The canvas placed nodes with dagre, which orders nodes but knows nothing
about ports: an edge leaves a particular handle and lands on a particular
one, so two producers feeding a consumer in the other order crossed just
before they landed however well the nodes were arranged. The graph was not
a multigraph either, so two messages between one pair of nodes collapsed
into one before crossings were counted, and the endpoint labels were laid
out as 220-wide cards with every handle stacked on a single pixel.
ELK's layered algorithm replaces it. Every declared port is handed to it as
a fixed point on the node's rim, at the fraction `portFraction` puts the
handle at — which the node components now render from the same function —
so what the crossing count is minimised over is what ends up on the screen.
Measured on this installation's flows, with the labels included: `home`
goes from 51 crossings to 6 across and 70 to 29 down, `demo_training` 27 to
5 and 59 to 32, and every graph is the same size or smaller.
The engine answers asynchronously and is a chunk of its own, so positions
became state: the canvas draws nothing until the first layout lands, and an
edit keeps the arrangement it had rather than flashing through the corner.
The entry chunk is untouched and the flow route's own chunk came down 167
to 121 kB, since dagre used to be in it.
Two things the crossings made worse come with it. A hovered edge resolves
to full strength so one line can be followed through a busy rank, and a
feedback edge — one whose target the layout put behind its source — swings
out into a lane beside the graph instead of being drawn through everything
between its ends, which is what "House history" was reported for.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U6vyQvfX249hsv9YPmsYYg
A flow's inputs are the messages it takes from outside — a dashboard control,
a run, the API — and its outputs are what a batch run reports. Both existed in
the document and in the engine, and neither had any UI: the values looked
hard-coded on the canvas and the Run button always used the declared defaults.
The canvas now draws each as a labelled endpoint, the way it already draws a
dashboard tile or another flow, skipping an input something else already
accounts for. The flow panel edits them — mode, name, type, starting value,
and for a live flow the value it currently holds with a way to put a new one
in. Pressing Run on a batch flow asks for its parameters first.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NUb8YpL2s3gmN9WTACTt4q
The canvas lays itself out: a layered graph, left to right on a desktop and
top to bottom on a phone, with room reserved for the value each edge carries.
Nodes cannot be dragged and `NodeDef.position` is gone from the document —
a graph nobody can arrange is one worth keeping small, which is what keeps
flows atomic. Endpoints join the same layout, so their lanes and the
localStorage that remembered where they were dragged go too.
Mobile, per the new Responsive section of DESIGN-GUIDELINES.md: the dock caps
its width and wraps instead of running off the screen, the dashboard stacks
into one column rather than shrinking a wall panel to a fifth of its size, and
Home stops widening its grid track past the viewport. A Playwright project at
a phone's width fails the build when a screen no longer fits.
Along the way: publish is the checkmark that was already there rather than a
button that appears and disappears, with discard beside it on both the flow
and the dashboard; the brain reveals a neuron's name on the first tap; and the
port sparklines get room to breathe.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VDSXaRhvqHYNevgDGmNAto
Two things from using it. The label only jumped to its new place on
release: its position comes from a memo of ours rather than React Flow's
own store, so nothing moved it until the drag had already finished. It is
now updated on every drag frame, with the write to storage still happening
once at the end rather than once per pixel.
The edges deliberately do not depend on that position — an endpoint's
edges follow from which messages it touches, never from where it sits — so
dragging one no longer rebuilds the edge array on every frame.
And they sit further back at rest, so the nodes read first.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011LF61rxW1FG5YCD2J9YqjY
Three things they were missing: they could not be dragged out of the lane
they were placed in, they stayed the same weight whether or not you were
reaching for one, and the label sat right against its connector dot.
Where one has been dragged to is a view preference, not part of the flow —
writing a position for a dashboard widget into flow.json would be a lie
about what the document holds — so it lives in the browser, keyed by flow.
Also folds the dashboard shot into `make verify` and drops the one-off
scripts that had accumulated beside it; the durable coverage is the
Playwright specs, which all pass.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011LF61rxW1FG5YCD2J9YqjY
Moving a dashboard slider lit up an edge between two nodes that had done
nothing. The canvas pulsed on the message's timestamp alone, and a message
has no idea who published it — so it credited whichever node happened to
be drawn as a producer.
That was never only about dashboards. Two nodes producing one message
pulsed both their edges whichever fired, and a message produced in another
flow changed with nothing on screen to account for it at all.
Values now carry their cause: a node, a dashboard widget, another flow, an
agent or an API caller. An edge pulses only for the producer that actually
published, and the edge inspector says where a value came from when it did
not come from a node.
What is not a node in this flow is now drawn as one — a label rather than
a card, because a dashboard with twenty tiles would otherwise bury the
logic the canvas exists to show. That covers cross-flow wiring too, which
is the link in/out affordance that has been missing.
They are never part of the document. They join at render, after everything
that reads or writes the canvas nodes, so an autosave, an undo or a delete
cannot reach them — with a Playwright test that drags a node and asserts
the stored flow still holds exactly what it did.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011LF61rxW1FG5YCD2J9YqjY