diff --git a/server/src/gateway.rs b/server/src/gateway.rs
index 18550947..f0051033 100644
--- a/server/src/gateway.rs
+++ b/server/src/gateway.rs
@@ -1634,50 +1634,12 @@ pub async fn gateway_bot_config_page_handler() -> Response {
 
 // ── Gateway server startup ───────────────────────────────────────────
 
-/// Start the gateway HTTP server. This is the entry point when `--gateway` is used.
-pub async fn run(config_path: &Path, port: u16) -> Result<(), std::io::Error> {
-    // Locate the gateway config directory (parent of `projects.toml`).
-    let config_dir = config_path
-        .parent()
-        .unwrap_or(std::path::Path::new("."))
-        .to_path_buf();
-
-    let config = GatewayConfig::load(config_path).map_err(std::io::Error::other)?;
-    let state =
-        GatewayState::new(config, config_dir.clone(), port).map_err(std::io::Error::other)?;
-    let state_arc = Arc::new(state);
-
-    let active = state_arc.active_project.read().await.clone();
-    crate::slog!("[gateway] Starting gateway on port {port}, active project: {active}");
-    crate::slog!(
-        "[gateway] Registered projects: {}",
-        state_arc
-            .projects
-            .read()
-            .await
-            .keys()
-            .cloned()
-            .collect::<Vec<_>>()
-            .join(", ")
-    );
-
-    // Write `.mcp.json` so that the gateway's Matrix bot's Claude Code CLI
-    // connects to this gateway's MCP endpoint (which proxies to the active project).
-    if let Err(e) = write_gateway_mcp_json(&config_dir, port) {
-        crate::slog!("[gateway] Warning: could not write .mcp.json: {e}");
-    }
-
-    // Spawn the Matrix bot if `.huskies/bot.toml` exists in the config directory.
-    let gateway_projects: Vec<String> = state_arc.projects.read().await.keys().cloned().collect();
-    let bot_abort = spawn_gateway_bot(
-        &config_dir,
-        Arc::clone(&state_arc.active_project),
-        gateway_projects,
-        port,
-    );
-    *state_arc.bot_handle.lock().await = bot_abort;
-
-    let route = poem::Route::new()
+/// Build the complete gateway route tree.
+///
+/// Extracted from `run` so that tests can construct the full route tree and
+/// catch duplicate-route panics before they reach production.
+pub fn build_gateway_route(state_arc: Arc<GatewayState>) -> impl poem::Endpoint {
+    poem::Route::new()
         .at("/bot-config", poem::get(gateway_bot_config_page_handler))
         .at("/api/gateway", poem::get(gateway_api_handler))
         .at("/api/gateway/switch", poem::post(gateway_switch_handler))
@@ -1732,7 +1694,53 @@ pub async fn run(config_path: &Path, port: u16) -> Result<(), std::io::Error> {
         )
         .at("/*path", poem::get(crate::http::assets::embedded_file))
         .at("/", poem::get(crate::http::assets::embedded_index))
-        .data(state_arc);
+        .data(state_arc)
+}
+
+/// Start the gateway HTTP server. This is the entry point when `--gateway` is used.
+pub async fn run(config_path: &Path, port: u16) -> Result<(), std::io::Error> {
+    // Locate the gateway config directory (parent of `projects.toml`).
+    let config_dir = config_path
+        .parent()
+        .unwrap_or(std::path::Path::new("."))
+        .to_path_buf();
+
+    let config = GatewayConfig::load(config_path).map_err(std::io::Error::other)?;
+    let state =
+        GatewayState::new(config, config_dir.clone(), port).map_err(std::io::Error::other)?;
+    let state_arc = Arc::new(state);
+
+    let active = state_arc.active_project.read().await.clone();
+    crate::slog!("[gateway] Starting gateway on port {port}, active project: {active}");
+    crate::slog!(
+        "[gateway] Registered projects: {}",
+        state_arc
+            .projects
+            .read()
+            .await
+            .keys()
+            .cloned()
+            .collect::<Vec<_>>()
+            .join(", ")
+    );
+
+    // Write `.mcp.json` so that the gateway's Matrix bot's Claude Code CLI
+    // connects to this gateway's MCP endpoint (which proxies to the active project).
+    if let Err(e) = write_gateway_mcp_json(&config_dir, port) {
+        crate::slog!("[gateway] Warning: could not write .mcp.json: {e}");
+    }
+
+    // Spawn the Matrix bot if `.huskies/bot.toml` exists in the config directory.
+    let gateway_projects: Vec<String> = state_arc.projects.read().await.keys().cloned().collect();
+    let bot_abort = spawn_gateway_bot(
+        &config_dir,
+        Arc::clone(&state_arc.active_project),
+        gateway_projects,
+        port,
+    );
+    *state_arc.bot_handle.lock().await = bot_abort;
+
+    let route = build_gateway_route(state_arc);
 
     let host = std::env::var("HUSKIES_HOST").unwrap_or_else(|_| "127.0.0.1".to_string());
     let addr = format!("{host}:{port}");
@@ -2260,4 +2268,16 @@ enabled = false
             .await;
         assert_eq!(resp.0.status(), StatusCode::NOT_FOUND);
     }
+
+    /// Build the full gateway route tree and verify it does not panic.
+    ///
+    /// Poem panics at construction time when duplicate routes are registered.
+    /// This test catches any regression where a duplicate route is re-introduced
+    /// (e.g. the `/` vs `/*path` duplicate fixed in commit 0969fb5d).
+    #[test]
+    fn gateway_route_tree_builds_without_panic() {
+        let state = make_test_state();
+        // build_gateway_route will panic if any route is registered more than once.
+        let _route = build_gateway_route(state);
+    }
 }