- Peter Todd has become the lead maintainer of Slipstream, a MARA-backed private transaction relay service.
- Slipstream was used to help move more than 9000 BTC from Coldcard-affected multisignature wallets while keeping recovery transactions out of the public mempool.
- The service has also supported experimental Bitcoin transactions, including StarkWare’s first quantum-safe transaction to reach mainnet.
Peter Todd Takes Lead Role at MARA’s Slipstream
Peter Todd has independently announced that he is now the lead maintainer of Slipstream, linking the role to the broader debate over private mempools and alternative Bitcoin transaction-routing channels.
“Announcement: I’m now the lead maintainer of Slipstream @MARAFoundation_I’ll actually be giving a short talk on private mempools at the upcoming TABConf – it’s really interesting how Slipstream was useful during the coldcard hack.”
— Peter Todd, in a post on X
Todd’s reference to the Coldcard incident highlights how private transaction routing has implications beyond a technical discussion about Bitcoin infrastructure. In some circumstances, keeping a transaction out of public view can affect whether an attacker has an opportunity to interfere with the transaction before it is confirmed.
How Bitcoin Relay Policy Differs From Consensus
Bitcoin’s relay policy is separate from the network’s consensus rules. Bitcoin Core documentation describes relay policy as a collection of additional, locally configurable rules that nodes apply to unconfirmed transactions before accepting them into their mempools. Those rules no longer apply once a transaction has been included in a block.
Slipstream enables users to bypass the normal public relay path. MARA introduced the service in February 2024 to process large or non-standard transactions. Through MARA Pool, users can submit transactions directly to the Pool instead of relying on a public relay method, while transactions remain subject to Bitcoin’s principles and applicable fee requirements.
Coldcard Recovery Transactions and Private Mempools
In a July 2026 advisory, Coldcard warned that firmware released from 2021 through July 2026 could be vulnerable to poor entropy generation. Users affected by the flaw were advised to regenerate their secrets and take the necessary steps to move their funds on-chain immediately.
A complication involved recovery transactions that exposed a multisignature script. If such a transaction remained unconfirmed for too long, an attacker could potentially observe it and attempt to create a competing transaction with a higher fee. Todd identified Slipstream as a way to reduce that exposure by keeping the transaction out of the public mempool until it was mined.
“because they promise to keep your transaction – and thus pubkeys – secret until they’re already in a block. Dramatically reducing the ability of the attacker to steal the funds.”
— Peter Todd, quoted by Bitcoin Magazine
Todd said the protection was most relevant when affected addresses had not previously been reused:
“If you’ve already reused addresses, this isn’t relevant, and you should just try to move your funds ASAP. But if you haven’t, MARA may be able to help.”
— Peter Todd, quoted by Bitcoin Magazine
MARA Foundation later said that Slipstream facilitated the transfer of over 9000 BTC from susceptible multisignature wallets.
Slipstream’s Role in Bitcoin Experiments
Slipstream has also been used for experimental Bitcoin transactions. Cryptopolitan previously reported that StarkWare’s first quantum-safe Bitcoin transaction reached mainnet through Slipstream after failing to pass through the standard mempool route.
Private channels such as Slipstream give miners an alternative way to process transactions that may be blocked by public relay policies. The approach can be used during a security incident, such as the Coldcard recovery effort, or for technical experiments such as StarkWare’s quantum-safe transaction.
Why This Matters
Private transaction channels change how Bitcoin users can interact with miners before a transaction enters a block. They may provide an important route for transactions that need protection from public observation or that do not fit standard relay policies. However, this processing takes place outside the public mempool, raising broader questions about transparency, transaction routing, and the growing role of miner-operated channels in Bitcoin infrastructure.
Peter Todd’s involvement places additional attention on Slipstream as the debate over private mempools develops. His planned talk at TABConf is expected to address the subject, while Slipstream’s use in Coldcard recovery and quantum-safe transaction experiments illustrates the different situations in which direct miner submission can be used.
Frequently Asked Questions
What is Slipstream?
Slipstream is a MARA-backed private transaction relay service that allows users to submit Bitcoin transactions directly through MARA Pool rather than relying on the standard public relay path.
Why was Slipstream used in the Coldcard recovery effort?
Slipstream was used to help keep recovery transactions and the associated public keys out of the public mempool until the transactions were mined. MARA Foundation said the service facilitated the transfer of over 9000 BTC from susceptible multisignature wallets.
What other Bitcoin transactions has Slipstream supported?
Slipstream has also supported experimental transactions, including StarkWare’s first quantum-safe Bitcoin transaction to reach mainnet after it failed to pass through the standard mempool route.