[mikemaccana]

Follows Dean Little's review of the Time chapter: interest and funding now accrue by the Clock's timestamp rather than by elapsed slots. Price freshness stays in slots.

Merge after quicknode/solana-program-examples#151. This PR names last_accrual_timestamp, last_funding_timestamp and funding_rate_per_second, which that PR adds. The companion AI plugin's rule changes in quicknode/solana-finance-claude-plugin#66.

Why

A rate quoted per year or per hour only became a rate per slot through a guess at the slot length. The companion's lending default assumed 400 ms slots and charged twice the quoted APR once the network moved to 200 ms. A leader can move the timestamp by a second or two. At a 20% annual rate that is about a hundred-millionth of the debt, so the argument that seconds at the liquidation line are worth money does not hold for accrual.

Changes

• Time chapter. The accrual section now says interest and funding count seconds, and answers the leader-manipulation argument with numbers. The shorter-slot section now covers windows only, and a new War Story explains the SPL token-lending SLOTS_PER_YEAR constant, which truncated to 2 slots a second. The programs table and What You Learnt follow.
• Decision tree figure. The fourth question now asks whether it is a rate or a deadline quoted to somebody in human time.
• Halt section, corrected for Alpenglow. It said the first block after a restart carries a timestamp hours later, and that the vault's sixty-second window refuses the old price. Under Alpenglow the timestamp cannot jump: it trails real time and catches up. The section now says so, and lists the vault among the programs that check LastRestartSlot, as the companion's vault code already does.
• Other chapters. Lending, Perpetual Futures, Arithmetic of Money and Operating Financial Software follow the change, as do the glossary, the funding-index and rate-curve figures, and the Amazon description.

Checks

npm run lint, node scripts/check-figure-geometry.mjs and npm run build-pdf all pass on the branch after merging main.

🤖 Generated with Claude Code

https://claude.ai/code/session_01CXqcBq93zfcZ2F8jeoSaez

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