Nullifier Queue
ZK Compression · Bottom
A FIFO queue in Light Protocol holding hashes of spent compressed accounts. When a compressed account is transferred or burned, its nullifier is added to prevent double-spending. The Forester service asynchronously drains the queue, zeroing old Merkle tree leaves. If the queue fills before processing, a temporary liveness issue occurs — spend transactions fail until space is freed. This is a protocol-level, not application-level concern.