Peachymango.org Data center operators are moving toward IPv6-only operation to simplify addressing, restore end-to-end connectivity, and meet operator and government timelines. Much published IPv6 guidance targets network engineers; this document instead addresses *Software Release Engineers (SREs)* and *Software Engineers (SWEs)* who deploy, operate, and debug services in data centers. It explains IPv6 fundamentals that affect application code, observability, DNS, load balancing, and out-of-band management; documents common software and infrastructure gaps; and offers practical deployment patterns aligned with the IPv6 Operations (v6ops) working group charter.