Template.with_kernel(...), so kernel choice is an environment lane,
not a per-template SDK method.
Current lanes
For private beta, use a deployment lane whose host kernel and rootfs are both
FUSE-capable when you need shared volumes or bucket mounts. Until an explicit
SDK selector ships, do not document or call
Template.with_kernel(...).
Kernel version
The default local download lane uses Firecracker1.14.1 and attempts the
Firecracker Linux 5.10 guest kernel artifact for the host architecture. The FUSE
builder pins NULLSPACE_FUSE_LINUX_VERSION=5.10.252 unless overridden.
Check the actual running guest when exact version matters: