diff --git a/editor/src/lib.rs b/editor/src/lib.rs
index 9df30fe881..ea4d15fdb0 100644
--- a/editor/src/lib.rs
+++ b/editor/src/lib.rs
@@ -79,7 +79,7 @@ fn run_event_loop(file_path_opt: Option<&Path>) -> Result<(), Box<dyn Error>> {
     let event_loop = winit::event_loop::EventLoop::new();
 
     let window = winit::window::WindowBuilder::new()
-        .with_inner_size(PhysicalSize::new(1000.0, 800.0))
+        .with_inner_size(PhysicalSize::new(1200.0, 1000.0))
         .build(&event_loop)
         .unwrap();
 
@@ -384,11 +384,11 @@ fn queue_all_text(
     };
 
     let caret_pos_label = Text {
-        position: (30.0, (size.height as f32) - 45.0).into(),
+        position: ((size.width as f32) - 150.0, (size.height as f32) - 40.0).into(),
         area_bounds,
         color: TXT_COLOR.into(),
         text: format!("Ln {}, Col {}", caret_pos.line, caret_pos.column),
-        size: 30.0,
+        size: 25.0,
         ..Default::default()
     };
 
diff --git a/editor/src/mvc/update.rs b/editor/src/mvc/update.rs
index 8340985d66..4187cfe4db 100644
--- a/editor/src/mvc/update.rs
+++ b/editor/src/mvc/update.rs
@@ -2,6 +2,7 @@ use super::ed_model::{Position, RawSelection};
 use crate::text_buffer::TextBuffer;
 use crate::util::is_newline;
 use super::app_model::AppModel;
+use super::ed_model::EdModel;
 use crate::error::EdResult;
 use std::cmp::{max, min};
 
@@ -298,9 +299,15 @@ pub fn move_caret_down(
     (new_caret_pos, new_selection_opt)
 }
 
+fn del_selection(selection: RawSelection, ed_model: &mut EdModel)  -> EdResult<()> {
+    ed_model.text_buf.del_selection(selection)?;
+    ed_model.caret_pos = selection.start_pos;
+
+    Ok(())
+}
+
 pub fn handle_new_char(app_model: &mut AppModel, received_char: &char) -> EdResult<()> {
     if let Some(ref mut ed_model) = app_model.ed_model_opt {
-        ed_model.selection_opt = None;
         let old_caret_pos = ed_model.caret_pos;
 
         match received_char {
@@ -308,34 +315,46 @@ pub fn handle_new_char(app_model: &mut AppModel, received_char: &char) -> EdResu
                 // On Linux, '\u{8}' is backspace,
                 // on macOS '\u{7f}'.
                 if let Some(selection) = ed_model.selection_opt {
-                    ed_model.text_buf.del_selection(selection)?;
-                    ed_model.caret_pos = selection.start_pos;
+                    del_selection(selection, ed_model)?;
                 } else {
-                    ed_model.text_buf.pop_char(old_caret_pos);
-
                     ed_model.caret_pos =
                         move_caret_left(old_caret_pos, None, false, &ed_model.text_buf).0;
+
+                    ed_model.text_buf.pop_char(old_caret_pos);
                 }
             }
             ch if is_newline(ch) => {
-                ed_model.text_buf.insert_char(old_caret_pos, ch)?;
-                ed_model.caret_pos = Position {
-                    line: old_caret_pos.line + 1,
-                    column: 0,
-                };
+                if let Some(selection) = ed_model.selection_opt {
+                    del_selection(selection, ed_model)?;
+                    ed_model.text_buf.insert_char(ed_model.caret_pos, &'\n')?;
+                } else {
+                    ed_model.text_buf.insert_char(old_caret_pos, &'\n')?;
+
+                    ed_model.caret_pos = Position {
+                        line: old_caret_pos.line + 1,
+                        column: 0,
+                    };
+                }
             }
             '\u{e000}'..='\u{f8ff}' | '\u{f0000}'..='\u{ffffd}' | '\u{100000}'..='\u{10fffd}' => {
                 // These are private use characters; ignore them.
                 // See http://www.unicode.org/faq/private_use.html
             }
             _ => {
-                ed_model.text_buf.insert_char(old_caret_pos, received_char)?;
+                if let Some(selection) = ed_model.selection_opt {
+                    del_selection(selection, ed_model)?;
+                    ed_model.text_buf.insert_char(ed_model.caret_pos, received_char)?;
 
-                ed_model.caret_pos = Position {
-                    line: old_caret_pos.line,
-                    column: old_caret_pos.column + 1,
-                };
+                    ed_model.caret_pos =
+                        move_caret_right(ed_model.caret_pos, None, false, &ed_model.text_buf).0;
+                } else {
+                    ed_model.text_buf.insert_char(old_caret_pos, received_char)?;
 
+                    ed_model.caret_pos = Position {
+                        line: old_caret_pos.line,
+                        column: old_caret_pos.column + 1,
+                    };
+                }
             }
         }
 
@@ -344,3 +363,240 @@ pub fn handle_new_char(app_model: &mut AppModel, received_char: &char) -> EdResu
 
     Ok(())
 }
+
+
+#[cfg(test)]
+mod test_update {
+    use crate::selection::test_selection::{convert_dsl_to_selection, convert_selection_to_dsl, text_buffer_from_dsl_str, all_lines_vec};
+    use crate::mvc::ed_model::{Position, EdModel, RawSelection};
+    use crate::mvc::app_model::AppModel;
+    use crate::mvc::update::{handle_new_char};
+    use crate::text_buffer::TextBuffer;
+
+    fn gen_caret_text_buf(lines: &[&str]) -> Result<(Position, Option<RawSelection>, TextBuffer), String> {
+        let lines_string_slice: Vec<String> = lines.iter().map(|l| l.to_string()).collect();
+        let (selection_opt, caret_pos) = convert_dsl_to_selection(&lines_string_slice)?;
+        let text_buf = text_buffer_from_dsl_str(&lines_string_slice);
+
+        Ok((caret_pos, selection_opt, text_buf))
+    }
+
+    fn mock_app_model(text_buf: TextBuffer, caret_pos: Position, selection_opt: Option<RawSelection>) -> AppModel {
+        AppModel {
+            ed_model_opt: Some(
+                EdModel{
+                    text_buf,
+                    caret_pos,
+                    selection_opt,
+                    glyph_dim_rect_opt: None,
+                    has_focus: true
+                }
+            )
+        }
+    }
+
+    fn assert_insert(
+        pre_lines_str: &[&str],
+        expected_post_lines_str: &[&str],
+        new_char: char,
+    ) -> Result<(), String> {
+        let (caret_pos, selection_opt, pre_text_buf) = gen_caret_text_buf(pre_lines_str)?;
+        
+        let mut app_model = mock_app_model(pre_text_buf, caret_pos, selection_opt);
+
+        if let Err(e) = handle_new_char(&mut app_model, &new_char) {
+            return Err(e.to_string());
+        }
+
+        if let Some(ed_model) = app_model.ed_model_opt {
+            let mut actual_lines = all_lines_vec(&ed_model.text_buf);
+            let dsl_slice = convert_selection_to_dsl(ed_model.selection_opt, ed_model.caret_pos, &mut actual_lines).unwrap();
+            assert_eq!(dsl_slice, expected_post_lines_str);
+        } else {
+            panic!("Mock AppModel did not have an EdModel.");
+        }
+
+        Ok(())
+    }
+
+    #[test]
+    fn insert_new_char_simple() -> Result<(), String> {
+        assert_insert(
+            &["|"], &["a|"], 'a'
+        )?;
+        assert_insert(
+            &["|"], &[" |"], ' '
+        )?;
+        assert_insert(
+            &["a|"], &["aa|"], 'a'
+        )?;
+        assert_insert(
+            &["a|"], &["a |"], ' '
+        )?;
+        assert_insert(
+            &["a|\n", ""], &["ab|\n", ""], 'b'
+        )?;
+        assert_insert(
+            &["a|\n", ""], &["ab|\n", ""], 'b'
+        )?;
+        assert_insert(
+            &["a\n", "|"], &["a\n", "b|"], 'b'
+        )?;
+        assert_insert(
+            &["a\n", "b\n", "c|"], &["a\n", "b\n", "cd|"], 'd'
+        )?;
+        
+        Ok(())  
+    }
+
+    #[test]
+    fn insert_new_char_mid() -> Result<(), String> {
+        assert_insert(
+            &["ab|d"], &["abc|d"], 'c'
+        )?;
+        assert_insert(
+            &["a|cd"], &["ab|cd"], 'b'
+        )?;
+        assert_insert(
+            &["abc\n", "|e"], &["abc\n", "d|e"], 'd'
+        )?;
+        assert_insert(
+            &["abc\n", "def\n", "| "], &["abc\n", "def\n", "g| "], 'g'
+        )?;
+        assert_insert(
+            &["abc\n", "def\n", "| "], &["abc\n", "def\n", " | "], ' '
+        )?;
+
+        
+        Ok(())  
+    }
+
+    #[test]
+    fn simple_backspace() -> Result<(), String> {
+        assert_insert(
+            &["|"], &["|"], '\u{8}'
+        )?;
+        assert_insert(
+            &[" |"], &["|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a|"], &["|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["ab|"], &["a|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a|\n", ""], &["|\n", ""], '\u{8}'
+        )?;
+        assert_insert(
+            &["ab|\n", ""], &["a|\n", ""], '\u{8}'
+        )?;
+        assert_insert(
+            &["a\n", "|"], &["a|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a\n", "b\n", "c|"], &["a\n", "b\n", "|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a\n", "b\n", "|"], &["a\n", "b|"], '\u{8}'
+        )?;
+        
+        Ok(())  
+    }
+
+    #[test]
+    fn selection_backspace() -> Result<(), String> {
+        assert_insert(
+            &["[a]|"], &["|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a[a]|"], &["a|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["[aa]|"], &["|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a[b c]|"], &["a|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["[abc]|\n", ""], &["|\n", ""], '\u{8}'
+        )?;
+        assert_insert(
+            &["a\n", "[abc]|"], &["a\n","|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["[a\n", "abc]|"], &["|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a[b\n", "cdef ghij]|"], &["a|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["[a\n", "b\n", "c]|"], &["|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["a\n", "[b\n", "]|"], &["a\n", "|"], '\u{8}'
+        )?;
+        assert_insert(
+            &["abc\n", "d[ef\n", "ghi]|\n", "jkl"], &["abc\n", "d|\n", "jkl"], '\u{8}'
+        )?;
+        assert_insert(
+            &["abc\n", "[def\n", "ghi]|\n", "jkl"], &["abc\n", "|\n", "jkl"], '\u{8}'
+        )?;
+        assert_insert(
+            &["abc\n", "\n", "[def\n", "ghi]|\n", "jkl"], &["abc\n", "\n", "|\n", "jkl"], '\u{8}'
+        )?;
+        assert_insert(
+            &["[abc\n", "\n", "def\n", "ghi\n", "jkl]|"], &["|"], '\u{8}'
+        )?;
+
+        Ok(())  
+    }
+
+    #[test]
+    fn insert_with_selection() -> Result<(), String> {
+        assert_insert(
+            &["[a]|"], &["z|"], 'z'
+        )?;
+        assert_insert(
+            &["a[a]|"], &["az|"], 'z'
+        )?;
+        assert_insert(
+            &["[aa]|"], &["z|"], 'z'
+        )?;
+        assert_insert(
+            &["a[b c]|"], &["az|"], 'z'
+        )?;
+        assert_insert(
+            &["[abc]|\n", ""], &["z|\n", ""], 'z'
+        )?;
+        assert_insert(
+            &["a\n", "[abc]|"], &["a\n","z|"], 'z'
+        )?;
+        assert_insert(
+            &["[a\n", "abc]|"], &["z|"], 'z'
+        )?;
+        assert_insert(
+            &["a[b\n", "cdef ghij]|"], &["az|"], 'z'
+        )?;
+        assert_insert(
+            &["[a\n", "b\n", "c]|"], &["z|"], 'z'
+        )?;
+        assert_insert(
+            &["a\n", "[b\n", "]|"], &["a\n", "z|"], 'z'
+        )?;
+        assert_insert(
+            &["abc\n", "d[ef\n", "ghi]|\n", "jkl"], &["abc\n", "dz|\n", "jkl"], 'z'
+        )?;
+        assert_insert(
+            &["abc\n", "[def\n", "ghi]|\n", "jkl"], &["abc\n", "z|\n", "jkl"], 'z'
+        )?;
+        assert_insert(
+            &["abc\n", "\n", "[def\n", "ghi]|\n", "jkl"], &["abc\n", "\n", "z|\n", "jkl"], 'z'
+        )?;
+        assert_insert(
+            &["[abc\n", "\n", "def\n", "ghi\n", "jkl]|"], &["z|"], 'z'
+        )?;
+
+        Ok(())  
+    }
+}
diff --git a/editor/src/selection.rs b/editor/src/selection.rs
index 7d86dd1efd..1ff8f4c653 100644
--- a/editor/src/selection.rs
+++ b/editor/src/selection.rs
@@ -123,7 +123,7 @@ pub fn create_selection_rects<'a>(
 }
 
 #[cfg(test)]
-mod test_parse {
+pub mod test_selection {
     use crate::error::{EdResult, OutOfBounds};
     use crate::mvc::ed_model::{Position, RawSelection};
     use crate::mvc::update::{move_caret_down, move_caret_left, move_caret_right, move_caret_up, MoveCaretFun};
@@ -141,7 +141,7 @@ mod test_parse {
     pub struct LineParser;
 
     // show selection and caret position as symbols in lines for easy testing
-    fn convert_selection_to_dsl(
+    pub fn convert_selection_to_dsl(
         raw_sel_opt: Option<RawSelection>,
         caret_pos: Position,
         lines: &mut [String],
@@ -217,6 +217,16 @@ mod test_parse {
         }
     }
 
+    pub fn text_buffer_from_dsl_str(lines: &[String]) -> TextBuffer {
+        text_buffer_from_str(
+            &lines
+                .iter()
+                .map(|line| line.replace(&['[', ']', '|'][..], ""))
+                .collect::<Vec<String>>()
+                .join("")
+        )
+    }
+
     pub fn all_lines_vec(text_buf: &TextBuffer) -> Vec<String> {
         let mut lines: Vec<String> = Vec::new();
 
@@ -235,7 +245,7 @@ mod test_parse {
     }
 
     // Retrieve selection and position from formatted string
-    fn convert_dsl_to_selection(
+    pub fn convert_dsl_to_selection(
         lines: &[String],
     ) -> Result<(Option<RawSelection>, Position), String> {
         let lines_str: String = lines.join("");
@@ -349,13 +359,7 @@ mod test_parse {
         let (sel_opt, caret_pos) = convert_dsl_to_selection(&pre_lines)?;
 
         let clean_text_buf = 
-            text_buffer_from_str(
-                &pre_lines
-                    .into_iter()
-                    .map(|line| line.replace(&['[', ']', '|'][..], ""))
-                    .collect::<Vec<String>>()
-                    .join("")
-            );
+            text_buffer_from_dsl_str(&pre_lines);
 
         let (new_caret_pos, new_sel_opt) =
             move_fun(caret_pos, sel_opt, shift_pressed, &clean_text_buf);
diff --git a/editor/src/text_buffer.rs b/editor/src/text_buffer.rs
index 5bb34902e6..bc7c52cc14 100644
--- a/editor/src/text_buffer.rs
+++ b/editor/src/text_buffer.rs
@@ -23,7 +23,7 @@ impl TextBuffer {
     pub fn insert_char(&mut self, caret_pos: Position, new_char: &char)  -> EdResult<()> {
         let char_indx = self.pos_to_char_indx(caret_pos);
 
-        ensure!(char_indx > self.text_rope.len_chars(), OutOfBounds{
+        ensure!(char_indx <= self.text_rope.len_chars(), OutOfBounds{
             index: char_indx,
             collection_name: "Rope",
             len: self.text_rope.len_chars()
@@ -35,16 +35,17 @@ impl TextBuffer {
     }
 
     pub fn pop_char(&mut self, caret_pos: Position) {
-        let char_indx = self.pos_to_char_indx(caret_pos) - 1;
-        if char_indx < self.text_rope.len_chars() {
-            self.text_rope.remove(char_indx..char_indx);
+        let char_indx = self.pos_to_char_indx(caret_pos);
+
+        if (char_indx > 0) && char_indx <= self.text_rope.len_chars() {
+            self.text_rope.remove((char_indx - 1)..char_indx);
         }
     }
     
     pub fn del_selection(&mut self, raw_sel: RawSelection) -> EdResult<()> {
         let (start_char_indx, end_char_indx) = self.sel_to_tup(raw_sel)?;
 
-        ensure!(end_char_indx < self.text_rope.len_chars(), OutOfBounds{
+        ensure!(end_char_indx <= self.text_rope.len_chars(), OutOfBounds{
             index: end_char_indx,
             collection_name: "Rope",
             len: self.text_rope.len_chars()
@@ -102,7 +103,7 @@ impl TextBuffer {
     fn sel_to_tup(&self, raw_sel: RawSelection) -> EdResult<(usize, usize)> {
         let valid_sel = validate_selection(raw_sel)?;
         let start_char_indx = self.pos_to_char_indx(valid_sel.selection.start_pos);
-        let end_char_indx = self.pos_to_char_indx(valid_sel.selection.start_pos);
+        let end_char_indx = self.pos_to_char_indx(valid_sel.selection.end_pos);
 
         Ok((start_char_indx, end_char_indx))
     }