manyfold 0.1.39

PyO3-backed Manyfold RFC scaffolding and in-memory runtime.

manyfold

Manyfold is a component library for execution graphs.

It helps make graph-shaped programs easier to build, inspect, and explain. Routes, schemas, buffers, demand, time, payload access, writes, taints, and lineage are modeled as graph concerns instead of being hidden in callback code or queue configuration.

Think of it as a logical board: routes are traces, ports are pads, components shape execution, and overlapping regions show where ownership, policy, and data flow meet.

This repository is an RFC-stage Python package with a PyO3/Rust extension. It is not a production runtime yet, but the package is runnable and the examples exercise the supported surface.

Start Fast

uv sync
uv run python examples/simple_latest.py
uv run python -m unittest tests.test_examples

A Small Graph in Motion

Publish Values

from dataclasses import dataclass

from manyfold.architecture import PubSub


@dataclass(frozen=True)
class Temperature:
    degrees: float
    unit: str


temperature = PubSub()

temperature.publish(Temperature(degrees=72.4, unit="F"))
temperature.publish(Temperature(degrees=72.9, unit="F"))
latest = temperature.latest()
latest_row = temperature.query_one(
    """
    SELECT pad_name, offset + 1 AS seq_source, degrees, unit
    FROM stream
    ORDER BY event_time DESC, process_sequence DESC
    LIMIT 1
    """
)
if latest is not None and latest_row is not None:
    print(f"latest #{latest_row['seq_source']}: {latest.degrees}{latest.unit}")

Output:

latest #2: 72.9F

When a topic matters, pass it explicitly. Dotted topics keep the same ownership shape as a route name:

• owner is the component or subsystem responsible for the signal.
• family groups related streams.
• stream names this specific signal.

PubSub is a stream backed by PubSub delivery and a Rust SQL stream processor, so latest() is an ordinary ordered query_one(...) under the hood. If no topic is provided, the stream gets an ephemeral UUID5 topic. latest() returns a row object, so SQL-backed fields can be read as latest.degrees or latest["degrees"]. The SQL table exposes pad_name for filtering and joins. If no schema is provided, the first structured model publish fixes the stream schema lazily. Pydantic models work through their model_fields and model_dump() surface; dataclasses work through type annotations. The current runtime encodes those values as FlatBuffer bytes in payload and materializes the logical fields as typed SQL columns during Rust ingestion. Callers may still pass generated FlatBuffer bytes, builder Output(), or table objects. The queue assigns a default event_time when callers do not provide one, and key defaults to None; distributed queue implementations own their ordering contract.

Manyfold-native architecture elements remain available from manyfold.architecture.native for lower-level topology descriptions, but PubSub is the primary application stream surface. Behavior-heavy substrates stay backed by the runtime implementation.

Stats: Compute Values

temperature = route(
    owner="sensor",
    family="environment",
    stream="temperature",
    schema=Schema.float(name="Temperature"),
)
average_temperature = temperature.derivative_route(
    stream="average_temperature",
    schema=Schema.float(name="AverageTemperature"),
)

subscription = graph.observe(temperature, replay_latest=False).moving_average(
    window_size=3
).connect(average_temperature)
for reading in (72.4, 72.9, 73.7):
    graph.publish(temperature, reading)
subscription.dispose()

latest_average = graph.latest(average_temperature)
assert latest_average is not None
print(f"average: {latest_average.value:.1f}F")

node = next(
    node
    for node in graph.diagram_nodes()
    if dict(node.metadata).get("statistic") == "moving_average"
)
print(dict(node.metadata))

Output:

average: 73.0F
{'statistic': 'moving_average', 'storage': 'sliding_capacitor', 'window_size': '3'}

The shape is the same: computed values are just values published to another typed route. The moving average also renders as a graph-visible node backed by a sliding capacitor, so derived state and operational inspection stay in the same vocabulary.

Model Consensus

from manyfold import Consensus

consensus = Consensus.install(graph, nodes=("node-a", "node-b"))
consensus.tick(1)
consensus.tick(2)
consensus.propose(1, "set mode=auto")
consensus.propose(2, "set temp=21")

print(consensus.latest_leader())
print(consensus.latest_log())

Output:

('node-a', 3, True)
((1, 'set mode=auto'), (2, 'set temp=21'))

The consensus component uses Raft-shaped leader election and replicated-log concepts from Diego Ongaro and John Ousterhout's “In Search of an Understandable Consensus Algorithm” (USENIX ATC 2014).

Read Next

• Onboarding: repo setup, first commands, and where to look first.
• Using Manyfold: routes, graphs, observation, flow components, and examples.
• Performance: how to represent performance concerns as graph concerns.
• Distributed systems catalog: higher-level component ideas.
• v1.0.0 Vision: a far-off but reachable target for distributed graph computing and primitive building.
• Wiregraph RFC: the larger design target.

What It Models

• Typed routes for logical signals.
• Replayable latest-value reads and Rx-style observation.
• Graph-visible node thread placement for main, background, pooled, or isolated execution.
• Graph-visible capacitors, resistors, watchdogs, mailboxes, windows, and joins.
• Explicit demand, retention, lazy payload access, and write-shadow state.
• Lineage, taints, route audit snapshots, and topology queries.
• Local file-backed stores and a small consensus component scaffold.

The public Python surface is intentionally narrow at the top level. Advanced helpers live under manyfold.graph, and the examples are the best way to see which parts are supported today.

Examples

The examples/ directory is organized as a short path through the mental model. Start with a route, derive values, add explicit demand, then move into joins, watermarks, planning, consensus, and taint-aware runtime behavior. The supported examples are validated by the regular unittest run so they do not drift away from the API.

Start here: publish changing state and read the latest value

• examples/simple_latest.py: Smallest changing-signal publish/read-back example.

Layer computation: publish derived values

• examples/average_temperature.py: Compute and publish a rolling average from temperature samples.

Control the flow: make downstream demand visible

• examples/rate_matched_sensor.py: A one-slot capacitor coalesces bursty reads behind explicit demand.

Fuse streams: coordinate independent sensors

• examples/imu_fusion_join.py: Capacitors stage accelerometer and gyro streams before an event-time join.

Reason in time: release data by watermark progress

• examples/rolling_window_aggregate.py: A capacitor discharges samples behind explicit event-time watermarks.

Scale the graph: plan repartition work explicitly

• examples/cross_partition_join.py: A repartition join with skew metrics and planner output.

Capstone: wire a Raft-shaped consensus component

• examples/raft_demo.py: The Consensus component wires Raft election defaults from graph primitives.

Audit the hard parts: mark nondeterminism on purpose

• examples/ephemeral_entropy_stream.py: Per-request entropy derivation that taints determinism explicitly.

More involved operator, query, transport, mesh, and security coverage stays in tests/test_graph_reactive.py, with archived exploratory scripts kept under examples/archived/. The example manifest, README featured-example list, and RFC reference suite all derive from the shared example catalog, so supported versus archived status lives in one place.

Verify

Use uv run for Python commands.

cargo test
uv run ruff check
uv run python -m unittest discover -s tests -p 'test_*.py'
uv run python -m manyfold.rfc_checklist_gen --check
uv run manyfold-example-catalog --check
uv run python -m examples.catalog --check-readme

Repo Map

• python/manyfold/: Python wrapper API.
• src/: Rust in-memory runtime and PyO3 extension.
• examples/: runnable examples covered by tests.
• tests/: unittest suite.
• docs/: onboarding, usage, performance notes, release notes, and RFC docs.