APIs, OAI-PMH and a triplestore.
HAL uses many identifiers to facilitate interoperability. The DOI or other document identifiers make it possible to extract metadata during deposit, to link the deposit to the document available on another platform and/or to link the publication to research data archived in a repository.
The identifiers managed are aligned with other repositories: they concern authors such as ORCID, their affiliations such as ROR, or even funding (ANR, European projects).
See also Identifiers used in HAL
HAL has been a partner of arXiv since its beginning, and is a trusted third party (see Third Party submission): the depositor can request that their deposit be transferred to arXiv, provided they comply with the platform's terms and conditions. Once the deposit is published online on HAL, it is transferred to arXiv. The deposit is then be moderated by arXiv. In accordance with arXiv's recommendations, this transfer channel is reserved for authors affiliated to a French institution only.
For software source code, HAL transfers the files to Software Heritage. The HAL deposit is updated with the SWHID identifier and allows the source code to be cited.
HAL is compatible with Episciences, a platform which is also developed by the CCSD. An author wishing to submit a preprint to a journal distributed on the platform can deposit it in HAL. Once accepted and published by the journal, the corresponding HAL deposit is automatically updated with publication metadata.
Deposits with a PubMed ID (PMID) and an author's version (preprint/postprint) without embargo are displayed in PubMed (HAL logo or LinkOut section. They are also displayed on Europe Pubmed Central. To search the relevant deposits via the advanced search form, select HAL open archive in the external links list.
Deposits in Economics are displayed on RePec (see Archives participating in RePEc).
HAL is harvested by OpenAIRE. OpenAIRE compatibility: OpenAIRE 3.0 (OA, funding)
HAL is also harvested by Unpaywall, an open database of free scholarly articles.
See also the list of platforms using HAL as a data source