Developed a Signer API for the 0xPARC/parcnet repository, focusing on secure and scalable private key handling for POD creation. The work centered on designing a Signer struct in Go, encapsulating private key parsing, decoding, and signing operations to centralize and streamline key management. Enhanced validation for private key formats was implemented to improve input correctness and overall security. By reducing redundant key operations and centralizing logic, the solution enabled more robust and scalable mass POD creation workflows. The project leveraged skills in API design, backend development, and cryptography, emphasizing maintainability and security in backend systems for cryptographic operations.