diff --git a/web/root/src/bus.ts b/web/root/src/bus.ts
index 351e6e8..1c56cd0 100644
--- a/web/root/src/bus.ts
+++ b/web/root/src/bus.ts
@@ -1,6 +1,7 @@
 // deno-lint-ignore-file
 
 import type { Machine } from "./automata.ts";
+import type { Example } from "./examples.ts";
 import type { Sim, SimStepResult } from "./simulation.ts";
 import type wasm from "./wasm.ts";
 import type { Text } from "npm:@codemirror/state";
@@ -73,13 +74,16 @@ type AppEvents = {
   "automata/sim/after_step": { simulation: Sim, result: SimStepResult };
   "automata/update": { automaton: Machine };
 
-  "controls/physics": {enabled: boolean},
-  "controls/reset_network": void,
-  
+  "example/selected": {example: Example};
 
-  "controls/step_simulation": void,
-  "controls/reload_simulation": void,
-  "controls/clear_simulation": void,
+  "controls/editor/set_text": {text: string};
+  
+  "controls/vis/physics": {enabled: boolean};
+  "controls/vis/reset_network": void;
+  
+  "controls/sim/step": void;
+  "controls/sim/reload": void;
+  "controls/sim/clear": void;
 
   "theme/update": void;
 };
diff --git a/web/root/src/controls.ts b/web/root/src/controls.ts
index ef8a8c0..16980f3 100644
--- a/web/root/src/controls.ts
+++ b/web/root/src/controls.ts
@@ -15,59 +15,6 @@ const speedLabel = document.getElementById("speedSimLabel") as HTMLSpanElement;
 const reloadSimBtn = document.getElementById("reloadSim") as HTMLButtonElement;
 const clearSimBtn = document.getElementById("clearSim") as HTMLButtonElement;
 
-bus.on("controls/physics", ({ enabled }) => {
-  togglePhysicsBtn.classList.toggle("active", enabled);
-  togglePhysicsBtn.textContent = enabled ? "Physics: ON" : "Physics: OFF";
-});
-
-togglePhysicsBtn.onclick = () => {
-  const enabled = !togglePhysicsBtn.classList.contains("active");
-  bus.emit("controls/physics", { enabled });
-};
-
-bus.emit("controls/physics", {
-  enabled: togglePhysicsBtn.classList.contains("active"),
-});
-
-resetLayoutBtn.onclick = () => bus.emit("controls/reset_network", undefined);
-
-clearSimBtn.onclick = () => bus.emit("controls/clear_simulation", undefined);
-
-stepBtn.onclick = () => {
-  bus.emit("controls/step_simulation", undefined);
-};
-
-reloadSimBtn.onclick = () => bus.emit("controls/reload_simulation", undefined);
-
-function updateButtons() {
-  stepBtn.disabled = !simulation_active || running;
-  playPauseBtn.disabled = !simulation_active;
-  clearSimBtn.disabled = !simulation_active;
-}
-
-bus.on("controls/reload_simulation", (_) => {
-  if (running) setRunning(false);
-  updateButtons();
-});
-
-bus.on("automata/sim/update", ({ simulation }) => {
-  simulation_active = !!simulation;
-  if (!simulation) {
-    if (running) setRunning(false);
-  }
-  updateButtons();
-});
-
-bus.on("automata/sim/after_step", ({ result }) => {
-  if (result !== "pending") {
-    if (running) setRunning(false);
-  }
-});
-
-let simulation_active = false;
-let running = false;
-let timer: number | null = null;
-
 // speed slider is "steps per second"
 function getStepsPerSecond() {
   return Math.max(1, Math.min(60, Number(speedSlider.value) || 10));
@@ -77,39 +24,82 @@ function updateSpeedUI() {
 }
 updateSpeedUI();
 
-speedSlider.addEventListener("input", () => {
-  updateSpeedUI();
-  if (running) restartTimer();
-});
+class Controls {
+  static simulation_active = false;
+  static running = false;
+  static timer: number | null = null;
 
-function stopTimer() {
-  if (timer !== null) {
-    clearInterval(timer);
-    timer = null;
+  static updateButtons() {
+    stepBtn.disabled = !Controls.simulation_active || Controls.running;
+    playPauseBtn.disabled = !Controls.simulation_active;
+    clearSimBtn.disabled = !Controls.simulation_active;
+  }
+  static setRunning(on: boolean) {
+    Controls.running = on;
+    playPauseBtn.textContent = Controls.running ? "⏸ Pause" : "▶ Play";
+    playPauseBtn.classList.toggle("btn-primary", !Controls.running);
+    playPauseBtn.classList.toggle("btn-secondary", Controls.running);
+
+    if (Controls.running) Controls.restartTimer();
+    else Controls.stopTimer();
+    Controls.updateButtons();
+  }
+  static stop() {
+    if (Controls.running) Controls.setRunning(false);
+  }
+  static stopTimer() {
+    if (Controls.timer !== null) {
+      clearInterval(Controls.timer);
+      Controls.timer = null;
+    }
+  }
+
+  static restartTimer() {
+    Controls.stopTimer();
+    const sps = getStepsPerSecond();
+    const intervalMs = Math.round(1000 / sps);
+
+    Controls.timer = globalThis.window.setInterval(() => {
+      bus.emit("controls/sim/step", undefined);
+    }, intervalMs);
+  }
+
+  static {
+    speedSlider.addEventListener("input", () => {
+      updateSpeedUI();
+      if (Controls.running) Controls.restartTimer();
+    });
+    playPauseBtn.onclick = () => Controls.setRunning(!Controls.running);
+    resetLayoutBtn.onclick = () =>
+      bus.emit("controls/vis/reset_network", undefined);
+    clearSimBtn.onclick = () => bus.emit("controls/sim/clear", undefined);
+    stepBtn.onclick = () => bus.emit("controls/sim/step", undefined);
+    reloadSimBtn.onclick = () => bus.emit("controls/sim/reload", undefined);
+    togglePhysicsBtn.onclick = () => {
+      const enabled = !togglePhysicsBtn.classList.contains("active");
+      bus.emit("controls/vis/physics", { enabled });
+    };
+
+    bus.on("controls/vis/physics", ({ enabled }) => {
+      togglePhysicsBtn.classList.toggle("active", enabled);
+      togglePhysicsBtn.textContent = enabled ? "Physics: ON" : "Physics: OFF";
+    });
+
+    bus.on("controls/sim/reload", (_) => {
+      if (Controls.running) Controls.setRunning(false);
+    });
+
+    bus.on("automata/sim/update", ({ simulation }) => {
+      Controls.simulation_active = !!simulation;
+      if (!simulation) Controls.stop();
+    });
+
+    bus.on("automata/sim/after_step", ({ result }) => {
+      if (result !== "pending") Controls.stop();
+    });
+
+    bus.emit("controls/vis/physics", {
+      enabled: togglePhysicsBtn.classList.contains("active"),
+    });
   }
 }
-
-function restartTimer() {
-  stopTimer();
-  const sps = getStepsPerSecond();
-  const intervalMs = Math.round(1000 / sps);
-
-  timer = globalThis.window.setInterval(() => {
-    bus.emit("controls/step_simulation", undefined);
-  }, intervalMs);
-}
-
-function setRunning(on: boolean) {
-  running = on;
-  playPauseBtn.textContent = running ? "⏸ Pause" : "▶ Play";
-  playPauseBtn.classList.toggle("btn-primary", !running);
-  playPauseBtn.classList.toggle("btn-secondary", running);
-
-  // Disable step while running (optional, but feels nice)
-  stepBtn.disabled = running;
-
-  if (running) restartTimer();
-  else stopTimer();
-}
-
-playPauseBtn.onclick = () => setRunning(!running);
diff --git a/web/root/src/editor.ts b/web/root/src/editor.ts
index e9d925f..d3594be 100644
--- a/web/root/src/editor.ts
+++ b/web/root/src/editor.ts
@@ -1,67 +1,71 @@
 // deno-lint-ignore-file
 
 import {
-  EditorView,
-  keymap,
-  hoverTooltip,
   Decoration,
-  lineNumbers,
+  EditorView,
+  highlightActiveLine,
   highlightActiveLineGutter,
-  highlightActiveLine
+  hoverTooltip,
+  keymap,
+  lineNumbers,
 } from "npm:@codemirror/view";
 
 import { EditorState, StateField, Text } from "npm:@codemirror/state";
-import { defaultKeymap, history, historyKeymap } from "npm:@codemirror/commands";
+import {
+  defaultKeymap,
+  history,
+  historyKeymap,
+} from "npm:@codemirror/commands";
 import { bracketMatching, indentOnInput } from "npm:@codemirror/language";
 import { closeBrackets } from "npm:@codemirror/autocomplete";
 
+import wasm from "./wasm.ts";
 
-import wasm from "./wasm.ts"
-
-import { sharedText } from "./share.ts";
+import { Share } from "./share.ts";
 import { examples } from "./examples.ts";
 import { bus } from "./bus.ts";
 
-
-function tokenize(text: string) {
+function tokenize(text: string): wasm.Tok[] {
   try {
     return wasm.lex(text);
   } catch (e) {
-    console.log(e)
-    return []
+    console.log(e);
+    return [];
   }
 }
 
-function compile(text: string): wasm.CompileResult {
+function compile(
+  text: string,
+): { log: wasm.CompileLog[]; ansi_log: string; machine: string | undefined } {
   try {
     return wasm.compile(text);
   } catch (e) {
     console.log(e);
-    // @ts-expect-error wasm defines extra cleanup 
-    return {log: [], log_formatted: "", graph: ""};
+    return { log: [], ansi_log: "", machine: "" };
   }
 }
 
 const eventBusConnection = StateField.define({
   create(state) {
     const text = state.doc.toString();
-    bus.emit("editor/change", {text, doc: state.doc});
+    bus.emit("editor/change", { text, doc: state.doc });
     return buildAnalysis(text, state.doc);
   },
   update(value, tr) {
     if (!tr.docChanged) return value;
     const text = tr.state.doc.toString();
-    bus.emit("editor/change", {text, doc: state.doc});
+    bus.emit("editor/change", { text, doc: state.doc });
     return buildAnalysis(text, tr.state.doc);
   },
   provide: (f) => EditorView.decorations.from(f, (v) => v.deco),
 });
 
 function buildAnalysis(text: string, doc: Text) {
+  save(text);
   const tokens = tokenize(text);
   const { log, ansi_log, machine } = compile(text);
 
-  bus.emit("compiled", {log, ansi_log, machine})
+  bus.emit("compiled", { log, ansi_log, machine });
 
   const marks = [];
   const docLen = doc.length;
@@ -88,7 +92,9 @@ function buildAnalysis(text: string, doc: Text) {
       marks.push(Decoration.mark({ class: cls }).range(start, end));
     } else {
       const end = Math.min(docLen, start + 1);
-      if (end > start) marks.push(Decoration.mark({ class: cls }).range(start, end));
+      if (end > start) {
+        marks.push(Decoration.mark({ class: cls }).range(start, end));
+      }
     }
   }
 
@@ -96,8 +102,7 @@ function buildAnalysis(text: string, doc: Text) {
   return { tokens, log, ansi_log, deco };
 }
 
-const tokenClass = (t: string) =>
-({
+const tokenClass = (t: string) => ({
   comment: "tok-comment",
   keyword: "tok-keyword",
   error: "tok-error",
@@ -113,7 +118,6 @@ const tokenClass = (t: string) =>
   rbracket: "rb-",
 }[t] || "tok-ident");
 
-
 function severityClass(sev: string) {
   const s = (sev || "error").toLowerCase();
   if (s === "warning") return "cm-diag-warning";
@@ -129,10 +133,16 @@ function sevRank(sev: string) {
 // ===================== Hover tooltip (uses cached diags) =====================
 const diagHover = hoverTooltip((view, pos) => {
   const { log } = view.state.field(eventBusConnection);
-  const hits = log.filter((d) => d.start !== undefined && d.end !== undefined && pos >= d.start && pos <= d.end);
+  const hits = log.filter((d) =>
+    d.start !== undefined && d.end !== undefined && pos >= d.start &&
+    pos <= d.end
+  );
   if (hits.length === 0) return null;
 
-  const top = hits.reduce((a, b) => (sevRank(b.level) > sevRank(a.level) ? b : a), hits[0]);
+  const top = hits.reduce(
+    (a, b) => (sevRank(b.level) > sevRank(a.level) ? b : a),
+    hits[0],
+  );
 
   return {
     pos,
@@ -144,8 +154,9 @@ const diagHover = hoverTooltip((view, pos) => {
 
       const title = document.createElement("div");
       title.className = `tipTitle ${top.level}`;
-      title.textContent =
-        hits.length === 1 ? top.level.toUpperCase() : `${top.level.toUpperCase()} (${hits.length})`;
+      title.textContent = hits.length === 1
+        ? top.level.toUpperCase()
+        : `${top.level.toUpperCase()} (${hits.length})`;
 
       const body = document.createElement("div");
       body.className = "tipBody";
@@ -162,24 +173,20 @@ const diagHover = hoverTooltip((view, pos) => {
   };
 });
 
-function save(text: string){
+function save(text: string) {
   globalThis.localStorage.save = text;
 }
 
-function getSaved(): string | undefined{
+function getSaved(): string | undefined {
   return globalThis.localStorage.save;
 }
 
-export function setText(text: string){
-  editor.dispatch({ changes: { from: 0, to: editor.state.doc.length, insert: text } });
-}
-
-export function getText(): string{
-  return editor.state.doc.toString()
+function defaultText(): string {
+  return Share.sharedText() ?? getSaved() ?? examples[0].machine;
 }
 
 const state = EditorState.create({
-  doc: "",
+  doc: defaultText(),
   extensions: [
     lineNumbers(),
     highlightActiveLineGutter(),
@@ -202,4 +209,17 @@ const editor = new EditorView({
   parent: document.getElementById("editor")!,
 });
 
-bus.on("begin", _ => setText(sharedText() ?? getSaved() ?? examples[0].machine))
\ No newline at end of file
+bus.on(
+  "begin",
+  (_) => bus.emit("controls/editor/set_text", { text: defaultText() }),
+);
+
+bus.on("controls/editor/set_text", ({ text }) => {
+  editor.dispatch({
+    changes: { from: 0, to: editor.state.doc.length, insert: text },
+  });
+});
+
+bus.on("example/selected", ({ example }) => {
+  bus.emit("controls/editor/set_text", { text: example.machine });
+});
diff --git a/web/root/src/examples.ts b/web/root/src/examples.ts
index eb9234b..6745845 100644
--- a/web/root/src/examples.ts
+++ b/web/root/src/examples.ts
@@ -1,4 +1,4 @@
-import { setText } from "./editor.ts";
+import { bus } from "./bus.ts";
 
 export type Category =
   | "Tutorial"
@@ -241,6 +241,6 @@ function buildExamplesDropdown(
 }
 
 const selectEl = document.getElementById("exampleSelect") as HTMLSelectElement;
-buildExamplesDropdown(selectEl, examples, (picked) => {
-  setText(picked.machine);
+buildExamplesDropdown(selectEl, examples, (example) => {
+  bus.emit("example/selected", {example});
 });
diff --git a/web/root/src/share.ts b/web/root/src/share.ts
index d9eaba4..715b3ce 100644
--- a/web/root/src/share.ts
+++ b/web/root/src/share.ts
@@ -1,41 +1,49 @@
-import { getText } from "./editor.ts";
+import { bus } from "./bus.ts";
 
-const btn = document.getElementById("shareBtn")!;
-const toast = document.getElementById("shareToast")!;
+export class Share {
+  private static readonly btn: HTMLButtonElement = document.getElementById(
+    "shareBtn",
+  )! as HTMLButtonElement;
+  private static readonly toast: HTMLElement = document.getElementById(
+    "shareToast",
+  )!;
 
-function generateShareLink() {
-  return `${globalThis.window.location.href}?share=${encodeURIComponent(btoa(getText()))}`;
-}
+  private static docText: string;
+  private static shareText: string;
 
-async function copy(text: string) {
-  await navigator.clipboard.writeText(text);
-}
+  static {
+    bus.on("editor/change", ({ text }) => Share.docText = text);
 
-btn.addEventListener("click", async () => {
-  await copy(generateShareLink());
+    Share.btn.onclick = async (_) => {
+      const link = `${globalThis.window.location.href}?share=${
+        encodeURIComponent(btoa(Share.docText))
+      }`;
+      await navigator.clipboard.writeText(link);
 
-  toast.classList.remove("show");
-  void toast.offsetWidth; 
-  toast.classList.add("show");
-});
+      Share.toast.classList.remove("show");
+      void Share.toast.offsetWidth;
+      Share.toast.classList.add("show");
+    };
 
-
-export function sharedText(): string|null {
-  try{
-    const url = new URL(globalThis.window.location.href);
-    let text: string | null = url.searchParams.get("share");
-    if (text !== null) {
-      text = atob(text);
-      url.searchParams.delete("share");
-      globalThis.window.history.replaceState(
-        {},
-        document.title,
-        url.pathname + url.search + url.hash
-      );
+    try {
+      const url = new URL(globalThis.window.location.href);
+      let text: string | null = url.searchParams.get("share");
+      if (text !== null) {
+        text = atob(text);
+        url.searchParams.delete("share");
+        globalThis.window.history.replaceState(
+          {},
+          document.title,
+          url.pathname + url.search + url.hash,
+        );
+        Share.shareText = text;
+      }
+    } catch (e) {
+      console.log(e);
     }
-    return text;
-  }catch(e){
-    console.log(e)
   }
-  return null;
-}
\ No newline at end of file
+
+  public static sharedText(): string | null {
+    return Share.shareText;
+  }
+}
diff --git a/web/root/src/simulation.ts b/web/root/src/simulation.ts
index 083885f..7e78a02 100644
--- a/web/root/src/simulation.ts
+++ b/web/root/src/simulation.ts
@@ -1,13 +1,13 @@
 import { bus } from "./bus.ts";
-import {
+import type {
   Fa,
   Machine,
-  parse_machine_from_json,
   Pda,
   State,
   Symbol,
   Tm,
 } from "./automata.ts";
+import {parse_machine_from_json} from "./automata.ts";
 
 export type SimStepResult = "pending" | "accept" | "reject";
 export type Sim = FaSim | PdaSim | TmSim;
@@ -26,7 +26,7 @@ let automaton: Machine = {
 bus.on("compiled", ({ machine }) => {
   if (machine) {
     try {
-      bus.emit("controls/clear_simulation", undefined);
+      bus.emit("controls/sim/clear", undefined);
       automaton = parse_machine_from_json(machine);
       bus.emit("automata/update", { automaton });
     } catch (e) {
@@ -34,11 +34,11 @@ bus.on("compiled", ({ machine }) => {
     }
   }
 });
-bus.on("controls/clear_simulation", (_) => {
+bus.on("controls/sim/clear", (_) => {
   simulation = null;
   bus.emit("automata/sim/update", { simulation: null });
 });
-bus.on("controls/step_simulation", (_) => {
+bus.on("controls/sim/step", (_) => {
   if (simulation) {
     bus.emit("automata/sim/before_step", { simulation });
     bus.emit("automata/sim/after_step", {
@@ -51,10 +51,10 @@ const machineInput = document.getElementById("machineInput") as HTMLInputElement
 machineInput.addEventListener("input", () => bus.emit("automata/sim/update", {simulation: null}));
 machineInput.addEventListener("keydown", (e) => {
   if (e.key === "Enter") {
-    bus.emit("controls/reload_simulation", undefined)
+    bus.emit("controls/sim/reload", undefined)
   }
 });
-bus.on("controls/reload_simulation", (_) => {
+bus.on("controls/sim/reload", (_) => {
   const input = machineInput.value;
   switch (automaton.type) {
     case "fa":
diff --git a/web/root/src/visualizer.ts b/web/root/src/visualizer.ts
index 8c34b15..0c4bae0 100644
--- a/web/root/src/visualizer.ts
+++ b/web/root/src/visualizer.ts
@@ -7,11 +7,11 @@ import type { Sim } from "./simulation.ts";
 import type { Machine } from "./automata.ts";
 
 
-bus.on("controls/physics", ({enabled}) => {
+bus.on("controls/vis/physics", ({enabled}) => {
   network.setOptions({ physics: { enabled } });
   network.setOptions({edges: {smooth: enabled}});
 });
-bus.on("controls/reset_network", _ => {
+bus.on("controls/vis/reset_network", _ => {
     try {
         nodes.forEach((n) => {
           n.physics = true;
@@ -285,17 +285,16 @@ function createGraph(): vis.Network {
       nodes: {
         shape: "custom",
         size: 18,
-        // // @ts-expect-error  bad library
-        // chosen: {
-        //   node: chosen_node,
-        // },
         // @ts-expect-error  bad library
+        chosen: {
+          node: chosen_node,
+        },
         ctxRenderer: renderNode,
       },
       edges: {
         chosen: {
-          // // @ts-expect-error bad library
-          // edge: chosen_edge,
+          // @ts-expect-error bad library
+          edge: chosen_edge,
         },
         arrowStrikethrough: false,
         arrows: "to",
@@ -304,9 +303,8 @@ function createGraph(): vis.Network {
   );
   vis.DataSet;
 
-  network.on("doubleClick", (params: any) => {
+  network.on("doubleClick", (params: {nodes: string[]}) => {
     for (const node_id of params.nodes) {
-      // @ts-expect-error bad library
       const node: vis.Node = nodes.get(node_id)!;
       node.physics = !node.physics;
       nodes.update(node);
@@ -325,7 +323,7 @@ function renderNode({
   state: { selected, hover },
   style,
   label,
-}: {ctx: CanvasRenderingContext2D, id: string, x: number, y: number, state: {selected: boolean, hover: boolean}, style: any, label: string}) {
+}: {ctx: CanvasRenderingContext2D, id: string, x: number, y: number, state: {selected: boolean, hover: boolean}, style: vis.NodeOptions, label: string}) {
   return {
     drawNode() {
       const t = getGraphTheme();