schemd

@schemd/core · v0.3.3 · MIT

Schematics are
source code.

schemd pronounced like skemd /skɛmd/

We treat a schematic the way a compiler treats source. Write electrical, logic, quantum, and UML diagrams as plain text; the pipeline tokenizes each declaration, validates its options against the component kind you named, routes traces around component bodies, and emits deterministic, accessible SVG — on a server, with zero dependencies.

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npm i @schemd/core
Mixed-signal input stage6 components and 6 connections.VINVinR110 kΩVOUToutput nodeC1100 nFGND0 VOUTVout
Mixed-signal input stage
live · mode=full
nodes
6
wires
6
bytes
19,641
compile
11 ms
// Native source + junction + physically rotated shunt capacitor
source:VIN "V_{in}" at (80, 120) #blue [type=voltage-ac]
resistor:R1 "10 kΩ" at (260, 120) #amber
junction:VOUT "output node" at (440, 120) #cyan
capacitor:C1 "100 nF" at (440, 250) #cyan [orientation=down]
ground:GND "0 V" at (220, 350) #slate
port:OUT "V_{out}" at (680, 120) #emerald

VIN.positive -> R1.in #blue [line]
VIN.negative -> GND.in #slate [ortho]
R1.out -> VOUT.node #amber [line]
VOUT.node -> C1.in #cyan [ortho]
C1.out -> GND.in #cyan [ortho]
VOUT.node -> OUT.in #emerald [line marker-end=arrow]

the pass, end to end

Text in. Vector out. Four deterministic passes.

  1. 01

    Tokenize

    Each declaration is lexed into kind, id, label, coordinate, color, and options.

  2. 02

    Validate

    Options are checked by name against the kind you named — unknowns fail loudly.

  3. 03

    Route

    Orthogonal traces escape each body, avoid every obstacle, and bridge true crossings.

  4. 04

    Emit

    A deterministic, accessible SVG — byte-identical for identical source.

what you get

An engineering compiler, not a drawing toy.

01

Two-line grammar

Components and connections. Everything else is bracketed options, validated by name against the kind you chose — so a typo is an error at compile time, never a silent wrong drawing.

02

Zero dependencies

No DOM, no browser layout pass, no Markdown parser. The compiler runs on a server or during a build — this very page compiled its own hero, four ways.

03

Deterministic output

Identical source yields byte-identical SVG. Diagnostics carry exact one-based line numbers.

04

Obstacle-aware routing

Orthogonal traces route around bodies with clearance; crossings get draftsman bridge arcs, never false junctions.

05

Three output budgets

default stays static; embedded-css adds theme styles; full instruments every node, port, and wire.

06

Bounded by design

Hard ceilings on everything. The writer refuses to exceed them, so a runaway document fails fast instead of exhausting the server.

512
components
2,048
connections
32,768
wire crossings
2 MiB
SVG output