diff --git a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/generated/leaflet-ais-tracksymbol.js b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/generated/leaflet-ais-tracksymbol.js
index b46ec68e..32f73063 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/generated/leaflet-ais-tracksymbol.js
+++ b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/generated/leaflet-ais-tracksymbol.js
@@ -1,94 +1,98 @@
 "use strict";
-(function() {
-  if (typeof L === "undefined") return;
-  function clamp(value, min, max) {
-    return Math.max(min, Math.min(max, value));
-  }
-  function finiteAngle(value) {
-    if (!Number.isFinite(value)) return null;
-    const normalized = (Number(value) % 360 + 360) % 360;
-    return normalized;
-  }
-  function svgColor(value, fallback) {
-    const text = String(value || fallback || "");
-    return text.replace(/"/g, """);
-  }
-  function buildSymbolHtml(options, zoom) {
-    const heading = finiteAngle(options.heading);
-    const course = finiteAngle(options.course);
-    const angle = heading != null ? heading : course;
-    const speed = Number.isFinite(options.speed) ? Math.max(0, Number(options.speed)) : 0;
-    const sizeBase = Number.isFinite(options.size) ? Number(options.size) : 22;
-    const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
-    const size = clamp(sizeBase + zoomBoost, 16, 32);
-    const courseLen = course != null ? clamp(size * (0.55 + Math.min(speed, 30) / 30), size * 0.55, size * 1.2) : 0;
-    const color = svgColor(options.color, "#ff7559");
-    const outline = svgColor(options.outline, "#6b2118");
-    const body = angle != null ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${angle}) translate(${-size / 2} ${-size / 2})"><path d="M ${size * 0.5} ${size * 0.06} L ${size * 0.82} ${size * 0.78} L ${size * 0.5} ${size * 0.62} L ${size * 0.18} ${size * 0.78} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" /></g>` : `<path d="M ${size * 0.5} ${size * 0.12} L ${size * 0.88} ${size * 0.5} L ${size * 0.5} ${size * 0.88} L ${size * 0.12} ${size * 0.5} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" />`;
-    const courseLine = course != null ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${course})"><line x1="0" y1="${-size * 0.22}" x2="0" y2="${-(size * 0.22 + courseLen)}" stroke="${color}" stroke-width="1.4" stroke-linecap="round" opacity="0.75" /></g>` : "";
-    return `<svg xmlns="http://www.w3.org/2000/svg" width="${size}" height="${size}" viewBox="0 0 ${size} ${size}" aria-hidden="true">` + courseLine + body + `</svg>`;
-  }
-  L.TrxAisTrackSymbol = L.Marker.extend({
-    options: {
-      heading: null,
-      course: null,
-      speed: null,
-      color: "#ff7559",
-      outline: "#6b2118",
-      size: 22,
-      interactive: true,
-      keyboard: true,
-      riseOnHover: true
-    },
-    initialize: function(latlng, options) {
-      const merged = L.Util.extend({}, this.options, options || {});
-      merged.icon = L.divIcon({
-        className: "trx-ais-track-symbol-icon",
-        html: "",
-        iconSize: [merged.size, merged.size],
-        iconAnchor: [merged.size / 2, merged.size / 2]
-      });
-      L.Marker.prototype.initialize.call(this, latlng, merged);
-    },
-    onAdd: function(map) {
-      L.Marker.prototype.onAdd.call(this, map);
-      this._refreshIcon();
-      this._boundZoomRefresh = this._refreshIcon.bind(this);
-      map.on("zoomend", this._boundZoomRefresh);
-    },
-    onRemove: function(map) {
-      if (this._boundZoomRefresh) {
-        map.off("zoomend", this._boundZoomRefresh);
-        this._boundZoomRefresh = null;
-      }
-      L.Marker.prototype.onRemove.call(this, map);
-    },
-    setAisState: function(next) {
-      if (next && typeof next === "object") {
+(() => {
+  // src/leaflet-ais-tracksymbol.ts
+  (function() {
+    const leaflet = globalThis.L;
+    if (!leaflet) return;
+    function clamp(value, min, max) {
+      return Math.max(min, Math.min(max, value));
+    }
+    function finiteAngle(value) {
+      if (value === null || !Number.isFinite(value)) return null;
+      const normalized = (value % 360 + 360) % 360;
+      return normalized;
+    }
+    function svgColor(value, fallback) {
+      const text = value || fallback || "";
+      return text.replace(/"/g, "&quot;");
+    }
+    function buildSymbolHtml(options, zoom) {
+      const heading = finiteAngle(options.heading);
+      const course = finiteAngle(options.course);
+      const angle = heading != null ? heading : course;
+      const speed = Number.isFinite(options.speed) ? Math.max(0, Number(options.speed)) : 0;
+      const sizeBase = Number.isFinite(options.size) ? options.size : 22;
+      const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
+      const size = clamp(sizeBase + zoomBoost, 16, 32);
+      const courseLen = course != null ? clamp(size * (0.55 + Math.min(speed, 30) / 30), size * 0.55, size * 1.2) : 0;
+      const color = svgColor(options.color, "#ff7559");
+      const outline = svgColor(options.outline, "#6b2118");
+      const body = angle != null ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${angle}) translate(${-size / 2} ${-size / 2})"><path d="M ${size * 0.5} ${size * 0.06} L ${size * 0.82} ${size * 0.78} L ${size * 0.5} ${size * 0.62} L ${size * 0.18} ${size * 0.78} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" /></g>` : `<path d="M ${size * 0.5} ${size * 0.12} L ${size * 0.88} ${size * 0.5} L ${size * 0.5} ${size * 0.88} L ${size * 0.12} ${size * 0.5} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" />`;
+      const courseLine = course != null ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${course})"><line x1="0" y1="${-size * 0.22}" x2="0" y2="${-(size * 0.22 + courseLen)}" stroke="${color}" stroke-width="1.4" stroke-linecap="round" opacity="0.75" /></g>` : "";
+      return `<svg xmlns="http://www.w3.org/2000/svg" width="${size}" height="${size}" viewBox="0 0 ${size} ${size}" aria-hidden="true">` + courseLine + body + `</svg>`;
+    }
+    leaflet.TrxAisTrackSymbol = leaflet.Marker.extend({
+      options: {
+        heading: null,
+        course: null,
+        speed: null,
+        color: "#ff7559",
+        outline: "#6b2118",
+        size: 22,
+        interactive: true,
+        keyboard: true,
+        riseOnHover: true
+      },
+      initialize: function(latlng, options) {
+        const merged = leaflet.Util.extend({}, this.options, options || {});
+        merged.icon = leaflet.divIcon({
+          className: "trx-ais-track-symbol-icon",
+          html: "",
+          iconSize: [merged.size, merged.size],
+          iconAnchor: [merged.size / 2, merged.size / 2]
+        });
+        leaflet.Marker.prototype.initialize.call(this, latlng, merged);
+      },
+      onAdd: function(map) {
+        leaflet.Marker.prototype.onAdd.call(this, map);
+        this._refreshIcon();
+        this._boundZoomRefresh = this._refreshIcon.bind(this);
+        map.on("zoomend", this._boundZoomRefresh);
+      },
+      onRemove: function(map) {
+        if (this._boundZoomRefresh) {
+          map.off("zoomend", this._boundZoomRefresh);
+          this._boundZoomRefresh = null;
+        }
+        leaflet.Marker.prototype.onRemove.call(this, map);
+      },
+      setAisState: function(next) {
         if ("heading" in next) this.options.heading = next.heading;
         if ("course" in next) this.options.course = next.course;
         if ("speed" in next) this.options.speed = next.speed;
         if ("color" in next) this.options.color = next.color;
         if ("outline" in next) this.options.outline = next.outline;
+        this._refreshIcon();
+        return this;
+      },
+      _refreshIcon: function() {
+        if (!this._icon) return;
+        const zoom = this._map && typeof this._map.getZoom === "function" ? this._map.getZoom() : 0;
+        const html = buildSymbolHtml(this.options, zoom);
+        this._icon.innerHTML = html;
+        const sizeBase = Number.isFinite(this.options.size) ? this.options.size : 22;
+        const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
+        const size = clamp(sizeBase + zoomBoost, 16, 32);
+        this._icon.style.width = `${size}px`;
+        this._icon.style.height = `${size}px`;
+        this._icon.style.marginLeft = `${-size / 2}px`;
+        this._icon.style.marginTop = `${-size / 2}px`;
       }
-      this._refreshIcon();
-      return this;
-    },
-    _refreshIcon: function() {
-      if (!this._icon) return;
-      const zoom = this._map && typeof this._map.getZoom === "function" ? this._map.getZoom() : 0;
-      const html = buildSymbolHtml(this.options, zoom);
-      this._icon.innerHTML = html;
-      const sizeBase = Number.isFinite(this.options.size) ? Number(this.options.size) : 22;
-      const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
-      const size = clamp(sizeBase + zoomBoost, 16, 32);
-      this._icon.style.width = `${size}px`;
-      this._icon.style.height = `${size}px`;
-      this._icon.style.marginLeft = `${-size / 2}px`;
-      this._icon.style.marginTop = `${-size / 2}px`;
-    }
-  });
-  L.trxAisTrackSymbol = function(latlng, options) {
-    return new L.TrxAisTrackSymbol(latlng, options);
-  };
+    });
+    leaflet.trxAisTrackSymbol = function(latlng, options) {
+      const Constructor = leaflet.TrxAisTrackSymbol;
+      if (!Constructor) throw new Error("AIS track symbol constructor is unavailable");
+      return new Constructor(latlng, options);
+    };
+  })();
 })();
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/frontend/build.mjs b/src/trx-client/trx-frontend/trx-frontend-http/frontend/build.mjs
index c73bd27f..0cb620bb 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/frontend/build.mjs
+++ b/src/trx-client/trx-frontend/trx-frontend-http/frontend/build.mjs
@@ -21,7 +21,6 @@ await build({
     "map-core": path.join(sourceDir, "map-core.js"),
     screenshot: path.join(sourceDir, "screenshot.ts"),
     "webgl-renderer": path.join(sourceDir, "webgl-renderer.ts"),
-    "leaflet-ais-tracksymbol": path.join(sourceDir, "leaflet-ais-tracksymbol.js"),
     ais: path.join(sourceDir, "plugins", "ais.js"),
     aprs: path.join(sourceDir, "plugins", "aprs.js"),
     "background-decode": path.join(sourceDir, "plugins", "background-decode.js"),
@@ -50,6 +49,7 @@ await build({
     wspr: path.join(sourceDir, "plugins", "wspr.ts"),
     cw: path.join(sourceDir, "plugins", "cw.ts"),
     ft8: path.join(sourceDir, "plugins", "ft8.ts"),
+    "leaflet-ais-tracksymbol": path.join(sourceDir, "leaflet-ais-tracksymbol.ts"),
   },
   outdir: outputDir,
   bundle: true,
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/frontend/eslint.config.js b/src/trx-client/trx-frontend/trx-frontend-http/frontend/eslint.config.js
index 4b367188..13f1783c 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/frontend/eslint.config.js
+++ b/src/trx-client/trx-frontend/trx-frontend-http/frontend/eslint.config.js
@@ -37,6 +37,7 @@ export default tseslint.config(
     rules: {
       "no-undef": "off",
       "@typescript-eslint/no-explicit-any": "error",
+      "@typescript-eslint/restrict-template-expressions": ["error", { allowNumber: true }],
     },
   },
 );
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/frontend/src/leaflet-ais-tracksymbol.js b/src/trx-client/trx-frontend/trx-frontend-http/frontend/src/leaflet-ais-tracksymbol.js
deleted file mode 100644
index ad0d13b3..00000000
--- a/src/trx-client/trx-frontend/trx-frontend-http/frontend/src/leaflet-ais-tracksymbol.js
+++ /dev/null
@@ -1,120 +0,0 @@
-(function() {
-  if (typeof L === "undefined") return;
-
-  function clamp(value, min, max) {
-    return Math.max(min, Math.min(max, value));
-  }
-
-  function finiteAngle(value) {
-    if (!Number.isFinite(value)) return null;
-    const normalized = ((Number(value) % 360) + 360) % 360;
-    return normalized;
-  }
-
-  function svgColor(value, fallback) {
-    const text = String(value || fallback || "");
-    return text.replace(/"/g, "&quot;");
-  }
-
-  function buildSymbolHtml(options, zoom) {
-    const heading = finiteAngle(options.heading);
-    const course = finiteAngle(options.course);
-    const angle = heading != null ? heading : course;
-    const speed = Number.isFinite(options.speed) ? Math.max(0, Number(options.speed)) : 0;
-    const sizeBase = Number.isFinite(options.size) ? Number(options.size) : 22;
-    const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
-    const size = clamp(sizeBase + zoomBoost, 16, 32);
-    const courseLen = course != null ? clamp(size * (0.55 + Math.min(speed, 30) / 30), size * 0.55, size * 1.2) : 0;
-    const color = svgColor(options.color, "#ff7559");
-    const outline = svgColor(options.outline, "#6b2118");
-
-    const body = angle != null
-      ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${angle}) translate(${-size / 2} ${-size / 2})">` +
-          `<path d="M ${size * 0.5} ${size * 0.06} L ${size * 0.82} ${size * 0.78} L ${size * 0.5} ${size * 0.62} L ${size * 0.18} ${size * 0.78} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" />` +
-        `</g>`
-      : `<path d="M ${size * 0.5} ${size * 0.12} L ${size * 0.88} ${size * 0.5} L ${size * 0.5} ${size * 0.88} L ${size * 0.12} ${size * 0.5} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" />`;
-
-    const courseLine = course != null
-      ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${course})">` +
-          `<line x1="0" y1="${-size * 0.22}" x2="0" y2="${-(size * 0.22 + courseLen)}" stroke="${color}" stroke-width="1.4" stroke-linecap="round" opacity="0.75" />` +
-        `</g>`
-      : "";
-
-    return (
-      `<svg xmlns="http://www.w3.org/2000/svg" width="${size}" height="${size}" viewBox="0 0 ${size} ${size}" aria-hidden="true">` +
-        courseLine +
-        body +
-      `</svg>`
-    );
-  }
-
-  L.TrxAisTrackSymbol = L.Marker.extend({
-    options: {
-      heading: null,
-      course: null,
-      speed: null,
-      color: "#ff7559",
-      outline: "#6b2118",
-      size: 22,
-      interactive: true,
-      keyboard: true,
-      riseOnHover: true,
-    },
-
-    initialize: function(latlng, options) {
-      const merged = L.Util.extend({}, this.options, options || {});
-      merged.icon = L.divIcon({
-        className: "trx-ais-track-symbol-icon",
-        html: "",
-        iconSize: [merged.size, merged.size],
-        iconAnchor: [merged.size / 2, merged.size / 2],
-      });
-      L.Marker.prototype.initialize.call(this, latlng, merged);
-    },
-
-    onAdd: function(map) {
-      L.Marker.prototype.onAdd.call(this, map);
-      this._refreshIcon();
-      this._boundZoomRefresh = this._refreshIcon.bind(this);
-      map.on("zoomend", this._boundZoomRefresh);
-    },
-
-    onRemove: function(map) {
-      if (this._boundZoomRefresh) {
-        map.off("zoomend", this._boundZoomRefresh);
-        this._boundZoomRefresh = null;
-      }
-      L.Marker.prototype.onRemove.call(this, map);
-    },
-
-    setAisState: function(next) {
-      if (next && typeof next === "object") {
-        if ("heading" in next) this.options.heading = next.heading;
-        if ("course" in next) this.options.course = next.course;
-        if ("speed" in next) this.options.speed = next.speed;
-        if ("color" in next) this.options.color = next.color;
-        if ("outline" in next) this.options.outline = next.outline;
-      }
-      this._refreshIcon();
-      return this;
-    },
-
-    _refreshIcon: function() {
-      if (!this._icon) return;
-      const zoom = this._map && typeof this._map.getZoom === "function" ? this._map.getZoom() : 0;
-      const html = buildSymbolHtml(this.options, zoom);
-      this._icon.innerHTML = html;
-      const sizeBase = Number.isFinite(this.options.size) ? Number(this.options.size) : 22;
-      const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
-      const size = clamp(sizeBase + zoomBoost, 16, 32);
-      this._icon.style.width = `${size}px`;
-      this._icon.style.height = `${size}px`;
-      this._icon.style.marginLeft = `${-size / 2}px`;
-      this._icon.style.marginTop = `${-size / 2}px`;
-    },
-  });
-
-  L.trxAisTrackSymbol = function(latlng, options) {
-    return new L.TrxAisTrackSymbol(latlng, options);
-  };
-})();
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/frontend/src/leaflet-ais-tracksymbol.ts b/src/trx-client/trx-frontend/trx-frontend-http/frontend/src/leaflet-ais-tracksymbol.ts
new file mode 100644
index 00000000..a2c04e03
--- /dev/null
+++ b/src/trx-client/trx-frontend/trx-frontend-http/frontend/src/leaflet-ais-tracksymbol.ts
@@ -0,0 +1,163 @@
+// SPDX-FileCopyrightText: 2026 Stan Grams <sjg@haxx.space>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+export {};
+
+interface AisSymbolOptions {
+  heading: number | null;
+  course: number | null;
+  speed: number | null;
+  color: string;
+  outline: string;
+  size: number;
+  interactive: boolean;
+  keyboard: boolean;
+  riseOnHover: boolean;
+  icon?: unknown;
+}
+interface LeafletMapAdapter { on(event: string, listener: () => void): void; off(event: string, listener: () => void): void; getZoom(): number }
+interface TrackSymbolInstance {
+  options: AisSymbolOptions;
+  _icon?: HTMLElement;
+  _map?: LeafletMapAdapter;
+  _boundZoomRefresh?: (() => void) | null;
+  _refreshIcon(): void;
+}
+interface TrackSymbolConstructor { new(latlng: unknown, options?: Partial<AisSymbolOptions>): TrackSymbolInstance }
+interface LeafletAdapter {
+  Marker: {
+    extend(definition: object & ThisType<TrackSymbolInstance>): TrackSymbolConstructor;
+    prototype: {
+      initialize(this: TrackSymbolInstance, latlng: unknown, options: AisSymbolOptions): void;
+      onAdd(this: TrackSymbolInstance, map: LeafletMapAdapter): void;
+      onRemove(this: TrackSymbolInstance, map: LeafletMapAdapter): void;
+    };
+  };
+  Util: { extend<T extends object>(target: T, ...sources: object[]): T };
+  divIcon(options: object): unknown;
+  TrxAisTrackSymbol?: TrackSymbolConstructor;
+  trxAisTrackSymbol?: (latlng: unknown, options?: Partial<AisSymbolOptions>) => TrackSymbolInstance;
+}
+
+(function() {
+  const leaflet = (globalThis as unknown as { L?: LeafletAdapter }).L;
+  if (!leaflet) return;
+
+  function clamp(value: number, min: number, max: number): number {
+    return Math.max(min, Math.min(max, value));
+  }
+
+  function finiteAngle(value: number | null): number | null {
+    if (value === null || !Number.isFinite(value)) return null;
+    const normalized = ((value % 360) + 360) % 360;
+    return normalized;
+  }
+
+  function svgColor(value: string, fallback: string): string {
+    const text = value || fallback || "";
+    return text.replace(/"/g, "&quot;");
+  }
+
+  function buildSymbolHtml(options: AisSymbolOptions, zoom: number): string {
+    const heading = finiteAngle(options.heading);
+    const course = finiteAngle(options.course);
+    const angle = heading != null ? heading : course;
+    const speed = Number.isFinite(options.speed) ? Math.max(0, Number(options.speed)) : 0;
+    const sizeBase = Number.isFinite(options.size) ? options.size : 22;
+    const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
+    const size = clamp(sizeBase + zoomBoost, 16, 32);
+    const courseLen = course != null ? clamp(size * (0.55 + Math.min(speed, 30) / 30), size * 0.55, size * 1.2) : 0;
+    const color = svgColor(options.color, "#ff7559");
+    const outline = svgColor(options.outline, "#6b2118");
+
+    const body = angle != null
+      ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${angle}) translate(${-size / 2} ${-size / 2})">` +
+          `<path d="M ${size * 0.5} ${size * 0.06} L ${size * 0.82} ${size * 0.78} L ${size * 0.5} ${size * 0.62} L ${size * 0.18} ${size * 0.78} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" />` +
+        `</g>`
+      : `<path d="M ${size * 0.5} ${size * 0.12} L ${size * 0.88} ${size * 0.5} L ${size * 0.5} ${size * 0.88} L ${size * 0.12} ${size * 0.5} Z" fill="${color}" stroke="${outline}" stroke-width="1.2" stroke-linejoin="round" />`;
+
+    const courseLine = course != null
+      ? `<g transform="translate(${size / 2} ${size / 2}) rotate(${course})">` +
+          `<line x1="0" y1="${-size * 0.22}" x2="0" y2="${-(size * 0.22 + courseLen)}" stroke="${color}" stroke-width="1.4" stroke-linecap="round" opacity="0.75" />` +
+        `</g>`
+      : "";
+
+    return (
+      `<svg xmlns="http://www.w3.org/2000/svg" width="${size}" height="${size}" viewBox="0 0 ${size} ${size}" aria-hidden="true">` +
+        courseLine +
+        body +
+      `</svg>`
+    );
+  }
+
+  leaflet.TrxAisTrackSymbol = leaflet.Marker.extend({
+    options: {
+      heading: null,
+      course: null,
+      speed: null,
+      color: "#ff7559",
+      outline: "#6b2118",
+      size: 22,
+      interactive: true,
+      keyboard: true,
+      riseOnHover: true,
+    },
+
+    initialize: function(latlng: unknown, options?: Partial<AisSymbolOptions>) {
+      const merged = leaflet.Util.extend({} as AisSymbolOptions, this.options, options || {});
+      merged.icon = leaflet.divIcon({
+        className: "trx-ais-track-symbol-icon",
+        html: "",
+        iconSize: [merged.size, merged.size],
+        iconAnchor: [merged.size / 2, merged.size / 2],
+      });
+      leaflet.Marker.prototype.initialize.call(this, latlng, merged);
+    },
+
+    onAdd: function(map: LeafletMapAdapter) {
+      leaflet.Marker.prototype.onAdd.call(this, map);
+      this._refreshIcon();
+      this._boundZoomRefresh = this._refreshIcon.bind(this);
+      map.on("zoomend", this._boundZoomRefresh);
+    },
+
+    onRemove: function(map: LeafletMapAdapter) {
+      if (this._boundZoomRefresh) {
+        map.off("zoomend", this._boundZoomRefresh);
+        this._boundZoomRefresh = null;
+      }
+      leaflet.Marker.prototype.onRemove.call(this, map);
+    },
+
+    setAisState: function(next: Partial<AisSymbolOptions>) {
+      if ("heading" in next) this.options.heading = next.heading;
+      if ("course" in next) this.options.course = next.course;
+      if ("speed" in next) this.options.speed = next.speed;
+      if ("color" in next) this.options.color = next.color;
+      if ("outline" in next) this.options.outline = next.outline;
+      this._refreshIcon();
+      return this;
+    },
+
+    _refreshIcon: function() {
+      if (!this._icon) return;
+      const zoom = this._map && typeof this._map.getZoom === "function" ? this._map.getZoom() : 0;
+      const html = buildSymbolHtml(this.options, zoom);
+      this._icon.innerHTML = html;
+      const sizeBase = Number.isFinite(this.options.size) ? this.options.size : 22;
+      const zoomBoost = zoom >= 12 ? 4 : zoom >= 9 ? 2 : 0;
+      const size = clamp(sizeBase + zoomBoost, 16, 32);
+      this._icon.style.width = `${size}px`;
+      this._icon.style.height = `${size}px`;
+      this._icon.style.marginLeft = `${-size / 2}px`;
+      this._icon.style.marginTop = `${-size / 2}px`;
+    },
+  });
+
+  leaflet.trxAisTrackSymbol = function(latlng: unknown, options?: Partial<AisSymbolOptions>) {
+    const Constructor = leaflet.TrxAisTrackSymbol;
+    if (!Constructor) throw new Error("AIS track symbol constructor is unavailable");
+    return new Constructor(latlng, options);
+  };
+})();
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/leaflet-ais-tracksymbol.test.mjs b/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/leaflet-ais-tracksymbol.test.mjs
new file mode 100644
index 00000000..46ccbda6
--- /dev/null
+++ b/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/leaflet-ais-tracksymbol.test.mjs
@@ -0,0 +1,58 @@
+// SPDX-FileCopyrightText: 2026 Stan Grams <sjg@haxx.space>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+import assert from "node:assert/strict";
+import { readFile } from "node:fs/promises";
+import test from "node:test";
+import vm from "node:vm";
+
+test("local AIS track-symbol adapter renders immediately on first add", async () => {
+  const listeners = new Map();
+  const map = {
+    getZoom: () => 10,
+    on: (event, listener) => { listeners.set(event, listener); },
+    off: (event) => { listeners.delete(event); },
+  };
+  const markerPrototype = {
+    initialize(_latlng, options) { this.options = options; },
+    onAdd(addedMap) { this._map = addedMap; this._icon = { innerHTML: "", style: {} }; },
+    onRemove() { this._map = null; },
+  };
+  const L = {
+    Marker: {
+      prototype: markerPrototype,
+      extend(definition) {
+        return class TrackSymbol {
+          constructor(latlng, options) {
+            this.options = { ...definition.options };
+            definition.initialize.call(this, latlng, options);
+          }
+        };
+      },
+    },
+    Util: { extend: Object.assign },
+    divIcon: (options) => options,
+  };
+  const source = await readFile(
+    new URL("../../assets/web/generated/leaflet-ais-tracksymbol.js", import.meta.url),
+    "utf8",
+  );
+  new vm.Script(source).runInNewContext({ L, console });
+  Object.assign(L.TrxAisTrackSymbol.prototype, {
+    onAdd: markerPrototype.onAdd,
+    onRemove: markerPrototype.onRemove,
+  });
+  // The fake `extend` above only models construction; copy plugin methods from
+  // a second extend capture so the test exercises the generated adapter.
+  let definition;
+  L.Marker.extend = (value) => { definition = value; return L.TrxAisTrackSymbol; };
+  new vm.Script(source).runInNewContext({ L, console });
+  Object.assign(L.TrxAisTrackSymbol.prototype, definition);
+
+  const symbol = L.trxAisTrackSymbol([52, 21], { heading: 90, speed: 12 });
+  symbol.onAdd(map);
+  assert.match(symbol._icon.innerHTML, /<svg/);
+  assert.match(symbol._icon.innerHTML, /rotate\(90\)/);
+  assert.equal(listeners.has("zoomend"), true);
+});