ENSIP-9 primary sources — 2026-05-13

What I reviewed

• ENS documentation:
  • https://docs.ens.domains/ensip/9
  • https://docs.ens.domains/ensip/
  • https://docs.ens.domains/ensip/11
  • https://docs.ens.domains/ensip/19
• ENS implementation surfaces:
  • https://github.com/ensdomains/ensips
  • https://github.com/ensdomains/resolvers
  • https://github.com/ensdomains/address-encoder
  • https://raw.githubusercontent.com/ensdomains/resolvers/master/README.md
  • https://raw.githubusercontent.com/ensdomains/address-encoder/master/README.md

Key takeaways from primary sources

• ENSIP-9 is the real lower-layer pivot that makes ENS multichain at the resolver level. It standardizes addr(node, coinType) rather than proliferating chain-specific ad hoc fields.
• The most important mechanism choice is storage as native binary data, not user-facing text. That keeps the onchain interface consistent while pushing human-readable formatting and checksum presentation to client/tooling layers.
• The address-encoding section shows ENSIP-9 is really a codec-normalization standard as much as a resolver API standard. Bitcoin-like scriptPubKeys, SegWit witness programs, EVM hashes, Ripple variants, CashAddr, and Bech32-style addresses all get mapped into one interface.
• Backwards compatibility with ENSIP-1 is a core part of the design. Ethereum addr(node) is preserved as the coinType-60 special case of the broader multichain interface rather than being replaced.
• ENSIP-11 and ENSIP-19 make ENSIP-9’s long-term importance clearer: ENSIP-11 fixes scaling problems around EVM coin-type assignment, and ENSIP-19 builds verified multichain primary-name logic on top of ENSIP-9’s address layer.
• The @ensdomains/address-encoder library is the most concrete proof that ENSIP-9 is practical ecosystem plumbing rather than just a specification page. Shared codec libraries turn the standard into implementation default behavior.

Specific source signals worth retaining

• ENSIP-9 is the best direct source for the resolver interface, event shape, encoding rules, and backwards-compatibility requirements.
• The ENSIP index page is the best compact source for status and for seeing ENSIP-9 in the larger ENS standards family.
• ENSIP-11 is the best source for the later pressure point ENSIP-9 creates around EVM chain growth and SLIP-44 dependence.
• ENSIP-19 is the best source for the downstream consequence: once addresses are keyed by coin type, reverse and primary-name logic can also become coin-type aware.
• The address-encoder README is the best implementation-facing signal that ENS address codecs became shared tooling, not merely prose in the standard.

Why this entry belongs in the corpus

• It isolates the shared address-representation layer beneath ENS multichain naming and wallet identity UX.
• It helps separate chain/account codec policy from higher-layer reverse naming, primary-name, and auth/session standards.
• The durable insight is that multichain naming systems quietly depend on address-codec governance and coin-type registries long before users ever see a name in a wallet.