signswith

Signwith is a term used in software development to describe an operation that produces a cryptographic signature for a data payload and attaches the signature with the payload for transmission or storage. The term is not a formal standard, but it appears as API naming in multiple libraries where a signing step is combined with subsequent data handling.

In typical usage, a function or method named signWith (or SignWith) accepts a signer (private key or signing object), the data to be signed, and optional parameters such as the hashing or signature algorithm. It returns a signed object that usually includes the original data, a signature value, and often a signer identifier or public key. Verification is performed using the corresponding public key and the chosen algorithm.

Applications include ensuring data integrity and authenticity in network messages, API requests, and blockchain transactions. Signwith patterns are commonly implemented alongside standards such as JSON Web Signatures (JWS) or CMS, enabling interoperable verification when the signed payload is transmitted between parties.

Security considerations include safeguarding private keys, choosing strong, industry-standard algorithms, including timestamps or nonces to prevent replay attacks, and ensuring canonical data representation to avoid signature mismatches across systems.

Historically, signWith-like APIs emerged from the need to simplify signing workflows in distributed systems, combining signing and transport steps into a single operation. See also digital signature, JWS, public-key cryptography.