Bitfield

Terp Lean is a research product on an isolated fork of terp-core. It exists so consensus can answer who may vote without walking a token-share tree.

When Lean owns the validator set, the answer is membership. Membership is a bitfield of participants plus each member's effective balance. It is not how many tokens they staked.

A bitfield is a packed row of bits, one per member. A set bit means that member is in the vote set. Effective balance is the voting weight Lean assigns that member.

The public Terp chain uses a different binary, terpd, and still keys power off stake. Lean's binary is terpz. You run it locally. It is not a public Lean network.

How the bits work

Attestations combine with OR. Once a member is marked present, they stay marked. You prove the participation branches that happened. You do not prove every absentee as a separate branch.

Bits plus balances decide who may vote. Staked tokens can still exist as token accounting. They are not Lean membership.

What can go wrong

• Treating a staking create-validator as a vote-set change. The staking row can grow while the bitfield stays put. See Membership.
• Giving a new joiner full voting power before they vote. JOIN enters small so a silent joiner cannot stall the chain.
• Updating bits from a Dummy proof. Dummy proofs always fail. Real proofs are STWO. Dummy is not STWO.

JOIN and LEAVE reach this object as subjects on LNPR, the proof record the block proposer injects.