Apex domains cannot have CNAME records.
Question and response
Question
dig run. NS
Answer
run. 5 NS v0n1.nic.run.
run. 5 NS v2n1.nic.run.
run. 5 NS v0n3.nic.run.
run. 5 NS v2n0.nic.run.
run. 5 NS v0n0.nic.run.
run. 5 NS v0n2.nic.run.
Authority
The response has no authority records.
Additional
v0n0.nic.run. 156418 A 65.22.32.40
v0n1.nic.run. 156418 A 65.22.33.40
v0n2.nic.run. 156418 A 65.22.34.40
v0n3.nic.run. 156418 A 161.232.16.40
v2n0.nic.run. 162015 A 65.22.35.40
v2n1.nic.run. 156418 A 161.232.17.40
v0n0.nic.run. 156418 AAAA 2a01:8840:22:0:0:0:0:40
v0n1.nic.run. 156418 AAAA 2a01:8840:23:0:0:0:0:40
v0n2.nic.run. 156418 AAAA 2a01:8840:24:0:0:0:0:40
v0n3.nic.run. 156418 AAAA 2a01:8840:fa:0:0:0:0:40
v2n0.nic.run. 162015 AAAA 2a01:8840:25:0:0:0:0:40
v2n1.nic.run. 156418 AAAA 2a01:8840:fb:0:0:0:0:40
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0