# Work

> Each record states the problem, the approach, and the conclusion.

- [Public search at country scale](https://oppority.com/work/public-search.md): Search a citizen can use: a polling place, a beneficiary record, found in hundreds of millions of rows. Subjects: Enterprise search, Apache Solr.
- [Concept search before vectors were the default](https://oppority.com/work/concept-search.md): A books-and-journals search that let people explore by concepts, built in 2018 from phrases and similarity, not from a vector database. Subjects: Apache Solr, Relevance, Hybrid search.
- [One catalog, many storefronts](https://oppority.com/work/retail-search.md): E-commerce search for one catalog across a website, a marketplace, and stores: product search, autosuggest, filters, and per-field similarity. Subjects: Relevance, Apache Solr, Enterprise search.
- [Recommendations in the result, and beside it](https://oppority.com/work/related-results.md): Recommendations served by the search engine in two places: inside the result list, and alongside it. Subjects: Relevance, Enterprise search.
- [Return one record, not a list](https://oppority.com/work/one-best-record.md): High-precision identification: from millions of candidates that share an organisation's name and address, return the single best record. Subjects: Relevance, Enterprise search.
- [A move that kept the answers](https://oppority.com/work/platform-move.md): A production move from self-managed Apache Solr to managed OpenSearch, checked by whether the top results still agreed. Subjects: Apache Solr, OpenSearch, Relevance, Enterprise search.
- [The team's output](https://oppority.com/work/search-team.md): Leading a search engineering group while staying close enough to the system to tell a relevance question from an operations question. Subjects: Engineering management, Enterprise search, Apache Solr.
- [A new engine, tried on a laptop](https://oppority.com/work/reading-luxir.md): A hands-on reading of Luxir, a new hybrid search engine, run from a Mac or Windows laptop without compiling C++. Subjects: Luxir, Hybrid search, Guides.