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arXiv · 2603.22587

flexvec: SQL Vector Retrieval with Programmatic Embedding Modulation

Damian Delmas
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Abstract

As AI agents become the primary consumers of retrieval APIs, there is an opportunity to expose more of the retrieval pipeline to the caller. flexvec is a retrieval kernel that exposes the embedding matrix and score array as a programmable surface, allowing arithmetic operations on both before selection. We refer to composing operations on this surface at query time as Programmatic Embedding Modulation (PEM). This paper describes a set of such operations and integrates them into a SQL interface via a query materializer that facilitates composable query primitives. On a production corpus of 240,000 chunks, three composed modulations execute in 19 ms end-to-end on a desktop CPU without approximate indexing. At one million chunks, the same operations execute in 82 ms.

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Damian Delmas. 2026-03-23. flexvec: SQL Vector Retrieval with Programmatic Embedding Modulation. https://arxiv.org/abs/2603.22587

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