com_r35157_nenjim-hubd-impl_ref/openspec/changes/archive/2026-09-04-84-validate-jup-signer-on-wallet-construction/proposal.md

Why

Nenjim currently constructs Solana wallet components without proving that their external jup signer configuration is usable. A missing production signer was therefore discovered only during transaction signing, after the operation could already have an uncertain outcome.

What Changes

• Make SolanaWalletImpl validate its required constructor inputs before use.
• Run jup --version during construction and require the explicitly supported version 0.10.1.
• Load the jup key catalogue during construction, require the configured signer name to exist, and require its public address to match the wallet address.
• Fail construction with actionable diagnostics when the executable, version, key catalogue, signer, or address is invalid, without exposing private key material.
• Retain signer-address verification after each actual signing operation as defence in depth.

Capabilities

New Capabilities

• solana-wallet-signing: Defines fail-fast construction and external signer validation for the reference Solana wallet implementation.

Modified Capabilities

None.

Impact

The reference implementation at com.r35157.cryptowallet.solana.impl.ref.SolanaWalletImpl gains a startup dependency on executable jup version 0.10.1 and a matching configured signer. Nenjim Hub initialization will now fail before registering the complete passive graph when a configured wallet cannot later sign transactions. No public API signatures, Detag configuration, generated sources, tests, or unrelated services change.