Staff Software Engineer - AI Search
Date: Oct 22, 2025
Location: London, GB, WC2N 4JS
Company: Optimizely
At Optimizely, we're on a mission to help people unlock their digital potential. We do that by reinventing how marketing and product teams work to create and optimize digital experiences across all channels. With Optimizely One, our industry-first operating system for marketers, we offer teams flexibility and choice to build their stack their way with our fully SaaS, fully decoupled, and highly composable solution.
We are proud to help more than 10,000 businesses, including H&M, PayPal, Zoom, and Toyota, enrich their customer lifetime value, increase revenue and grow their brands. Our innovation and excellence have earned us numerous recognitions as a leader by industry analysts such as Gartner, Forrester, and IDC, reinforcing our role as a trailblazer in MarTech.
At our core, we believe work is about more than just numbers -- it's about the people. Our culture is dynamic and constantly evolving, shaped by every employee, their actions and their stories. With over 1500 Optimizers spread across 12 global locations, our diverse team embodies the "One Optimizely" spirit, emphasizing collaboration and continuous improvement, while fostering a culture where every voice is heard and valued.
Join us and become part of a company that's empowering people to unlock their digital potential!
To get a sneak peek into our culture, find us on Instagram: @optimizely
Introduction
We're seeking a skilled Staff Software Engineer with leadership ambition, to join our Graph team. This role requires significant experience designing, implementing, and maintaining SaaS with high traffic load. This role requires several years of experience building semantic search, agentic search, and multilingual search systems. You will own epics from initial requirements gathering (PRD) through to successful completion, collaborating with stakeholders to ensure solutions meet market needs. You will also focus on the request latency when implementing features, to make sure our customers’ applications have good performance.
As a Staff Software Engineer, You Will...
- Lead development and optimization of semantic search using LLMs, with a strong focus on multilingual support and improving non-English language performance.
- Systematically track, document, and address language-specific differences and rules for search relevance and query understanding.
- Architect and implement agentic search capabilities, leveraging AI/LLM technologies to deliver context-aware, personalized, and conversational search experiences.
- Design and enhance translation layers from GraphQL to Opensearch queries, ensuring accuracy, efficiency, and scalability.
- Mentor and support engineers and customers in building effective, performant search queries and solutions.
- Collaborate cross-functionally to define and deliver advanced search features, including AI-driven ranking, intent detection, and query rewriting.
Why is this team critical to Optimizely?
- Business Impact: Optimizely Graph is the core content delivery and search service powering the SaaS version of our Content Management System (CMS). Our customers, who rely on Graph for their websites and mobile applications, demand high performance and advanced query capabilities to deliver exceptional user experiences. Graph's reliability and speed directly impact their business success.
- High Visibility & Innovation: Our roadmap prioritizes innovative content delivery and search features, placing search and AI at the forefront of our service offering. This focus differentiates us from competitors and empowers our customers to build cutting-edge web and mobile applications. You'll be instrumental in developing these differentiating features.
- Shape the Future of Digital Experiences: The team plays a critical role in shaping the future of our customers' digital presence. Your contributions will directly influence how they engage their audiences and achieve their business objectives through innovative search and content delivery experiences.
About You
- You have deep expertise in search technologies such as Opensearch (preferred), Elasticsearch, or Solr as well as modern AI/LLM frameworks (OpenAI, HuggingFace, etc.).
- You have proven experience building semantic search and agentic search systems in production environments.
- You have a strong background in natural language processing (NLP), multilingual search, and cross-lingual relevance tuning.
- You have hands-on experience with query translation, query optimization, and search analytics.
- You have demonstrated your ability to work directly with customers and stakeholders to understand requirements and deliver tailored solutions.
- You have excellent communication and technical leadership skills with the ability to mentor and influence across teams.
- You have a track record of driving innovation in search, AI, and LLM-powered products.
- Ideally, you also have experience with search evaluation, A/B testing, and relevancy measurement.
Some Technologies We Work With..
- TypeScript, JavaScript, C#
- GraphQL, REST
- Cloudflare workers, Kubernetes
- OpenSearch
Education
Bachelor’s Degree (Computer Science or engineering preferred) or equivalent work experience
Optimizely is committed to a diverse and inclusive workplace. Optimizely is an equal opportunity employer and does not discriminate on the basis of race, national origin, gender, gender identity, sexual orientation, protected veteran status, disability, age, or other legally protected status.
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