Glossary

The ubiquitous language of Marrow. Where several words exist for one concept, the heading is the word to use and Avoid lists the ones that cause confusion. This is a glossary, not a specification — implementation details live in Reference.

The description

Topology: A described network — devices, zones, and links — authored as a YAML document. The source of truth a diagram is compiled from. Avoid: map, graph, drawing, network file

Device: A node in a topology. A thing with an icon that links attach to. Avoid: node (that's the geometric form), host, element, asset

Zone: A named container grouping devices by where they are — a site, building, VLAN, or VPC. May nest via a parent. Avoid: group, cluster, region, area

Tier: A device's rank in the network hierarchy — one of edge, core, distribution, access, endpoint, management. Answers what role it plays, never where it is. Avoid: layer, level, role (role is a separate free-text key)

Link: A connection between two devices, optionally terminating at named ports. Avoid: edge (that's the rendered form), connection, cable, line

Mode: A link's logical function — access, trunk, routed, tunnel, peering, stack. The axis orthogonal to kind; it drives the rendered symbol. Declared, never inferred. Avoid: type, role (a device key), switchport-mode

Trunk: A link mode carrying multiple VLANs (802.1Q). Rendered as a double rail with a VLAN chip. Not to be confused with a layout trunk (an aggregate spine edge). Avoid: uplink (a trunk need not be an uplink)

Tunnel: A link mode for overlays and VPNs, refined by encap (ipsec, gre, vxlan, …). Rendered dashed with a padlock chip. Avoid: VPN in the schema (say mode: tunnel), overlay as a key

LAG: A link aggregation group — members share a lag id and bundle onto one strand labelled with that id; lacp names the control protocol. Orthogonal to mode. Avoid: bond, port-channel/etherchannel as keys (those are the vendor names for it)

Port: The named termination of a link on a device — the part after the first colon in an endpoint. Geometry: it determines where a cable attaches. Avoid: interface (that's documentation, not geometry)

Interface: Documentation of a device's network interface — name, description, VLAN, IP. Appears in the inspector. Distinct from a port. Avoid: port, NIC

Endpoint: The device-id or device-id:Port string on one end of a link. Also the name of a tier — the two never appear in the same sentence in practice. Avoid: terminal, attachment

Hero: The device a diagram is about; the camera features it when the diagram opens. Avoid: focus, root, primary, default node

Status: A declared health value on a device or link — up, down, degraded, planned, unknown. Never polled; always stated in the file. Avoid: state, health, alarm

The compiler

Archetype: The shape family a topology is classified into — zoned, tiered, ring, hub-spoke, mesh, or flat. Determines which placement engine runs. Avoid: layout type, template, style, preset (a preset is a placement implementation, not the classification)

Classification: The act of choosing an archetype from declared structure. Declared structure always outranks inferred shape. Avoid: detection, inference

Placement: Assigning positions to devices. Produces boxes. Avoid: layout (which means the whole pipeline), positioning

Routing: Computing the path a link takes between two placed devices. Produces polylines. Avoid: pathfinding, drawing edges

Tidy: The post-routing pass applying cable-tray discipline — merging same-pair parallels onto one visible run and pulling fan-outs onto shared gutter lanes. Avoid: cleanup, optimization, simplification

Scene: The geometric contract handed to the renderers — boxes, polylines, and port chips. Everything downstream speaks only this. Avoid: model (that's the topology), layout result, output

Port chip: The small marker on a device's edge where a link terminates. Placed collision-free by the layout stage; renderers draw it verbatim. Avoid: connector, anchor, handle, stub

Ghost: A dimmed, dashed stub standing in for a device on another page, linking to it. Keeps cross-page links visible instead of dropping them. Avoid: proxy, placeholder, stub

Diagnostic: A machine-readable error or warning carrying a stable MRW- code, a YAML path, line and column, a snippet, a fix hint, and suggestions. Avoid: message, log, issue, problem

Geometry lint: The check run on the scene before rendering. L1 fails the build, L2 auto-repairs, L3 advises. Avoid: validation (that's the schema stage)

The output

Diagram: A compiled, interactive artifact — one self-contained HTML file, or a multi-page site. Avoid: render, image, export, drawing

Single file: The one-document output shape. Everything inlined. Avoid: standalone, bundle, portable mode

Site: The multi-page output shape produced above the split threshold — overview, zone pages, device pages, inventory, shared assets. Avoid: folder mode, multi-page export

Hero tier / scale tier: The two rendering tiers — SVG for full fidelity, a canvas host when the node count demands it. Chosen by size, visually identical. Avoid: SVG mode / canvas mode (they name the implementation, not the tier)

Runtime: The ~20 KB browser client inlined into every diagram — camera, inspector, spotlight, minimap, search, export. Avoid: viewer, player, app

Chrome: The interface surrounding the diagram — sidebar, inspector, command palette, breadcrumbs, dock. shadcn/ui ported to vanilla CSS and TypeScript. Avoid: UI, shell, frame

Brand: The global identity applied to every diagram from marrow.config.yaml — name, note, logo, links. Never per-topology. Avoid: theme (that's dark/light), watermark (one place the brand appears), backdrop (a removed key)

Icons

Pack: A directory of SVGs plus a manifest.json, discovered automatically under icon-packs/. Avoid: library, set, collection

Icon id: The pack/category/name string identifying one icon. Must exist; never guessed. Avoid: icon name, symbol, shape