The deluge of digital biodiversity datasets unleashed through institutional, national and global infrastructures brings up an inconvenient truth: internet-connected infrastructures are in a constant state of flux while preservation and integration of digital knowledge are often afterthoughts. Rather than taking digital amnesia for granted, we examine examples of durable and frugal digital data preservation and integration methods. Examples include tracking external datasets, creating verifiable data citations, cross-publishing and cross-linking datasets, reproducing data-integration processes, and distributing large data archives across poor, or nonexistent, internet connections. Topics include cryptographic hashes, Provenance Ontology, content-addressed storage, Unix philosophy, and offline first design as applied in projects like Preston (https://preston.guoda.bio) and Global Biotic Interactions (https://globalbioticinteractions.org). The examples are then related to best practices applied by proven knowledge-preservation experts: librarians and curators.