Senior Software Engineer

About the Technology Organization 

Technology at Lilly builds and maintains capabilities using pioneering technologies like most prominent tech companies. What differentiates Technology at Lilly is that we create new possibilities through tech to advance our purpose – creating medicines that make life better for people around the world, like data driven drug discovery and connected clinical trials. We hire the best technology professionals from a variety of backgrounds, so they can bring an assortment of knowledge, skills, and diverse thinking to deliver solutions in every area of our business. 

About the Business Function 

The Software Product Engineering (SPE) team is a specialised engineering group that delivers strategic solutions and differentiated capabilities. We take a forward-thinking approach, focusing on an enterprise platform and product mindset, ensuring that the solutions we build can be leveraged across Technology teams for broader impact and efficiency. 

Job Title: Senior Software Engineer  

Role Summary 

As a Senior Software Engineer – Full Stack, you will design, develop, and maintain scalable, high-performance applications across both frontend and backend systems. You will collaborate with cross-functional teams, mentor junior engineers, and drive technical excellence in cloud-native, secure, and maintainable solutions. Candidates should be strong in either frontend or backend but ideally possess full stack capabilities. 

What You’ll Be Doing 

• Develop and maintain scalable, high-performance server-side applications using Node.js and Express.js. 

• Build and maintain RESTful and GraphQL APIs to support frontend systems and external service integrations. 

• Integrate with PostgreSQL databases using ORM tools such as Sequelize and Knex.js. 

• Design and implement performant and reliable systems by applying appropriate caching strategies and integrating distributed components such as Redis, CDNs, and message queues. 

• Handle file uploads and processing using tools like Multer, ExcelJS, and CSV Parse. 

• Ensure secure authentication using frameworks such as Azure MSAL Node, JWT, and express-session. 

• Optimise backend services for scalability, performance, and security. 

• Develop and maintain scalable, high-quality frontend components using React, Material-UI, Emotion, and related libraries. 

• Build responsive, accessible, and performant user interfaces, ensuring cross-browser compatibility and adherence to accessibility standards (WCAG). 

• Collaborate with backend engineers to integrate RESTful/GraphQL APIs built with Node.js and Express.js. 

• Work with PostgreSQL databases via Sequelize or Knex.js, and implement client-side caching (e.g., IndexedDB, Redis). 

• Maintain and optimise build pipelines using Webpack, Babel, ESLint, Docker, and CI/CD tools (e.g., GitHub Actions, AWS CodeBuild). 

• Deploy and manage applications on cloud platforms (AWS ECS Fargate, S3, RDS, CloudFormation, etc.). 

• Take responsibility for authoring technical documents, including design documents, architecture specifications, code review records, and other relevant documentation to support engineering best practices and knowledge sharing. 

• Implement security best practices (Helmet, SSL/TLS, OAuth2/Azure MSAL) and monitor application health using AWS CloudWatch and Winston logging. 

• Participate in code reviews, advocate for engineering excellence, and contribute to the evolution of component libraries and design systems. 

• Analyse, debug, and refactor software to improve maintainability and performance. 

• Mentor junior engineers and collaborate cross-functionally with product, design, and engineering teams. 

• Leverage AI tools like GitHub Copilot to accelerate development workflows, improve code quality, and reduce boilerplate. 

• Encourage and mentor team members on responsible and secure use of AI in the software development lifecycle. 

How You Will Succeed 

• Demonstrate proven expertise in designing and implementing scalable backend architectures using microservices, serverless, and event-driven patterns, grounded in SOLID principles, design patterns, and clean code practices. 

• Apply strong system design principles to build modular, robust, and maintainable backend and frontend solutions that support long-term scalability and reliability. 

• Exhibit hands-on experience with security best practices and compliance in highly regulated environments. 

• Drive code review, refactoring, and continuous improvement of backend and frontend systems to ensure long-term maintainability and performance. 

• Build responsive, accessible, and performant user interfaces using React and related technologies. 

• Integrate with backend services using Node.js, Express.js, and RESTful/GraphQL APIs. 

• Ensure all backend solutions comply with healthcare regulations (e.g., HIPAA, GDPR) and Lilly’s internal compliance standards. 

• Maintain and optimise build pipelines and CI/CD workflows. 

• Mentor junior engineers and foster a culture of engineering excellence and continuous learning. 

• Communicate effectively and work collaboratively across backend, frontend, DevOps, and product teams. 

What You Should Bring 

• 5-8 years of professional software development experience, with proven expertise in either frontend or backend (full stack preferred). 

• Hands-on experience developing production-grade web applications with React, Material-UI, Emotion, and React Router. 

• Strong proficiency in JavaScript (ES6+), TypeScript, HTML5, CSS3, SCSS/Sass. 

• Experience with state management tools (Redux, Redux Toolkit, Context API). 

• Experience in backend development using Node.js and Express.js. 

• Strong understanding of API design (REST & GraphQL) and real-time data flow. 

• Proficiency in PostgreSQL and ORM tools (Sequelize, Knex.js). 

• Experience with cloud infrastructure (preferably AWS), CI/CD pipelines, and containerisation (Docker). 

• Familiarity with build tools (Webpack, Babel, ESLint, Vite) and modern frontend workflows. 

• Solid understanding of accessibility, performance optimisation, and Core Web Vitals. 

• Experience integrating with backend services using Node.js, Express.js, and RESTful/GraphQL APIs. 

• Working knowledge of PostgreSQL (Sequelize, Knex.js, pg-promise) and Redis for caching/session management. 

• Exposure to CI/CD pipelines, Docker, and cloud deployment (AWS preferred). 

• Experience with unit and integration testing (Jest, React Testing Library, Cypress, Playwright). 

• Understanding of authentication/authorisation (OAuth2, Azure MSAL, express-session) and security best practices. 

• Bachelor’s degree in computer science, Computer Engineering, or a related field. 

• Proven ability to self-drive and take ownership of technical initiatives. 

• Strong communication and collaboration skills across cross-functional teams. 

Preferred Skills 

• Experience with FeathersJS or similar frameworks. 

• Knowledge of accessibility best practices and WCAG standards. 

• Experience with design systems like Material-UI, Ant Design 

• Familiarity with Core Web Vitals and frontend performance optimisation techniques. 

• Hands-on experience with responsive design and cross-browser compatibility. 

• Experience with frontend testing tools such as Jest, React Testing Library, Cypress, or Playwright. 

• Familiarity with modern frontend build tools like Webpack, Vite, Babel, and ESLint. 

• Expertise with cloud platforms (preferably AWS is mandatory), including hands-on experience with containerisation technologies such as Docker and AWS ECS/ECR.  

• Having AWS and Kubernetes certifications is a significant advantage and will be highly valued for this role. 

• Experience with microservices architecture and API documentation (Swagger). 

• Experience integrating with third-party APIs (AWS SDK, SAP, Kaltura, On24, etc.). 

• Proficiency with AI-powered development tools (GitHub Copilot, prompt engineering). 

• Contribution to open-source projects or tech communities. 

• High level of intellectual curiosity and continuous learning mindset. 

• Ability to work independently and take ownership of technical solutions. 

• Solid understanding of Agile methodologies and SDLC. 

• Experience in regulated industries (e.g., Life Sciences) is a bonus but not required.