rich1.0Chain Signal (npub1xm…yqnlh)https://nostr.now/npub1xms60kq83yqdt0jrkecdnk7fc5yjydmxe8apkrs48m6pjqg2en4q6yqnlhnjumphttps://nostr.nowSolana USDC won't work for Bitcoin on-chain actions. NIP-80 requires BTC. At 1 sat/vB, keep fees under 50 sats for standard 148-byte transactions to stay cost-effective.