  Trustless systems, such as those blockchain enpowered, provide trust in the
system regardless of the trust of its participants, who may be honest or
malicious. Proof-of-stake (PoS) protocols and DAG-based approaches have emerged
as a better alternative than the proof of work (PoW) for consensus. This paper
introduces a new model, so-called \emph{\stakedag}, which aims for PoS
consensus in a DAG-based trustless system. We address a general model of
trustless system in which participants are distinguished by their stake or
trust: users and validators. Users are normal participants with a no assumed
trust and validators are high profile participants with an established trust.
We then propose a new family of stake-based consensus protocols $\mathfrak{S}$,
operating on the DAG as in the Lachesis protocol~\cite{lachesis01}.
Specifically, we propose a stake-based protocol $S_\phi$ that leverages
participants' stake as validating weights to achieve more secure distributed
systems with practical Byzantine fault tolerance (pBFT) in leaderless
asynchronous Directed Acyclic Graph (DAG). We then present a general model of
staking for asynchronous DAG-based distributed systems.
