Backend Engineer (Search & Relevance) İş İlanı

🔎 Senior Backend Engineer – Search Relevance & Information Retrieval About Cressoft Cressoft is a UK-based IT consultancy, operating since 2011 and delivering elite technical talent to global brands. We support large-scale digital transformation programmes across software engineering, cloud, data, AI, and digital commerce. About the Role We’re looking for an experienced Search Engineer to join a large-scale digital platform project. This is a specialist search engineering role . We’re looking for engineers with genuine hands-on experience in search relevance, ranking, retrieval, tuning, and search evaluation rather than candidates whose experience is primarily general AI or Machine Learning. Candidates may come from Search Engineering, Backend Engineering, Data, or ML backgrounds , but you must be able to demonstrate substantial hands-on experience building and improving search systems. 🛠 Key Responsibilities Build, optimise, and improve large-scale search and retrieval systems Improve search relevance and ranking quality Develop and tune ranking and retrieval algorithms Perform query optimisation and relevance tuning Define and implement approaches for search quality evaluation Work with techniques such as BM25 and Learning to Rank (LTR) Build solutions using Elasticsearch, OpenSearch, Solr, or Lucene Contribute to semantic, vector, and hybrid search capabilities while maintaining strong traditional Information Retrieval fundamentals Develop search-related services and tooling using Java or Python Collaborate with engineering, product, data, and ML teams to continuously improve the search experience ✅ Key Requirements Strong Information Retrieval (IR) fundamentals Hands-on search relevance and relevance tuning experience Experience with search ranking / ranking algorithms Strong understanding of retrieval and query optimisation Experience with search quality and evaluation Knowledge of Learning to Rank (LTR) and/or BM25 Hands-on experience with at least one of: Elasticsearch OpenSearch Solr Lucene Experience with semantic, vector, or hybrid search , supported by strong search fundamentals Strong programming experience with Java or Python Substantial commercial experience working directly with search systems 🎯 What We’re NOT Looking For This is not a general AI/ML Engineer role . AI/ML experience can be valuable, but candidates must have genuine hands-on experience with Information Retrieval, relevance, ranking, retrieval optimisation, and search evaluation . 🔗 Click and help shape the next-generation retail platform from wherever you are in Turkey.