Sprey Processing verification — 2026-09-12

This checkpoint records behavior directly verified on 2026-09-12.

WDK wallet

The existing WDK wallet sprey-processing was confirmed to derive public destinations for TRON, EVM, Spark, and Bitcoin. The wallet recovery material remains outside BTCPay Server.

Spark

Spark address derivation succeeded for account indices 0 and 1 through the WDK CLI. Both returned valid spark1... addresses.

No end-to-end Lightning payment is claimed here. Flint remains the currently configured BTCPay Lightning backend while the long-term WDK Spark integration model is still under evaluation.

Bitcoin

After upgrading the WDK CLI from beta.3 to beta.4, Bitcoin derivation initially failed because of an @noble/hashes/hmac package-export dependency conflict. Updating the WDK and BTC module dependencies inside the local CLI installation resolved the error.

The standard WDK command then derived Bitcoin index 0 successfully.

Verified Bitcoin first receive address:

bc1qjthy0ur438kdyzunyy2u00ftaswvqg2j7gu4v5

The Bitcoin account uses Native SegWit BIP84 with account path:

m/84'/0'/0'

Sparrow

A Sparrow wallet named Sprey Processing WDK BTC was created from the same sprey-processing wallet recovery material using Native SegWit/BIP84.

Its first receive address matched the WDK Bitcoin index-0 address exactly.

BTCPay watch-only replacement

The Sprey Processing Store Bitcoin wallet was replaced with the account xpub from Sprey Processing WDK BTC.

Before confirmation, BTCPay displayed address 0/0 as the same verified address shown by WDK and Sparrow.

Configured BTCPay metadata:

Label:              Sprey Processing WDK BTC
Master fingerprint: ad7e60ab
Account key path:   m/84'/0'/0'

The resulting ownership boundary is:

sprey-processing
├── WDK BTC account
├── Sparrow spending wallet
└── BTCPay account xpub only (watch-only)

BTCPay does not receive Bitcoin signing authority.

End-of-day status

Verified:

• WDK Spark derivation at indices 0 and 1;
• WDK Bitcoin Native SegWit derivation;
• BIP84 account path m/84'/0'/0';
• identical Bitcoin first receive address in WDK, Sparrow, and BTCPay;
• replacement of the BTCPay Bitcoin wallet with the WDK-derived watch-only account;
• Sparrow retains merchant-side Bitcoin spending authority.

Pending:

• small real BTC invoice/payment verification using the new watch-only account;
• end-to-end Lightning payment verification;
• final long-term Flint versus direct WDK Spark integration decision;
• real USDt settlement tests;
• hosted subscription paid-flow verification.