Tracing a failed swap across three programs
A reader arrived with a transaction that showed success in their wallet history but failed to deliver the expected token. During intake they shared the signature and noted they had already checked the fee payer balance.
In the workshop we opened Solscan and Solana FM side by side, comparing how each displayed inner instructions. The failure sat inside instruction four — a slippage check on a routing program — not in the outer transfer the reader had focused on.
We spent twenty minutes mapping account keys to the glossary entries for associated token accounts and program-derived addresses. The reader left with a handwritten flow diagram and later emailed that they applied the same method to two subsequent swaps without assistance.
They noted the session did not cover how to prevent slippage failures in future trades, which was outside the reading-library remit we agreed to at booking.