individual contributor responsible for owning and driving the performance, scalability, and cost efficiency of Deputy’s core Workforce Management platform.This role is highly specialised and hands-on. You will work across core Workforce Management domains — Scheduling, Timesheets, Leave, and Compliance — identifying performance bottlenecks, legacy constraints, and architectural inefficiencies, then leading initiatives end-to-end to address them. You will operate with a high degree of autonomy, forming and leading performance-focused initiatives that often run without direct product direction. You will define the problem, shape the technical approach, break work into deliverable milestones, and drive execution through collaboration and influence rather than line management. Your work will directly impact mid-market and enterprise customers operating at scale, supporting high-volume workloads across multiple regions and time zones, and ensuring the platform continues to perform reliably as data volumes, customer complexity, and usage grow. Responsibilities Platform Performance Ownership • Own and continuously improve the performance posture of the Workforce Management platform across core domains, with a focus on API latency, page load times, and infrastructure cost efficiency. • Proactively identify performance risks and bottlenecks across legacy and modern systems, addressing issues before they impact customers. • Lead initiatives to modernise and simplify legacy customisations and workflows that negatively impact performance, reliability, or operational cost. Hands-on Technical Leadership • Design, implement, and deliver performance-focused improvements across backend services, APIs, data stores, and search infrastructure. • Perform deep analysis of SQL queries, database access patterns, and data models, driving query optimisation, indexing strategies, and data access improvements. • Design and implement effective caching strategies (application-level, data-store, and API-level), balancing performance gains with correctness and consistency. • Work extensively with OpenSearch at scale, optimising indexing, query performance, ingestion pipelines, and cost efficiency for systems ingesting millions of new records each week. Legacy Modernisation & Migration • Work hands-on with legacy codebases, including long-lived PHP systems, identifying opportunities to improve performance, reliability, and maintainability. • Lead and contribute to incremental migration strategies that transition performance-critical paths from legacy systems to modern solutions (e.g. Go-based services), without disrupting customer workflows. • Balance short-term performance improvements with longer-term platform modernisation, ensuring changes are safe, observable, and reversible. Multi-Tenant & Enterprise Scale • Design and implement performance solutions that operate effectively in multi-tenant environments, maintaining isolation, fairness, and predictability across customers. • Optimise systems that handle high concurrency, large data volumes, and enterprise usage patterns across multiple regions and time zones. Initiative Leadership & Influence • Define and own performance initiatives end-to-end, from problem discovery and technical design through to delivery and validation. • Break complex problems into clear milestones and delegated tasks, collaborating with engineers across squads to drive outcomes. • Set and uplift platform performance standards, tooling, and ways of working in partnership with Infrastructure, Quality, and Product Engineering teams. • Mentor and guide other engineers in performance-oriented thinking, debugging techniques, and system design, leading by example through hands-on contribution. Skills & Experience Core Experience • 6+ years of professional software development experience, including operating production systems at scale. • Hands-on experience across multiple Workforce Management domains, such as Scheduling, Rostering, Timesheets, Leave, and Compliance, will be highly regarded. • Product and domain understanding of Workforce Management, including the operational and compliance complexity faced by mid-market and enterprise customers, will be highly regarded. Performance, Data & Systems • Proven experience leading and delivering performance optimisation initiatives across complex systems. • Strong expertise in SQL query optimisation, including execution plans, indexing strategies, and tuning for high-volume workloads. • Extensive experience designing and operating caching strategies, including cache invalidation and consistency trade-offs. • Hands-on experience with OpenSearch at scale, including index design, query optimisation, ingestion pipelines, and cost/performance trade-offs. Architecture & Modernisation • Proven experience working with legacy systems and modern platforms, including planning and executing migrations from legacy architectures to modern solutions. • Experience evolving performance-critical paths from monolithic or tightly coupled systems into more maintainable, scalable implementations. • Strong backend engineering skills, with experience in PHP and Go highly advantageous. • Experience designing and operating APIs (REST, RPC) and distributed systems using modern cloud infrastructure and tooling. Technical Leadership • Comfortable operating as a senior individual contributor with broad influence and ownership, without direct reports. • Ability to lead through technical credibility, collaboration, and pragmatic decision-making. • Strong communication skills, able to explain complex performance and architectural trade-offs to both technical and non-technical stakeholders. • A pragmatic problem solver with a strong bias toward measurable improvement, system health, and continuous learning. Employee Perks - Enjoy a flexible remote-first work policy (with a work-from-home stipend to set you up for success!) - Own A piece of Deputy via our Employee Share Ownership Plan (ESOP)  - Take paid parental leave to support you and your family  - Stay protected with Group Salary Continuance Insurance - Access support through our Employee Assistance Program - Enjoy additional leave days — including study assistance, celebration days and volunteering - Join our global working groups focused on collaboration, belonging and connection - Get creative at our annual Hackathons - Take advantage of our novated leasing for electric vehicles, internet reimbursement and more! Learn more about our Design, Engineering & Product teams here Deputy believes in equal opportunity and that inclusiveness and diversity promotes innovation. Our global team members are from a variety of cultures. And we welcome different perspective and skills.  #LI-Hybrid