asterisc-release/saguaro is a Linux-compatible library operating system derived from Gramine, aiming to run unmodified Linux applications in isolated environments. The repository presents itself as a project for sandbox and confidential workloads, and there is no publicly released latest release. So this post is not about a newly announced version or its changes, but a look at the project itself as described by the repository.
The project says it offers several execution layers, including direct execution and virtual machines, as well as SGX, TDX, SEV and VBS. Its architecture covers not only the x86 family but also AArch64 and RISC-V. Graphics acceleration, multiprocess, signal handling and networking are listed as supported items as well. Covering multiple execution environments and architectures is the core of this repository. Here a library operating system refers to a structure that provides operating system features so that applications run in isolated environments.
That said, the repository explicitly states that it is currently experimental and should not be used in production environments. In the support matrix, some combinations of execution environments and architectures are still experimental or planned. Therefore it is hard to assume that the listed features are equally available in every combination. The judgment supported by the current material stops at this being an early-stage project that targets multiple execution layers.