build.rs instead of frontend crate features

frontend/Cargo.toml

@@ -14,8 +14,3 @@ wasm-bindgen-test = "0.3.19"
 shared.workspace = true
 zoon.workspace = true
 wellen.workspace = true
-
-[features]
-platform_browser = []
-platform_tauri = []
-

frontend/build.rs

@@ -0,0 +1,22 @@
+use std::env;
+
+// https://doc.rust-lang.org/cargo/reference/build-scripts.html
+
+macro_rules! instruction {
+    ($($arg: tt)*) => {
+        println!($($arg)*)
+    }
+}
+
+// https://github.com/rust-lang/cargo/issues/985
+// macro_rules! warning {
+//     ($($arg: tt)*) => {
+//         instruction!("cargo:warning={}", format!($($arg)*))
+//     }
+// }
+
+fn main() {
+    let default_platform = "BROWSER";
+    let platform = env::var("FASTWAVE_PLATFORM").unwrap_or_else(|_| default_platform.to_owned());
+    instruction!("cargo:rustc-cfg=FASTWAVE_PLATFORM=\"{platform}\"");
+}

frontend/src/controls_panel.rs

@@ -143,10 +143,8 @@ impl ControlsPanel {
                 let hierarchy_and_time_table = hierarchy_and_time_table.clone();
                 Task::start(async move {
                     platform::load_waveform(test_file_name).await;
-                    let (hierarchy, time_table) = join!(
-                        platform::get_hierarchy(),
-                        platform::get_time_table()
-                    );
+                    let (hierarchy, time_table) =
+                        join!(platform::get_hierarchy(), platform::get_time_table());
                     hierarchy_and_time_table.set(Some((Rc::new(hierarchy), Rc::new(time_table))))
                 })
             })

frontend/src/platform.rs

@@ -1,16 +1,16 @@
-#[cfg(feature = "platform_tauri")]
+// @TODO maybe rewrite `FASTWAVE_PLATFORM` to features once it's possible to set them through env vars:
+// https://github.com/rust-lang/cargo/issues/4829
+
+#[cfg(FASTWAVE_PLATFORM = "TAURI")]
 mod tauri;
-#[cfg(feature = "platform_tauri")]
+#[cfg(FASTWAVE_PLATFORM = "TAURI")]
 use tauri as platform;
 
-#[cfg(feature = "platform_browser")]
+#[cfg(FASTWAVE_PLATFORM = "BROWSER")]
 mod browser;
-#[cfg(feature = "platform_browser")]
+#[cfg(FASTWAVE_PLATFORM = "BROWSER")]
 use browser as platform;
 
-#[cfg(all(feature = "platform_tauri", feature = "platform_browser"))]
-compile_error!("feature \"foo\" and feature \"bar\" cannot be enabled at the same time");
-
 pub async fn show_window() {
     platform::show_window().await
 }

frontend/src/platform/browser.rs

@@ -1,7 +1,7 @@
-use zoon::*;
+use shared::wellen_helpers;
 use std::sync::Mutex;
 use wellen::simple::Waveform;
-use shared::wellen_helpers;
+use zoon::*;
 
 #[derive(Default)]
 struct Store {