Choose the right protocol
Compare message meaning, session recovery, transport, and encoding before interpreting latency benchmarks.
CONNECTIVITY / INTERFACE DESIGN
PROTOCOLS.
NOT SLOGANS.
Choose an interface for the workflow it can support. Start with semantics and recovery, then test equivalent work under equivalent conditions.
Message meaning
Describe the actual business operations before selecting a library. Orders, cancellations, executions, account queries, and market observations need distinct result types. The FIX reference in the full guide provides a standards-based starting point for separating message meaning from its representation.
Session and transport
A connection has startup, steady-state, interruption, and recovery behavior. Ask how a provider establishes a consistent view, identifies messages where applicable, and resolves missed information. A persistent stream removes neither application backlogs nor the need to rebuild state after interruption.
Encoding and performance
Readable formats and binary formats make different representation choices. Compare them on the same event set, with the same correctness and validation requirements. A faster parser is meaningful only in the context of the full path being measured. Do not assume a universal ranking from an encoding label.
A requirements-first evaluation
For each candidate interface, record needed data coverage, order operations, identifiers, permissions, current limits, and recovery evidence. Mark unsupported features and unanswered questions explicitly. Evaluate certification and operational ownership alongside implementation effort. Keep research access distinct from approval for live use.
Use the layers together
A mixed architecture can assign different interfaces to reference data, streaming observations, and private execution events. Preserve identity and uncertainty across those boundaries. The full protocol comparison below develops this approach without inventing latency figures or describing every technology as an equivalent product.
THE FIELD NOTES
GO DEEPER.
The HFT API blueprint
Design the complete signal-to-order path with explicit state, data freshness, risk checks, and recovery.
Bitcoin order flow
Build a reliable exchange-based bitcoin research workflow with correct book updates and recoverable order identities.