EVM Canon Base – FIFO Cost-Basis Lot Matching

Choose this endpoint when you need strict FIFO (first-in, first-out) cost-basis matching with exact decimal arithmetic — the standard method required by many tax jurisdictions for cryptocurrency. Prefer this over HIFO (which minimizes gains by consuming highest-cost lots first) or average-cost basis when the user specifically needs FIFO compliance or when the tax authority mandates it. Use instead of the net-position endpoint when realized gain per disposal is needed, not just net balance.

• Insufficient lot quantity — disposals exceed total acquisition quantities, returning an error or partial match
• Malformed decimal precision — mismatched decimal places between lots causing computation errors
• Missing required fields — acquisition or disposal records lacking timestamps or quantities
• Out-of-order timestamps — lots or disposals with ambiguous or identical timestamps producing non-deterministic FIFO ordering
• Empty lot list — no acquisition records provided, returning zero matches