diff --git a/lib/colors.ts b/lib/colors.ts
index 568a1f1..bd469b2 100644
--- a/lib/colors.ts
+++ b/lib/colors.ts
@@ -2,18 +2,9 @@ export const STROKE_REPLACEMENT_COLOR = "#000000";
 export const FILL_REPLACEMENT_COLOR = "#ffffff";
 
 export const TAIL_ATTACHMENT_COLOR = "#ff0000";
-export const LEGS_ATTACHMENT_COLOR = "#ffff00";
-export const ARMS_ATTACHMENT_COLOR = "#00ff00";
-export const HORNS_ATTACHMENT_COLOR = "#00ffff";
+export const LEG_ATTACHMENT_COLOR = "#ffff00";
+export const ARM_ATTACHMENT_COLOR = "#00ff00";
+export const HORN_ATTACHMENT_COLOR = "#00ffff";
 export const CROWN_ATTACHMENT_COLOR = "#0000ff";
 
 export const NESTING_BOUNDING_BOX_COLOR = "#ff00ff";
-
-export const NON_VISUAL_COLORS = new Set([
-  TAIL_ATTACHMENT_COLOR,
-  LEGS_ATTACHMENT_COLOR,
-  ARMS_ATTACHMENT_COLOR,
-  HORNS_ATTACHMENT_COLOR,
-  CROWN_ATTACHMENT_COLOR,
-  NESTING_BOUNDING_BOX_COLOR,
-]);
diff --git a/lib/specs.ts b/lib/specs.ts
new file mode 100644
index 0000000..f676d67
--- /dev/null
+++ b/lib/specs.ts
@@ -0,0 +1,114 @@
+import { Bbox } from "./bounding-box";
+import * as colors from "./colors";
+import type { SvgSymbolElement } from "./vocabulary";
+
+const SPEC_LAYER_ID_RE = /^specs.*/i;
+
+export type Point = {
+  x: number;
+  y: number;
+};
+
+export type Specs = {
+  tail?: Point[];
+  leg?: Point[];
+  arm?: Point[];
+  horn?: Point[];
+  crown?: Point[];
+  nesting?: Bbox[];
+};
+
+function getPoints(path: string): Point[] {
+  // TODO: Implement this.
+  return [];
+}
+
+function getBoundingBoxes(path: string): Bbox[] {
+  // TODO: Implement this.
+  return [];
+}
+
+function concat<T>(first: T[] | undefined, second: T[]): T[] {
+  return first ? [...first, ...second] : second;
+}
+
+function updateSpecs(fill: string, path: string, specs: Specs): Specs {
+  switch (fill) {
+    case colors.TAIL_ATTACHMENT_COLOR:
+      return { ...specs, tail: concat(specs.tail, getPoints(path)) };
+    case colors.LEG_ATTACHMENT_COLOR:
+      return { ...specs, leg: concat(specs.leg, getPoints(path)) };
+    case colors.ARM_ATTACHMENT_COLOR:
+      return { ...specs, arm: concat(specs.arm, getPoints(path)) };
+    case colors.HORN_ATTACHMENT_COLOR:
+      return { ...specs, horn: concat(specs.horn, getPoints(path)) };
+    case colors.CROWN_ATTACHMENT_COLOR:
+      return { ...specs, crown: concat(specs.crown, getPoints(path)) };
+    case colors.NESTING_BOUNDING_BOX_COLOR:
+      return {
+        ...specs,
+        nesting: concat(specs.nesting, getBoundingBoxes(path)),
+      };
+  }
+
+  throw new Error(`Not sure what to do with specs path with fill "${fill}"!`);
+}
+
+function getSpecs(layers: SvgSymbolElement[]): Specs {
+  let specs: Specs = {};
+
+  for (let layer of layers) {
+    if (layer.tagName !== "path") {
+      throw new Error(
+        `Found an unexpected <${layer.tagName}> in the specs layer!`
+      );
+    }
+    const { fill, d } = layer.props;
+    if (!(fill && d)) {
+      throw new Error(
+        `Specs layer does not contain 'fill' and/or 'd' attributes!`
+      );
+    }
+    specs = updateSpecs(fill, d, specs);
+  }
+
+  return specs;
+}
+
+export function extractSpecs(
+  layers: SvgSymbolElement[]
+): [Specs | undefined, SvgSymbolElement[]] {
+  const layersWithoutSpecs: SvgSymbolElement[] = [];
+  let specs: Specs | undefined = undefined;
+
+  const setSpecs = (s: Specs | undefined) => {
+    if (s) {
+      if (specs) {
+        throw new Error("Duplicate specs layers found!");
+      }
+      specs = s;
+    }
+  };
+
+  for (let layer of layers) {
+    switch (layer.tagName) {
+      case "g":
+        const { id } = layer.props;
+        if (id && SPEC_LAYER_ID_RE.test(id)) {
+          setSpecs(getSpecs(layer.children));
+        } else {
+          let [s, children] = extractSpecs(layer.children);
+          setSpecs(s);
+          layersWithoutSpecs.push({
+            ...layer,
+            children,
+          });
+        }
+        break;
+      case "path":
+        layersWithoutSpecs.push(layer);
+    }
+  }
+
+  return [specs, layersWithoutSpecs];
+}
diff --git a/lib/vocabulary.ts b/lib/vocabulary.ts
index 5a8a230..d738be8 100644
--- a/lib/vocabulary.ts
+++ b/lib/vocabulary.ts
@@ -3,11 +3,13 @@ import path from "path";
 import cheerio from "cheerio";
 import { SVGProps } from "react";
 import { getSvgBoundingBox, Bbox } from "./bounding-box";
+import { Specs, extractSpecs } from "./specs";
 
 export type SvgSymbolData = {
   name: string;
   bbox: Bbox;
   layers: SvgSymbolElement[];
+  specs?: Specs;
 };
 
 export type SvgSymbolElement = (
@@ -112,15 +114,17 @@ export function build() {
       const $ = cheerio.load(svgMarkup);
       const svgEl = $("svg");
       const name = path.basename(filename, SVG_EXT);
-      const layers = onlyTags(svgEl.children()).map((ch) =>
+      const rawLayers = onlyTags(svgEl.children()).map((ch) =>
         serializeSvgSymbolElement($, ch)
       );
+      const [specs, layers] = extractSpecs(rawLayers);
       const bbox = getSvgBoundingBox(layers);
 
       const symbol: SvgSymbolData = {
         name,
         bbox,
         layers,
+        specs,
       };
       vocab.push(symbol);
     }