Vol. 1 · 7 Jun 2026
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The protocol

Validators & the permissioned set

Tempo launched with a permissioned validator set — approved operators including Stripe, Visa, Zodia Custody, and MoneyGram — with a stated roadmap toward permissionless validation.

4 min read · Updated 2026-06-08

Permissioned at launch

Tempo launched with a permissioned validator set: operators are approved rather than open to anyone. The project has stated a roadmap toward permissionless validation, but at launch the set is curated.

This is a common pattern for payment networks that need known, accountable operators from day one. It trades some openness for operational reliability and clear lines of responsibility.

Who validates

Announced corporate validators include Stripe, Visa, Zodia Custody, and MoneyGram — a mix of payment networks, custodians, and money-transfer firms. Having established financial institutions run the set is part of how Tempo positions itself as a payments rail rather than a speculative chain.

Because consensus is Simplex BFT, the set's behaviour is governed by the 2f+1 quorum rule: the chain progresses only with a supermajority, and halts rather than finalising conflicting blocks if more than one-third are unavailable.

Why this matters for users

A permissioned set means the liveness and safety of the chain depend on a known group of operators. The upside is accountability and predictable operation; the trade-off, relative to a fully permissionless chain, is that participation in block production is gated.

For a neutral reading, treat decentralization as a dimension to watch over time as Tempo executes its stated path toward permissionless validation, rather than a settled property today.


Keep reading

Related


Citations

Sources

  1. [1]Tempo blog — Stripe, Visa, and Zodia Custody join as validators
  2. [2]Tempo blog — MoneyGram joins as first remittance validator
  3. [3]Tempo blog — Introducing Tempo (roadmap to permissionless)

tempowiki is a neutral, sourced reference. Every claim above is drawn from the cited sources; where a detail is uncertain it is omitted rather than guessed.


Answer-first

Frequently asked

Is Tempo permissionless?
Not at launch. Tempo launched with a permissioned validator set — operators are approved rather than open to anyone — with a stated roadmap toward permissionless validation.
Who are Tempo's validators?
Announced corporate validators include Stripe, Visa, Zodia Custody, and MoneyGram.
What stops validators from finalising bad blocks?
Simplex BFT requires a 2f+1 quorum and halts rather than finalising conflicting blocks if more than one-third of validators are unavailable, prioritising safety over liveness.