diff --git a/Cargo.lock b/Cargo.lock
index 768d827..268a3f8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3904,7 +3904,7 @@ dependencies = [
 
 [[package]]
 name = "rcalc"
-version = "0.1.25"
+version = "0.1.28"
 dependencies = [
  "slint",
  "slint-build",
diff --git a/Cargo.toml b/Cargo.toml
index 7c9e55d..78b3d3b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "rcalc"
-version = "0.1.25"
+version = "0.1.28"
 edition = "2021"
 build = "build.rs"
 
diff --git a/build.rs b/build.rs
index d7c37fe..d1f9e75 100644
--- a/build.rs
+++ b/build.rs
@@ -1,7 +1,4 @@
 use std::env;
-use std::fs;
-use std::path::PathBuf;
-use std::time::Duration;
 
 fn main() {
     let version = resolve_app_version();
@@ -38,82 +35,10 @@ fn embed_windows_icon() {
 
 /// Window / package version shown as `Rcalc-{version}`.
 ///
-/// On each `release` build the patch in `Cargo.toml` is incremented once
-/// (`0.1.0` → `0.1.1` → …). If Cargo restarts the build script right after we
-/// rewrite `Cargo.toml`, a short mtime guard prevents a double bump.
+/// Always the version from `Cargo.toml`. Раньше каждая release-сборка
+/// инкрементировала patch в Cargo.toml посреди сборки — из-за этого
+/// имя AppImage (читается скриптом до сборки) отставало от версии,
+/// зашитой в бинарник. Теперь версия меняется только вручную.
 fn resolve_app_version() -> String {
-    let manifest_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
-    let pkg = env::var("CARGO_PKG_VERSION").unwrap_or_else(|_| "0.0.0".into());
-    let profile = env::var("PROFILE").unwrap_or_default();
-
-    if profile != "release" {
-        return pkg;
-    }
-
-    let cargo_toml = manifest_dir.join("Cargo.toml");
-    let guard_path = manifest_dir.join(".rcalc_last_bump");
-    let already = fs::read_to_string(&guard_path)
-        .map(|s| s.trim().to_string())
-        .unwrap_or_default();
-
-    // Cargo re-invoked us because we just rewrote Cargo.toml — keep version.
-    if already == pkg {
-        if let Ok(meta) = fs::metadata(&cargo_toml) {
-            if let Ok(modified) = meta.modified() {
-                if modified.elapsed().unwrap_or(Duration::MAX) < Duration::from_secs(15) {
-                    return pkg;
-                }
-            }
-        }
-    }
-
-    let Some(next) = bump_patch(&pkg) else {
-        return pkg;
-    };
-
-    if let Err(e) = set_cargo_toml_version(&cargo_toml, &next) {
-        println!("cargo:warning=could not bump Cargo.toml version: {e}");
-        return pkg;
-    }
-    let _ = fs::write(&guard_path, &next);
-    next
-}
-
-fn bump_patch(version: &str) -> Option<String> {
-    let mut parts: Vec<&str> = version.split('.').collect();
-    if parts.is_empty() {
-        return None;
-    }
-    while parts.len() < 3 {
-        parts.push("0");
-    }
-    let patch: u64 = parts[2]
-        .split(['-', '+'])
-        .next()?
-        .parse()
-        .ok()?;
-    Some(format!("{}.{}.{}", parts[0], parts[1], patch + 1))
-}
-
-fn set_cargo_toml_version(path: &PathBuf, version: &str) -> std::io::Result<()> {
-    let raw = fs::read_to_string(path)?;
-    let mut out = String::with_capacity(raw.len() + 8);
-    let mut replaced = false;
-    for line in raw.lines() {
-        if !replaced && line.starts_with("version") && line.contains('=') {
-            out.push_str(&format!("version = \"{version}\""));
-            out.push('\n');
-            replaced = true;
-        } else {
-            out.push_str(line);
-            out.push('\n');
-        }
-    }
-    if !replaced {
-        return Err(std::io::Error::new(
-            std::io::ErrorKind::InvalidData,
-            "version field not found in Cargo.toml",
-        ));
-    }
-    fs::write(path, out)
+    env::var("CARGO_PKG_VERSION").unwrap_or_else(|_| "0.0.0".into())
 }
diff --git a/dist/rcalc b/dist/rcalc
index 71faa5c..93b60c4 100755
Binary files a/dist/rcalc and b/dist/rcalc differ
diff --git a/scripts/build-appimage.sh b/scripts/build-appimage.sh
index 84b1c3a..ca195ee 100755
--- a/scripts/build-appimage.sh
+++ b/scripts/build-appimage.sh
@@ -101,6 +101,9 @@ package_appimage() {
   echo "Bundling libraries with linuxdeploy…"
   export APPIMAGE_EXTRACT_AND_RUN=1
   export OUTPUT="${IMAGE_NAME}"
+  # Marker: mtime boundary to find the FRESH linuxdeploy output.
+  local marker="${OUT_DIR}/.pack-start"
+  touch "${marker}"
   (
     cd "${OUT_DIR}"
     "${linuxdeploy}" \
@@ -111,11 +114,15 @@ package_appimage() {
       --output appimage
   )
 
-  # linuxdeploy drops the AppImage next to AppDir (dist/)
+  # linuxdeploy drops the AppImage next to AppDir (dist/). Only consider files
+  # NEWER than the marker: a blind `find | head -1` with several older
+  # *.AppImage in dist/ renamed an OLD image OVER the freshly built one
+  # (rcalc-0.1.28 got shipped with a 0.1.25 binary from the first build).
   local built
-  built="$(find "${OUT_DIR}" -maxdepth 1 -name '*.AppImage' ! -name 'linuxdeploy*' | head -1)"
+  built="$(find "${OUT_DIR}" -maxdepth 1 -name '*.AppImage' ! -name 'linuxdeploy*' -newer "${marker}" | head -1)"
+  rm -f "${marker}"
   if [[ -z "$built" ]]; then
-    echo "error: AppImage was not produced" >&2
+    echo "error: AppImage was not produced (linuxdeploy failed?)" >&2
     exit 1
   fi
   if [[ "$(basename "$built")" != "${IMAGE_NAME}" ]]; then
diff --git a/src/engineering.rs b/src/engineering.rs
index 680e5ce..7100516 100644
--- a/src/engineering.rs
+++ b/src/engineering.rs
@@ -389,6 +389,26 @@ impl Engineering {
         self.sync_expr();
     }
 
+    /// Insert `× 10 ^` for scientific-notation entry: `1.5 [×10ˣ] 3 = 1500`.
+    /// Exponent may be negated with ± before `=` (`10 ^ −3` parses correctly).
+    pub fn mul_pow10(&mut self) {
+        if self.error.is_some() {
+            return;
+        }
+        if self.done {
+            // Continue from the result: 1500 [×10ˣ] 2 = 150000.
+            self.formula.clear();
+            self.done = false;
+            self.typing = true;
+        }
+        self.flush_entry();
+        self.formula.push_str(" × 10 ^ ");
+        self.entry = "0".into();
+        self.typing = false;
+        self.second = false;
+        self.sync_expr();
+    }
+
     pub fn equals(&mut self) {
         if self.error.is_some() {
             return;
@@ -884,6 +904,47 @@ mod tests {
         assert_eq!(e.display(), "1024");
     }
 
+    #[test]
+    fn mul_pow10_basic() {
+        // 1.5 ×10ˣ 3 = 1500 (× 10 ^ с приоритетом ^ над ×).
+        let mut e = Engineering::new();
+        e.input_digit('1');
+        e.input_dot();
+        e.input_digit('5');
+        e.mul_pow10();
+        e.input_digit('3');
+        e.equals();
+        assert_eq!(e.display(), "1500");
+    }
+
+    #[test]
+    fn mul_pow10_negative_exponent() {
+        // 2.5 ×10ˣ ±2 = 0.025.
+        let mut e = Engineering::new();
+        e.input_digit('2');
+        e.input_dot();
+        e.input_digit('5');
+        e.mul_pow10();
+        e.input_digit('2');
+        e.negate();
+        e.equals();
+        assert_eq!(e.display(), "0.025");
+    }
+
+    #[test]
+    fn mul_pow10_continues_result() {
+        // 2 × 3 = 6, затем 6 ×10ˣ 2 = 600.
+        let mut e = Engineering::new();
+        e.input_digit('2');
+        e.set_op("×");
+        e.input_digit('3');
+        e.equals();
+        e.mul_pow10();
+        e.input_digit('2');
+        e.equals();
+        assert_eq!(e.display(), "600");
+    }
+
     #[test]
     fn ten_pow_negative_not_zero() {
         // 10 ^ −50 ≈ 1e-50 was snapped to "0" by format_num.
diff --git a/src/main.rs b/src/main.rs
index 82e7c5e..55a651e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -532,6 +532,7 @@ fn handle_engineering(calc: &mut Engineering, id: &str) {
         "eng:fact" => calc.insert_func("fact"),
         "eng:exp" => calc.insert_func("exp"),
         "eng:tenpow" => calc.insert_func("tenpow"),
+        "eng:mul10pow" => calc.mul_pow10(),
         "eng:log" => calc.insert_func("log"),
         "eng:ln" => calc.insert_func("ln"),
         "MC" => calc.memory_clear(),
diff --git a/ui/app.slint b/ui/app.slint
index 0f8865c..f1d0b7f 100644
--- a/ui/app.slint
+++ b/ui/app.slint
@@ -1211,7 +1211,7 @@ export component AppWindow inherits Window {
                     label: root.eng-second ? "³√x" : "√x";
                     clicked => { root.press(root.eng-second ? "eng:cbrt" : "eng:sqrt"); }
                 }
-                FuncBtn { min-h: UiStyle.btn-h-sm; label: "÷"; clicked => { root.press("/"); } }
+                FuncBtn { min-h: UiStyle.btn-h-sm; label: "x*10^y"; clicked => { root.press("eng:mul10pow"); } }
             }
             Row {
                 FuncBtn {
@@ -1222,14 +1222,14 @@ export component AppWindow inherits Window {
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "1/x"; clicked => { root.press("eng:inv"); } }
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "|x|"; clicked => { root.press("eng:abs"); } }
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "n!"; clicked => { root.press("eng:fact"); } }
-                FuncBtn { min-h: UiStyle.btn-h-sm; label: "×"; clicked => { root.press("*"); } }
+                FuncBtn { min-h: UiStyle.btn-h-sm; label: "÷"; clicked => { root.press("/"); } }
             }
             Row {
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "x^y"; clicked => { root.press("^"); } }
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "("; clicked => { root.press("("); } }
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: ")"; clicked => { root.press(")"); } }
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "CE"; clicked => { root.press("CE"); } }
-                FuncBtn { min-h: UiStyle.btn-h-sm; label: "−"; clicked => { root.press("-"); } }
+                FuncBtn { min-h: UiStyle.btn-h-sm; label: "×"; clicked => { root.press("*"); } }
             }
             Row {
                 FuncBtn {
@@ -1240,28 +1240,28 @@ export component AppWindow inherits Window {
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "7"; clicked => { root.press("7"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "8"; clicked => { root.press("8"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "9"; clicked => { root.press("9"); } }
-                FuncBtn { min-h: UiStyle.btn-h-sm; label: "+"; clicked => { root.press("+"); } }
+                FuncBtn { min-h: UiStyle.btn-h-sm; label: "−"; clicked => { root.press("-"); } }
             }
             Row {
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "log"; clicked => { root.press("eng:log"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "4"; clicked => { root.press("4"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "5"; clicked => { root.press("5"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "6"; clicked => { root.press("6"); } }
-                DigitBtn { min-h: UiStyle.btn-h-sm; label: "±"; clicked => { root.press("neg"); } }
+                FuncBtn { min-h: UiStyle.btn-h-sm; label: "+"; clicked => { root.press("+"); } }
             }
             Row {
                 FuncBtn { min-h: UiStyle.btn-h-sm; label: "ln"; clicked => { root.press("eng:ln"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "1"; clicked => { root.press("1"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "2"; clicked => { root.press("2"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "3"; clicked => { root.press("3"); } }
-                EqBtn { min-h: UiStyle.btn-h-sm; clicked => { root.press("="); } }
+                DigitBtn { min-h: UiStyle.btn-h-sm; label: "±"; clicked => { root.press("neg"); } }
             }
             Row {
+                FuncBtn { min-h: UiStyle.btn-h-sm; label: "exp"; clicked => { root.press("eng:exp"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "0"; clicked => { root.press("0"); } }
                 DigitBtn { min-h: UiStyle.btn-h-sm; label: "."; clicked => { root.press("."); } }
-                FuncBtn { min-h: UiStyle.btn-h-sm; label: "exp"; clicked => { root.press("eng:exp"); } }
-                Rectangle { min-height: 32px; background: transparent; }
                 Rectangle { min-height: 32px; background: transparent; }
+                EqBtn { min-h: UiStyle.btn-h-sm; clicked => { root.press("="); } }
             }
         }
 
@@ -1293,10 +1293,17 @@ export component AppWindow inherits Window {
         if root.mode == 0: GridLayout {
             spacing: 6px;
             Row {
-                if root.std-panel == 0: FuncBtn { label: "%"; clicked => { root.press("%"); } }
-                if root.std-panel == 1: FuncBtn { label: "("; clicked => { root.press("("); } }
-                if root.std-panel == 0: FuncBtn { label: "CE"; clicked => { root.press("CE"); } }
-                if root.std-panel == 1: FuncBtn { label: ")"; clicked => { root.press(")"); } }
+                // `if` внутри Row у GridLayout ломает раскладку Slint
+                // (RepeatedItemTree::grid_layout_input_data) — кнопки теряются.
+                // Поэтому одна кнопка с тернарником вместо пары условных.
+                FuncBtn {
+                    label: root.std-panel == 0 ? "%" : "(";
+                    clicked => { root.press(root.std-panel == 0 ? "%" : "("); }
+                }
+                FuncBtn {
+                    label: root.std-panel == 0 ? "CE" : ")";
+                    clicked => { root.press(root.std-panel == 0 ? "CE" : ")"); }
+                }
                 FuncBtn { label: "C"; clicked => { root.press("C"); } }
                 FuncBtn { label: "⌫"; clicked => { root.press("BS"); } }
             }