**Source URL:** https://limited.veevavault.dev/qualityone/vault-sdk/shared-code.md

# Shared Code

<LandingPageList>

* [Request Context](/qualityone/vault-sdk/shared-code/request-context/)
* [User-Defined Classes](/qualityone/vault-sdk/shared-code/udc/)
* [User-Defined Models](/qualityone/vault-sdk/shared-code/udm/)
* [User-Defined Services](/qualityone/vault-sdk/shared-code/uds/)

</LandingPageList>

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