I encountered this error while trying to rebuild nixos. What is the cause? 
```
Failed assertions:
- CONFIG_DEVTMPFS is not enabled!
- CONFIG_CGROUPS is not enabled!
- CONFIG_INOTIFY_USER is not enabled!
- CONFIG_SIGNALFD is not enabled!
- CONFIG_TIMERFD is not enabled!
- CONFIG_EPOLL is not enabled!
- CONFIG_NET is not enabled!
- CONFIG_SYSFS is not enabled!
- CONFIG_PROC_FS is not enabled!
- CONFIG_FHANDLE is not enabled!
- CONFIG_CRYPTO_USER_API_HASH is not enabled!
- CONFIG_CRYPTO_HMAC is not enabled!
- CONFIG_CRYPTO_SHA256 is not enabled!
- CONFIG_DMIID is not enabled!
- CONFIG_AUTOFS4_FS is not enabled!
- CONFIG_TMPFS_POSIX_ACL is not enabled!
- CONFIG_TMPFS_XATTR is not enabled!
- CONFIG_SECCOMP is not enabled!
- CONFIG_TMPFS is not yes!
- CONFIG_BLK_DEV_INITRD is not yes!
- CONFIG_BINFMT_ELF is not yes!
- CONFIG_UNIX is not enabled!
- CONFIG_INOTIFY_USER is not yes!
- CONFIG_NET is not yes!
- You must now pre-generate the host keys for initrd SSH.
See the boot.inird.network.ssh.hostKeys documentation
for instructions.
```