Join HL and be part of the team, building software for the UK's largest investment platform. Hargreaves Lansdown (HL) - the UK's number one platform for private investors, trusted by 1.9 million clients with over £155 billion in savings and investments. For over 40 years, HL has been helping people save and invest for a better future, earning over 200 industry awards, including Best Investment App and Best for Customer Service in 2024. Our solutions are used daily by millions of clients, helping to power the operations of a leading financial institution. Our culture is built on innovation, knowledge sharing, and continuous improvement-and we're looking for talented engineers to join a team developing web (and mobile) products using PHP, TypeScript and AWS. We are looking for a Senior Software Engineer to help support our dedicated, friendly and growing Trading Team to deliver critical new functionality to our clients and internal users. If you enjoy working with clean architecture, modern technologies, and being part of a supportive team that learns from each other, we'd love to hear from you! As a Senior Software Engineer at HL, you'll be joining the development team responsible for HL's online trading platform; the services that power our award-winning mobile applications as well as several other important internal and external web-based systems. HL has big plans for the future; we want to be at the forefront of client service and experience offered through digital channels. Our online platform and its capabilities are the foundation of this journey and have played a key part in our success to date. While the Linux/Apache/MariaDB/PHP (LAMP) stack is currently what primarily drives our web applications, we are a multi-disciplinary group, transitioning to use various new technologies as part of our digital transformation (Typescript & AWS). You will be working on anything from a small text change on the front-end through to a set of internally or externally facing APIs to support new functionality required across our different platforms. Within this role, you'll be working closely with a skilled and passionate cross-functional team to deliver improvements and crucial changes to our services in an agile way. You will have the opportunity to be instrumental in shaping and delivering large scale systems projects. Therefore, the ability to develop modern, scalable, secure, high performant applications is imperative. You should also embrace a culture that focuses on teamwork, rapid learning, and the continuous delivery of valuable software. The ability to collaborate, prioritise team goals over individual goals, maintain a focus on priority tasks and deliver on commitments is essential. Key Duties and Responsibilities Writing high quality code adhering to agreed team and regulatory standards, and the review of others code. Working collaboratively with the team to help deliver significant new features for the business. Providing engineering support for existing applications when necessary. To ensure existing and newly developed solutions are reliable, secure, performant and maintainable. Maintaining awareness of current secure coding practices and ensure code produced is in line with these. Developing and evidencing automated tests alongside code produced. Documenting all solutions produced, to agreed team standards. Demonstrating a willingness to learn and further technologies & techniques embraced by development team. Cultivating strong working relationships both within working squad and the wider business. Essential Skills Proficient knowledge and understanding of PHP, particularly when developing within a Linux/Apache/MariaDB/PHP stack. Ability to effectively use HTML, CSS, JavaScript, with an understanding of browser support & standards, W3C compliance. Understanding of object-oriented programming (OOP) model principles. Understanding of web application design patterns. Understanding of common web application security vulnerabilities and appropriate mitigations. Understanding of PHP frameworks - particularly Symfony. Knowledge of PHP templating engines, in particular, Smarty and Twig. Have a practical appreciation of database design and working practices. Principles of RESTful API development, including structuring, documenting, versioning, testing and stubbing/mocking. Experience developing scalable, secure, high performant, database driven web applications. Experience developing automated unit tests alongside code, e.g. with PHPUnit, Playwright. Knowledge and experience interfacing with Oracle, Apache Solr. Experience in working with automation, Continuous Integration and Delivery pipelines. E.g. GitLab Third party API services integration experience. Knowledge of Typescript & React Framework. (Nice to have) Experience working with any of Docker, Kubernetes, AWS.