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arXiv · 2604.06273

CobbleDB: Modelling Levelled Storage by Composition

Emilie Ma·Ayush Pandey·Annette Bieniusa·Marc Shapiro
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Abstract

We present a composition-based approach to building correctby-construction database backing stores. In previous work, we specified the behaviour of several store variants and proved their correctness and equivalence. Here, we derive a Java implementation: the simplicity of the specification makes manual construction straightforward. We leverage spec-guaranteed store equivalence to compose performance features, then demonstrate practical value with CobbleDB, a reimplementation of RocksDB's levelled storage.

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Emilie Ma, Ayush Pandey, Annette Bieniusa, Marc Shapiro. 2026-04-07. CobbleDB: Modelling Levelled Storage by Composition. https://arxiv.org/abs/2604.06273

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