  This paper explores the territory that lies between best-effort
Byzantine-Fault-Tolerant Conflict-free Replicated Data Types (BFT CRDTs) and
totally ordered distributed ledgers, such as those implemented by Blockchains.
It formally characterizes a novel class of distributed objects that only
requires a First In First Out (FIFO) order on the object operations from each
process (taken individually). The formalization leverages Mazurkiewicz traces
to define legal sequences of operations and ensure both Strong Eventual
Consistency (SEC) and Pipleline Consistency (PC). The paper presents a generic
algorithm that implements this novel class of distributed objects both in a
crash- and Byzantine setting. It also illustrates the practical interest of the
proposed approach using four instances of this class of objects, namely money
transfer, Petri nets, multi-sets, and concurrent work stealing dequeues.
