shrb so it seems : sudo ls /boot/EFI/nixos                                                                                                                                                                                                                                   
2m2kzz1gn2l5dmp55nmjb2hywrl02gl4-linux-4.13.9-bzImage.efi  8i1sk0wbwliz0rrpmcq19nm1xlyjn6zg-linux-4.9.52-bzImage.efi  hyih8pbsri59ggrv3mcs7hqpn2gwvsbj-initrd-initrd.efi  qmvf53mgkyvblj065si0kmsk28bim2md-linux-4.13.7-bzImage.efi
378vc215zm6fyy9wh95jnhcv0jlm00gy-initrd-initrd.efi	   9q59l4zwsxjb7nzcmpqn7agv73kah9ii-linux-4.13.4-bzImage.efi  l6mv69bbnq3jfq7zdch8fvpqj9qpsh5n-initrd-initrd.efi  rfj9wqmjvc5wv7hx8p6a8mkgnv5q0zq5-initrd-initrd.efi
77g999nhiq4hygfvj7sp6h6f7q79q8qx-linux-4.13.5-bzImage.efi  9v5xw0il6cis0wwpbd1k26rb52ylc69p-linux-4.13.8-bzImage.efi  m8yvam9bc0nb8az1q2xnavpsbrz3awkj-initrd-initrd.efi  vi0xf012pgvwk2ryd7amxasdqfskb86c-linux-4.13.5-bzImage.efi
7glhad97h4v90wfvd77ix23wsjb3gr9i-linux-4.13.4-bzImage.efi  g6rhwj3h5lsxw6ydgd1k3bmismi4vx3f-initrd-initrd.efi	      nz8csflgqjpr20pdrxnqfalm1s4pibka-initrd-initrd.efi  yphlii3aqz08mvab752pxcnhm9fg0205-initrd-initrd.efi