With the sunsetting of JFrog GoCenter, Go modules have become the standard package manager in Golang, automatically enabled with a default GOPROXY upon installation. A GOPROXY serves as a repository to control the source of Go module downloads, ensuring builds are deterministic and secure by caching module versions to maintain immutability and availability. Developers can use public GOPROXYs like proxy.golang.org for open-source modules, while the GOPRIVATE environment variable allows for the secure retrieval of private modules directly from VCS repositories without exposing them through public networks. Alternatively, private GOPROXYs can be installed to store both public and private modules on local infrastructure, ensuring immutability and availability while preventing sensitive information from being leaked. Tools like JFrog Artifactory support these setups and can be deployed on-premise, in the cloud, or as a SaaS solution, accommodating multiple languages and package managers to promote a stable and secure software development process.