Software Supply Chain Security and SBOMs
Securing everything you didn't write — from finding known-vulnerable dependencies with SCA, to generating an SBOM you actually act on, to proving provenance with signatures and SLSA so you know and verify what you ship.
Securing everything you didn't write: SCA for known-vulnerable dependencies, the supply-chain threat model (typosquatting, dependency confusion, build compromise), SBOMs (SPDX/CycloneDX), and provenance/integrity with SLSA and Sigstore signing.