OSS Projects
Building a distributed system means building node discovery, liveness detection, messaging, and agreement before getting to the actual work. Alopex Chirps takes on exactly those four. This covers what it handles and what it does not, why QUIC was chosen, and how openraft came to be the consensus layer.
In a network where neither the identity nor the number of participants is known, one node one vote does not hold. Probabilistic finality in PoW, the structure by which PoS relies on economic penalties rather than impossibility, Solana and Avalanche, and the option of avoiding agreement — with the criteria for choosing among them. Part 4 of a 4-part series.
The world in which nodes send signed, contradictory information. The meaning of the constant n=3f+1, PBFT's three-phase voting, Tendermint's locking rules, HotStuff's quorum certificates, and what the DAG-BFT designs since Narwhal separated and what they removed. Part 3 of a 4-part series.
The family of algorithms for the crash failure model, where nodes stop but do not lie. From the single tool Paxos relies on — quorum intersection — through Raft's decomposition, EPaxos, Multi-Raft, and the parts outside the papers: persistence ordering and linearizable reads, with minimal code. Part 2 of a 4-part series.
A node that stops responding may have crashed, or it may merely be slow; the two cannot be told apart. This part separates leader election, ordering, and commitment into three distinct problems, and covers the practical meaning of FLP impossibility, split brain and fencing tokens, and the boundary between the replicated log and the applied state. Part 1 of a 4-part series.
Building a distributed system means building node discovery, liveness detection, messaging, and agreement before getting to the actual work. Alopex Chirps takes on exactly those four. This covers what it handles and what it does not, why QUIC was chosen, and how openraft came to be the consensus layer.
In a network where neither the identity nor the number of participants is known, one node one vote does not hold. Probabilistic finality in PoW, the structure by which PoS relies on economic penalties rather than impossibility, Solana and Avalanche, and the option of avoiding agreement — with the criteria for choosing among them. Part 4 of a 4-part series.
The world in which nodes send signed, contradictory information. The meaning of the constant n=3f+1, PBFT's three-phase voting, Tendermint's locking rules, HotStuff's quorum certificates, and what the DAG-BFT designs since Narwhal separated and what they removed. Part 3 of a 4-part series.
The family of algorithms for the crash failure model, where nodes stop but do not lie. From the single tool Paxos relies on — quorum intersection — through Raft's decomposition, EPaxos, Multi-Raft, and the parts outside the papers: persistence ordering and linearizable reads, with minimal code. Part 2 of a 4-part series.
A node that stops responding may have crashed, or it may merely be slow; the two cannot be told apart. This part separates leader election, ordering, and commitment into three distinct problems, and covers the practical meaning of FLP impossibility, split brain and fencing tokens, and the boundary between the replicated log and the applied state. Part 1 of a 4-part series.
