Senior Core Technologies Engineer

Fin , now part of Salesforce, is on a mission to help businesses provide perfect customer experiences. Our AI Agent Fin is the highest-performing AI Customer Agent on the market today, enabling businesses to deliver impeccable, always-on customer support across the customer journey, from service, to sales, to ecommerce. Powered by our own AI models, Fin resolves complex customer issues end-to-end across every channel, with minimal set-up and integration. Fin can also be combined with our natively integrated Intercom help desk, giving modern support teams one single system. Together with Salesforce, the #1 AI CRM, where humans with agents drive customer success, we're building the future of customer experience. Here, ambition meets action. Tech meets trust. And innovation isn't a buzzword, it's a way of life. The world of work as we know it is changing, and we're looking for Trailblazers who are passionate about bettering business and the world through AI. Ready to level up your career at the company leading workforce transformation in the agentic era? You're in the right place. Agentforce is the future of AI, and you are the future of Salesforce. What’s the opportunity? We are looking for a Senior Engineer to join the team that enables the core technologies that Fin is built on . This role is especially compelling for engineers who enjoy scaling Elasticsearch in production and who also like working across adjacent systems such as MySQL, ingestion pipelines, and owning how they operate from low level systems engineering to all parts of our Rails and monolith. Our team’s mission is to accelerate Fin’s growth and stability through educated and operationally excellent core technology usage. This means that we’re here to help product engineers and ML scientists build simpler, more performant product - faster. This can be through things like making low level database improvements that enhance everyone's experience, building best in class Elasticsearch tooling, or partnering with teams that utilise any of Fin’s core technologies or our build patterns. Previous projects from the team include future-proofing our databases through sharding and building a mechanism to migrate Elasticsearch indexes for scale and profit . We’re building a robust platform where your expertise will be applied to areas such as building a beautiful Messenger, an efficient teammate experience, a secure by default system, all while scaling the platform to billions of users and shipping two hundred new versions of Intercom to production every day. Delve deeper into our engineering culture at Fin.engineering and explore our engineering values . What will I be doing? Own high-impact work on Elasticsearch at scale, including index design, shard and partitioning strategy, cluster health, performance tuning, safe migrations, and operational excellence. Collaborate with world-class domain experts to shape our technical direction and infrastructure as we grow. Deeply own aspects of our infrastructure at Fin and autonomously executing on high impact projects - including writing application code, automating systems, improving observability and low-level tuning of datastores used in production, test and development across Fin. Value agility and simplicity, just as you prioritise scalability and uptime. Our continuous deployment approach ensures focus on gradual improvements. Major accomplishments are introduced incrementally, staying under the radar with feature flags. Contribute to all phases of software development including ideation, prototyping, design and implementation. This role has a mix of both hands-on development as well as strategic work and enablement. Play an active role in the hiring, mentoring, and career development of other engineers. Raise the bar for technical standards, performance, reliability, and operational excellence across Fin. What skills do I need? Excellent pragmatic engineering skills. 5+ years experience in a production environment, with contributions to the design and architecture of distributed systems. Strong experience with at least one major production datastore or search system, with Elasticsearch being especially relevant for this role. Good judgment around Elasticsearch in real-world systems, such as index and mapping design, cluster operations, scaling patterns, performance tuning, or migrations. Expertise in backend technologies such as MySQL, Memcached, as well as Linux. Ideally, you’ve supported scaling a SaaS product i