diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index aa168fe7..5fcf1e67 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,8 +14,10 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
+        rust: [nightly, stable]
 
     runs-on: ${{ matrix.os }}
+    continue-on-error: ${{ matrix.rust == 'nightly' }}
 
     steps:
     - uses: actions/checkout@v2
@@ -23,7 +25,8 @@ jobs:
     - name: Install Rust
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: stable
+        toolchain: ${{ matrix.rust }}
+        default: true
         profile: minimal
         components: clippy
 
diff --git a/asyncgit/src/sync/hunks.rs b/asyncgit/src/sync/hunks.rs
index e0e86dad..99a72de3 100644
--- a/asyncgit/src/sync/hunks.rs
+++ b/asyncgit/src/sync/hunks.rs
@@ -111,7 +111,13 @@ pub fn unstage_hunk(
 
     let diff = get_diff_raw(&repo, &file_path, true, true)?;
 
-    assert_eq!(diff.deltas().len(), diff_count_positive);
+    if diff.deltas().len() != diff_count_positive {
+        return Err(Error::Generic(format!(
+            "hunk error: {}!={}",
+            diff.deltas().len(),
+            diff_count_positive
+        )));
+    }
 
     let mut count = 0;
     {
diff --git a/src/cmdbar.rs b/src/cmdbar.rs
index 4496b00d..26ae7050 100644
--- a/src/cmdbar.rs
+++ b/src/cmdbar.rs
@@ -124,7 +124,7 @@ impl CommandBar {
         self.refresh_list(self.width);
     }
 
-    pub fn height(&self) -> u16 {
+    pub const fn height(&self) -> u16 {
         if self.expandable && self.expanded {
             self.lines
         } else {
diff --git a/src/components/command.rs b/src/components/command.rs
index 8c6a6e07..0f855321 100644
--- a/src/components/command.rs
+++ b/src/components/command.rs
@@ -63,24 +63,28 @@ impl CommandInfo {
             order: 0,
         }
     }
+
     ///
     pub const fn order(self, order: i8) -> Self {
         let mut res = self;
         res.order = order;
         res
     }
+
     ///
     pub const fn hidden(self) -> Self {
         let mut res = self;
         res.quick_bar = false;
         res
     }
+
     ///
     pub fn print(&self, out: &mut String) {
         out.push_str(&self.text.name);
     }
+
     ///
-    pub fn show_in_quickbar(&self) -> bool {
+    pub const fn show_in_quickbar(&self) -> bool {
         self.quick_bar && self.available
     }
 }
diff --git a/src/components/commit.rs b/src/components/commit.rs
index 72ce7cf3..3643a586 100644
--- a/src/components/commit.rs
+++ b/src/components/commit.rs
@@ -208,11 +208,10 @@ impl CommitComponent {
             return Ok(());
         }
 
-        let res = if let Some(amend) = self.amend {
-            sync::amend(CWD, amend, &msg)
-        } else {
-            sync::commit(CWD, &msg)
-        };
+        let res =
+            self.amend.map_or(sync::commit(CWD, &msg), |amend| {
+                sync::amend(CWD, amend, &msg)
+            });
         if let Err(e) = res {
             log::error!("commit error: {}", &e);
             self.queue.borrow_mut().push_back(
diff --git a/src/components/commit_details/details.rs b/src/components/commit_details/details.rs
index 8d15bebd..0ef5c738 100644
--- a/src/components/commit_details/details.rs
+++ b/src/components/commit_details/details.rs
@@ -69,11 +69,8 @@ impl DetailsComponent {
     ) -> Result<()> {
         self.tags.clear();
 
-        self.data = if let Some(id) = id {
-            sync::get_commit_details(CWD, id).ok()
-        } else {
-            None
-        };
+        self.data =
+            id.and_then(|id| sync::get_commit_details(CWD, id).ok());
 
         self.scroll_top.set(0);
 
diff --git a/src/components/commitlist.rs b/src/components/commitlist.rs
index 66cdf663..8608172c 100644
--- a/src/components/commitlist.rs
+++ b/src/components/commitlist.rs
@@ -252,13 +252,11 @@ impl CommitList {
             .take(height)
             .enumerate()
         {
-            let tags = if let Some(tags) =
-                self.tags.as_ref().and_then(|t| t.get(&e.id))
-            {
-                Some(tags.join(" "))
-            } else {
-                None
-            };
+            let tags = self
+                .tags
+                .as_ref()
+                .and_then(|t| t.get(&e.id))
+                .map(|tags| tags.join(" "));
 
             Self::add_entry(
                 e,
diff --git a/src/components/diff.rs b/src/components/diff.rs
index f3387010..e2ea94ec 100644
--- a/src/components/diff.rs
+++ b/src/components/diff.rs
@@ -38,13 +38,13 @@ enum Selection {
 }
 
 impl Selection {
-    fn get_start(&self) -> usize {
+    const fn get_start(&self) -> usize {
         match self {
             Self::Single(start) | Self::Multiple(start, _) => *start,
         }
     }
 
-    fn get_end(&self) -> usize {
+    const fn get_end(&self) -> usize {
         match self {
             Self::Single(end) | Self::Multiple(_, end) => *end,
         }
@@ -447,7 +447,7 @@ impl DiffComponent {
         ));
     }
 
-    fn hunk_visible(
+    const fn hunk_visible(
         hunk_min: usize,
         hunk_max: usize,
         min: usize,
diff --git a/src/components/filetree.rs b/src/components/filetree.rs
index 56a77e5e..8305d0c1 100644
--- a/src/components/filetree.rs
+++ b/src/components/filetree.rs
@@ -113,14 +113,12 @@ impl FileTreeComponent {
 
     ///
     pub fn is_file_seleted(&self) -> bool {
-        if let Some(item) = self.tree.selected_item() {
+        self.tree.selected_item().map_or(false, |item| {
             match item.kind {
                 FileTreeItemKind::File(_) => true,
                 FileTreeItemKind::Path(..) => false,
             }
-        } else {
-            false
-        }
+        })
     }
 
     fn move_selection(&mut self, dir: MoveSelection) -> bool {
@@ -207,7 +205,7 @@ impl FileTreeComponent {
         }
     }
 
-    fn item_status_char(item_type: StatusItemType) -> char {
+    const fn item_status_char(item_type: StatusItemType) -> char {
         match item_type {
             StatusItemType::Modified => 'M',
             StatusItemType::New => '+',
diff --git a/src/components/textinput.rs b/src/components/textinput.rs
index 651a3f7e..36a2ad42 100644
--- a/src/components/textinput.rs
+++ b/src/components/textinput.rs
@@ -122,14 +122,11 @@ impl TextInputComponent {
             ));
         }
 
-        let cursor_str = if let Some(pos) = self.next_char_position()
-        {
-            &self.msg[self.cursor_position..pos]
-        } else {
+        let cursor_str = self
+            .next_char_position()
             // if the cursor is at the end of the msg
             // a whitespace is used to underline
-            " "
-        };
+            .map_or(" ", |pos| &self.msg[self.cursor_position..pos]);
 
         if cursor_str == "\n" {
             txt.push(Text::styled(
diff --git a/src/components/utils/statustree.rs b/src/components/utils/statustree.rs
index 1c930385..a5c6049a 100644
--- a/src/components/utils/statustree.rs
+++ b/src/components/utils/statustree.rs
@@ -44,17 +44,16 @@ impl StatusTree {
         let last_selection_index = self.selection.unwrap_or(0);
 
         self.tree = FileTreeItems::new(list, &last_collapsed)?;
-        self.selection =
-            if let Some(ref last_selection) = last_selection {
+        self.selection = last_selection.as_ref().map_or(
+            self.tree.items().first().map(|_| 0),
+            |last_selection| {
                 self.find_last_selection(
                     last_selection,
                     last_selection_index,
                 )
                 .or_else(|| self.tree.items().first().map(|_| 0))
-            } else {
-                // simply select first
-                self.tree.items().first().map(|_| 0)
-            };
+            },
+        );
 
         self.update_visibility(None, 0, true);
 
@@ -80,7 +79,7 @@ impl StatusTree {
 
     ///
     pub fn move_selection(&mut self, dir: MoveSelection) -> bool {
-        if let Some(selection) = self.selection {
+        self.selection.map_or(false, |selection| {
             let selection_change = match dir {
                 MoveSelection::Up => {
                     self.selection_updown(selection, true)
@@ -102,9 +101,7 @@ impl StatusTree {
             self.selection = Some(selection_change.new_index);
 
             changed_index || selection_change.changes
-        } else {
-            false
-        }
+        })
     }
 
     ///
diff --git a/src/main.rs b/src/main.rs
index 911ed11f..116a9f4b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -7,6 +7,7 @@
 #![deny(clippy::panic)]
 #![allow(clippy::module_name_repetitions)]
 #![allow(clippy::multiple_crate_versions)]
+#![warn(clippy::missing_const_for_fn)]
 
 mod app;
 mod cmdbar;
diff --git a/src/tabs/revlog.rs b/src/tabs/revlog.rs
index 633e157c..90f85135 100644
--- a/src/tabs/revlog.rs
+++ b/src/tabs/revlog.rs
@@ -158,15 +158,7 @@ impl Revlog {
         let tags = self.list.tags();
 
         commit.and_then(|commit| {
-            if let Some(tags) = tags {
-                if let Some(tags) = tags.get(&commit) {
-                    Some(tags.clone())
-                } else {
-                    None
-                }
-            } else {
-                None
-            }
+            tags.and_then(|tags| tags.get(&commit).cloned())
         })
     }
 }
@@ -213,28 +205,32 @@ impl Component for Revlog {
                     self.update()?;
                     return Ok(true);
                 } else if k == self.key_config.log_tag_commit {
-                    return if let Some(id) = self.selected_commit() {
-                        self.queue
-                            .borrow_mut()
-                            .push_back(InternalEvent::TagCommit(id));
-                        Ok(true)
-                    } else {
-                        Ok(false)
-                    };
+                    return self.selected_commit().map_or(
+                        Ok(false),
+                        |id| {
+                            self.queue.borrow_mut().push_back(
+                                InternalEvent::TagCommit(id),
+                            );
+                            Ok(true)
+                        },
+                    );
                 } else if k == self.key_config.focus_right
                     && self.commit_details.is_visible()
                 {
-                    return if let Some(id) = self.selected_commit() {
-                        self.queue.borrow_mut().push_back(
-                            InternalEvent::InspectCommit(
-                                id,
-                                self.selected_commit_tags(&Some(id)),
-                            ),
-                        );
-                        Ok(true)
-                    } else {
-                        Ok(false)
-                    };
+                    return self.selected_commit().map_or(
+                        Ok(false),
+                        |id| {
+                            self.queue.borrow_mut().push_back(
+                                InternalEvent::InspectCommit(
+                                    id,
+                                    self.selected_commit_tags(&Some(
+                                        id,
+                                    )),
+                                ),
+                            );
+                            Ok(true)
+                        },
+                    );
                 } else {
                 }
             }
diff --git a/src/ui/style.rs b/src/ui/style.rs
index dc632d87..3a33c5ed 100644
--- a/src/ui/style.rs
+++ b/src/ui/style.rs
@@ -116,7 +116,11 @@ impl Theme {
         self.apply_select(style, selected)
     }
 
-    fn apply_select(&self, style: Style, selected: bool) -> Style {
+    const fn apply_select(
+        &self,
+        style: Style,
+        selected: bool,
+    ) -> Style {
         if selected {
             style.bg(self.selection_bg)
         } else {