aura

aura is a "game engine for traders." It is a Rust framework — and a playground — for authoring trading strategies as composable dataflow nodes, backtesting them deterministically and massively in parallel, validating them (sweep / Monte-Carlo / walk-forward), and freezing a validated strategy into a standalone bot with a broker connection. Its differentiator is the World: a program that constructs and orchestrates whole families of backtests, not the single run.

This README is a discoverability map of the shipped aura CLI — what commands exist and what they do. It deliberately keeps per-flag detail light; the two authoritative sources for exact syntax are always:

• aura <command> --help — the exhaustive flag grammar.
• The design ledger (docs/design/INDEX.md) and glossary (docs/glossary.md) — the concepts and invariants behind the surface.

Build & run

aura is a Cargo workspace. Build everything and you get one binary named aura:

cargo build --workspace          # binary at target/debug/aura
cargo build --workspace --release  # optimized, at target/release/aura

Invoke it as aura <command> … (examples below use the plain name).

Concepts in one breath

• Blueprint — a serialized signal graph as data: a param-generic price → bias node graph. A blueprint file (blueprint.json) is the unit a downstream consumer loads and executes or varies.
• Open vs. closed — a blueprint with unbound (free) numeric knobs is open; one with every knob bound is closed. A plain exec wants closed; naming a knob as a campaign axis (or an exec --override) is what reopens it.
• Family — the set of runs a campaign document's process pipeline produces over a blueprint (a sweep grid, a Monte-Carlo seed set, a walk-forward window sequence). Families are persisted in a content-addressed store and can be listed, ranked, and reproduced.
• Axis — one named, sweepable knob of a blueprint (e.g. fast.length), bound with a comma-separated value list. A gang fuses several sibling knobs into one axis (one value drives all members).

Executing a document

aura exec <target> (#319) is the one executor verb: <target> is either a loaded blueprint file (a single synthetic run) or a campaign document (a .json file or its registered 64-hex content id — instruments × windows × strategy × param axes × process, see docs/authoring-guide.md §3). graph renders a blueprint's structure so a mis-wire is visible before a run.

Command	Purpose
aura exec <bp.json>	Run one backtest of a closed blueprint and print its report. An open (free-knob) blueprint is refused with a clean error — bind it, or vary it as a campaign axis.
aura exec <bp.json> --override <node.param>=<value>	Reopen one bound param for this single execution only (the value is recorded raw in the manifest); repeatable.
aura exec <bp.json> --tap <name>=<fold>	Subscribe a declared tap to a fold (record/count/sum/mean/min/max/first/last) for this run; repeatable.
aura graph <bp.json>	Render the blueprint's structure as an interactive HTML DAG so a mis-wire is visible before a run. Omit the file to render the built-in sample; a named-but-unreadable file is a usage error.
aura graph introspect --params <bp.json|id>	Discover a blueprint's open, sweepable knobs. Prints each as <name>:<kind>, bound params trailing default=<value>. Run this first to learn the axis names for a campaign document.
aura exec <campaign.json|id> [--parallel-instruments <n>]	Execute a campaign document — a grid family, gates, walk-forward, Monte-Carlo, and cross-instrument generalization per its process document, one cell per (strategy, instrument, window).
aura runs families	List every persisted family (id, kind, member count).
aura runs family <id> [rank <metric>]	List one family's members, optionally ranked best-first by an R metric (e.g. sqn_normalized, expectancy_r).
aura reproduce <family-id>	Re-derive every member of a persisted family from the content-addressed store and check it is bit-identical (the C18/C1 determinism guarantee).

Important contract — every open knob is mandatory on a campaign axis. A campaign document's strategies[].axes must name every open knob graph introspect --params lists: there is no default value — pin a knob you don't want to vary with a single-value axis ({"kind":"I64","values":[4]}). Omitting one is a clean error naming the missing knob, not a silent default.

Use aura exec --help for the exact flag grammar, docs/authoring-guide.md for the campaign document shape (data window, naming, presentation/emit).

Authoring & introspecting topology

A blueprint is authored declaratively from a JSON op-list: an ordered list of by-identifier construction ops replayed against the standard node vocabulary. Adding a new node type to that vocabulary is Rust, not JSON — see docs/authoring-guide.md, §0, "Authoring a new node in Rust".

Command	Purpose
aura graph build	Read an op-list document on stdin, build the blueprint, and print its canonical JSON to stdout (no trailing newline — it is the content-addressed artifact).
aura graph introspect --vocabulary	List every node type available to op-lists.
aura graph introspect --node <T>	Show one type's input ports, output fields, and param paths (with the bind-value form).
aura graph introspect --unwired	Read a partial op-list on stdin and list its still-open interior slots.
aura graph introspect --content-id	Read an op-list on stdin and print the SHA-256 content id of the blueprint it would build.
aura graph introspect --identity-id	Read an op-list on stdin and print the SHA-256 identity id — the topology's debug-name-blind id, so two documents (or an op-script and a Rust-built blueprint) expressing the same topology print the same id. Combinable with --content-id (both ids, one per line, content id first).

Op-list shape

Each element is one op, tagged by "op". Node params are bound with the typed Scalar form — a tagged, capitalized-kind object: {"I64": 5}, {"F64": 1.5}, {"Bool": true}. A worked example (an SMA-crossover → bias signal):

[
  {"op":"source","role":"price","kind":"F64"},
  {"op":"add","type":"SMA","name":"fast","bind":{"length":{"I64":2}}},
  {"op":"add","type":"SMA","name":"slow","bind":{"length":{"I64":4}}},
  {"op":"add","type":"Sub"},
  {"op":"add","type":"Bias"},
  {"op":"feed","role":"price","into":["fast.series","slow.series"]},
  {"op":"connect","from":"fast.value","to":"sub.lhs"},
  {"op":"connect","from":"slow.value","to":"sub.rhs"},
  {"op":"connect","from":"sub.value","to":"bias.signal"},
  {"op":"expose","from":"bias.bias","as":"bias"}
]

Piping this document into aura graph build emits a blueprint.json you can then feed to exec above:

aura graph build < crossover.ops.json > crossover.bp.json
aura graph introspect --params crossover.bp.json

The op kinds are source, input, add, feed, connect, expose, tap, gang, doc, and use (tap declares a recorded measurement point on an interior wire; doc declares the composite's one-line meaning, required at register — C29; use splices a registered blueprint in as a nested composite, by content id or label; add additionally takes an args object for arg-bearing types (Session, LinComb, CostSum) — structural, non-scalar construction consumed before bind; see the authoring guide). See aura graph introspect --node <T> for a type's exact ports and the op-script grammar in the design ledger for the full semantics.

Where to go deeper

• aura <command> --help — exhaustive, always-current flag grammar.
• docs/design/INDEX.md — the design ledger: architecture, invariants, the World.
• docs/glossary.md — canonical terminology (blueprint, family, axis, sweep / Monte-Carlo / walk-forward, R, content-id, …).