diff --git a/crates/maestro-tui/src/lib.rs b/crates/maestro-tui/src/lib.rs
index bc9ed0c..b76bd84 100644
--- a/crates/maestro-tui/src/lib.rs
+++ b/crates/maestro-tui/src/lib.rs
@@ -18,6 +18,7 @@ pub mod sidebar;
 pub mod state;
 pub mod tabs;
 pub mod terminal;
+pub mod text_input;
 
 use std::path::PathBuf;
 use std::time::Duration;
diff --git a/crates/maestro-tui/src/text_input.rs b/crates/maestro-tui/src/text_input.rs
new file mode 100644
index 0000000..402b7ce
--- /dev/null
+++ b/crates/maestro-tui/src/text_input.rs
@@ -0,0 +1,457 @@
+//! Single-line text-input primitive shared by every TUI form field.
+//!
+//! Owns a `String`, a character-indexed cursor, and horizontal scroll state.
+//! All editing goes through [`TextInput::handle_key`] so callers feed the same
+//! canonical [`InputKey`] stream the rest of the app uses; bracketed paste
+//! arrives as one [`InputKey::Paste`] and is inserted as a single operation.
+//!
+//! This is the one piece of the TUI form layer that unit-tests without a
+//! terminal: drive it with `InputKey` sequences and inspect value/cursor.
+
+use ratatui::buffer::Buffer;
+use ratatui::layout::Rect;
+use ratatui::style::Style;
+
+use crate::input::InputKey;
+
+#[derive(Debug, Default, Clone)]
+pub struct TextInput {
+    value: String,
+    /// Cursor position as a char offset into `value`.
+    cursor: usize,
+    /// Char offset of the leftmost visible cell.
+    scroll: usize,
+}
+
+impl TextInput {
+    pub fn with_value(value: impl Into<String>) -> Self {
+        let mut input = Self {
+            value: value.into(),
+            ..Self::default()
+        };
+        input.cursor = input.value.chars().count();
+        input
+    }
+
+    pub fn value(&self) -> &str {
+        &self.value
+    }
+
+    pub fn cursor(&self) -> usize {
+        self.cursor
+    }
+
+    /// Char offset of the leftmost visible cell; only meaningful after
+    /// [`TextInput::render`] has clamped it to the field width.
+    pub fn scroll_offset(&self) -> usize {
+        self.scroll
+    }
+
+    /// Insert `text` at the cursor as one operation. Used both for typed
+    /// characters and for whole bracketed-paste payloads.
+    pub fn insert(&mut self, text: &str) {
+        let at = self.byte_offset(self.cursor);
+        self.value.insert_str(at, text);
+        self.cursor += text.chars().count();
+    }
+
+    pub fn handle_key(&mut self, key: &InputKey) {
+        match key {
+            InputKey::Char {
+                c,
+                ctrl: false,
+                alt: false,
+                ..
+            } => self.insert(&c.to_string()),
+            InputKey::Char {
+                c: 'w', ctrl: true, ..
+            } => self.delete_word_backwards(),
+            InputKey::Char {
+                c: 'k', ctrl: true, ..
+            } => self.kill_to_end(),
+            // Emacs-style word motion; ctrl-arrow reaches us as a plain
+            // Left/Right today, so these are the dependable binding.
+            InputKey::Char {
+                c: 'b', ctrl: true, ..
+            } => self.cursor = self.word_left(),
+            InputKey::Char {
+                c: 'f', ctrl: true, ..
+            } => self.cursor = self.word_right(),
+            InputKey::Left => {
+                self.cursor = self.cursor.saturating_sub(1);
+            }
+            InputKey::Right => {
+                if self.cursor < self.value.chars().count() {
+                    self.cursor += 1;
+                }
+            }
+            InputKey::Home => self.cursor = 0,
+            InputKey::End => self.cursor = self.value.chars().count(),
+            InputKey::Backspace => {
+                if self.cursor > 0 {
+                    let at = self.byte_offset(self.cursor - 1);
+                    let end = self.byte_offset(self.cursor);
+                    self.value.replace_range(at..end, "");
+                    self.cursor -= 1;
+                }
+            }
+            InputKey::Delete => {
+                if self.cursor < self.value.chars().count() {
+                    let at = self.byte_offset(self.cursor);
+                    let end = self.byte_offset(self.cursor + 1);
+                    self.value.replace_range(at..end, "");
+                }
+            }
+            InputKey::Paste(text) => self.insert(text),
+            _ => {}
+        }
+    }
+
+    /// Draw into `area` (expected one row tall), scrolling horizontally so the
+    /// cursor stays visible, and return the screen column where the caller
+    /// should place the terminal cursor.
+    pub fn render(&mut self, area: Rect, buf: &mut Buffer, style: Style) -> u16 {
+        let width = area.width as usize;
+        let len = self.value.chars().count();
+        self.scroll = self.scroll.min(len);
+        if self.cursor < self.scroll {
+            self.scroll = self.cursor;
+        } else if width > 0 && self.cursor.saturating_sub(self.scroll) >= width {
+            self.scroll = self.cursor + 1 - width;
+        }
+        for (col, c) in self.value.chars().skip(self.scroll).take(width).enumerate() {
+            buf[(area.x + col as u16, area.y)]
+                .set_symbol(&c.to_string())
+                .set_style(style);
+        }
+        area.x + self.cursor.saturating_sub(self.scroll) as u16
+    }
+
+    fn byte_offset(&self, char_index: usize) -> usize {
+        self.value
+            .char_indices()
+            .nth(char_index)
+            .map(|(b, _)| b)
+            .unwrap_or(self.value.len())
+    }
+
+    fn is_word_char(c: char) -> bool {
+        c.is_alphanumeric() || c == '_'
+    }
+
+    /// Start of the word before the cursor, skipping any separators first —
+    /// emacs `backward-word`.
+    fn word_left(&self) -> usize {
+        let chars: Vec<char> = self.value.chars().collect();
+        let mut i = self.cursor;
+        while i > 0 && !Self::is_word_char(chars[i - 1]) {
+            i -= 1;
+        }
+        while i > 0 && Self::is_word_char(chars[i - 1]) {
+            i -= 1;
+        }
+        i
+    }
+
+    /// Start of the word after the cursor, skipping the rest of the current
+    /// word first — emacs `forward-word`.
+    fn word_right(&self) -> usize {
+        let chars: Vec<char> = self.value.chars().collect();
+        let len = chars.len();
+        let mut i = self.cursor;
+        while i < len && !Self::is_word_char(chars[i]) {
+            i += 1;
+        }
+        while i < len && Self::is_word_char(chars[i]) {
+            i += 1;
+        }
+        i
+    }
+
+    fn kill_to_end(&mut self) {
+        let at = self.byte_offset(self.cursor);
+        self.value.truncate(at);
+    }
+
+    /// Shell-style ctrl-w: kill back to the previous whitespace, taking any
+    /// trailing whitespace run with it — so `cd /tmp/foo` loses the whole
+    /// path segment in one keystroke.
+    fn delete_word_backwards(&mut self) {
+        let chars: Vec<char> = self.value.chars().collect();
+        let mut i = self.cursor;
+        while i > 0 && chars[i - 1].is_whitespace() {
+            i -= 1;
+        }
+        while i > 0 && !chars[i - 1].is_whitespace() {
+            i -= 1;
+        }
+        let at = self.byte_offset(i);
+        let end = self.byte_offset(self.cursor);
+        self.value.replace_range(at..end, "");
+        self.cursor = i;
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use InputKey::{Backspace, Delete, End, Home, Left, Right};
+
+    fn typed(s: &str) -> Vec<InputKey> {
+        s.chars().map(InputKey::char).collect()
+    }
+
+    fn fed(keys: &[InputKey]) -> TextInput {
+        let mut input = TextInput::default();
+        for k in keys {
+            input.handle_key(k);
+        }
+        input
+    }
+
+    fn ctrl(c: char) -> InputKey {
+        InputKey::ctrl_char(c)
+    }
+
+    #[test]
+    fn typing_lands_in_order() {
+        let input = fed(&typed("hello"));
+        assert_eq!(input.value(), "hello");
+        assert_eq!(input.cursor(), 5);
+    }
+
+    #[test]
+    fn backspace_removes_the_last_typed_char() {
+        let mut input = fed(&typed("hello"));
+        input.handle_key(&Backspace);
+        assert_eq!(input.value(), "hell");
+        assert_eq!(input.cursor(), 4);
+    }
+
+    #[test]
+    fn left_then_insert_fixes_a_middle_typo() {
+        let mut input = fed(&typed("helo"));
+        input.handle_key(&Left);
+        input.handle_key(&Left);
+        input.handle_key(&InputKey::char('l'));
+        assert_eq!(input.value(), "hello");
+        assert_eq!(input.cursor(), 3);
+    }
+
+    #[test]
+    fn motion_keys_stop_at_the_edges() {
+        let mut input = fed(&typed("abc"));
+        for _ in 0..5 {
+            input.handle_key(&Left);
+        }
+        assert_eq!(input.cursor(), 0);
+        input.handle_key(&Left);
+        assert_eq!(input.cursor(), 0);
+        for _ in 0..5 {
+            input.handle_key(&Right);
+        }
+        assert_eq!(input.cursor(), 3);
+    }
+
+    #[test]
+    fn home_and_end_jump_to_the_ends() {
+        let mut input = fed(&typed("abcdef"));
+        input.handle_key(&Home);
+        assert_eq!(input.cursor(), 0);
+        input.handle_key(&InputKey::char('x'));
+        assert_eq!(input.value(), "xabcdef");
+        input.handle_key(&End);
+        input.handle_key(&InputKey::char('!'));
+        assert_eq!(input.value(), "xabcdef!");
+    }
+
+    /// Cursor starts after the final `/`; word-left lands on word starts,
+    /// never inside a separator run.
+    #[test]
+    fn ctrl_b_walks_left_one_word_at_a_time() {
+        let mut input = TextInput::with_value("/tmp/foo bar-baz/");
+        assert_eq!(input.cursor(), 17);
+        for expected in [13, 9, 5, 1, 0, 0] {
+            input.handle_key(&ctrl('b'));
+            assert_eq!(input.cursor(), expected);
+        }
+    }
+
+    #[test]
+    fn ctrl_f_walks_right_one_word_at_a_time() {
+        let mut input = TextInput::with_value("/tmp/foo bar");
+        input.handle_key(&Home);
+        for expected in [4, 8, 12, 12] {
+            input.handle_key(&ctrl('f'));
+            assert_eq!(input.cursor(), expected);
+        }
+    }
+
+    #[test]
+    fn backspace_deletes_before_the_cursor() {
+        let mut input = fed(&typed("abcdef"));
+        input.handle_key(&Left);
+        input.handle_key(&Left);
+        input.handle_key(&Left);
+        input.handle_key(&Backspace);
+        assert_eq!(input.value(), "abdef");
+        assert_eq!(input.cursor(), 2);
+    }
+
+    #[test]
+    fn backspace_on_empty_input_is_a_noop() {
+        let mut input = TextInput::default();
+        input.handle_key(&Backspace);
+        assert_eq!(input.value(), "");
+        assert_eq!(input.cursor(), 0);
+    }
+
+    #[test]
+    fn delete_removes_the_char_under_the_cursor() {
+        let mut input = fed(&typed("abcdef"));
+        input.handle_key(&Home);
+        input.handle_key(&Delete);
+        assert_eq!(input.value(), "bcdef");
+        assert_eq!(input.cursor(), 0);
+    }
+
+    #[test]
+    fn delete_past_the_end_is_a_noop() {
+        let mut input = TextInput::with_value("abc");
+        input.handle_key(&End);
+        input.handle_key(&Delete);
+        assert_eq!(input.value(), "abc");
+    }
+
+    /// `cd /tmp/foo` with ctrl-w leaves `cd ` — the whole path segment is one
+    /// word to a shell (readline kills back to whitespace, spaces included).
+    #[test]
+    fn ctrl_w_deletes_the_word_behind_the_cursor() {
+        let mut input = fed(&[typed("cd ").as_slice(), typed("/tmp/foo").as_slice()].concat());
+        input.handle_key(&ctrl('w'));
+        assert_eq!(input.value(), "cd ");
+        assert_eq!(input.cursor(), 3);
+    }
+
+    #[test]
+    fn ctrl_w_stops_before_the_separator_run() {
+        let mut input = TextInput::with_value("a   b");
+        input.cursor = 5;
+        input.handle_key(&ctrl('w'));
+        assert_eq!(input.value(), "a   ");
+        assert_eq!(input.cursor(), 4);
+    }
+
+    #[test]
+    fn ctrl_k_kills_everything_after_the_cursor() {
+        let mut input = fed(&typed("spawn --debug extra"));
+        for _ in 0..14 {
+            input.handle_key(&Left);
+        }
+        input.handle_key(&ctrl('k'));
+        assert_eq!(input.value(), "spawn");
+        assert_eq!(input.cursor(), 5);
+    }
+
+    /// A paste arrives as one event carrying the whole payload and must land
+    /// at the cursor as a single insertion, not per-character.
+    #[test]
+    fn paste_inserts_whole_payload_at_the_cursor() {
+        let mut input = fed(&typed("cd "));
+        input.handle_key(&InputKey::Paste("/srv/work".into()));
+        assert_eq!(input.value(), "cd /srv/work");
+        assert_eq!(input.cursor(), 12);
+        // What follows still behaves like ordinary typed text.
+        input.handle_key(&InputKey::char('/'));
+        assert_eq!(input.value(), "cd /srv/work/");
+    }
+
+    #[test]
+    fn paste_between_existing_text_keeps_both_halves() {
+        let mut input = TextInput::with_value("ac");
+        input.handle_key(&Left);
+        input.handle_key(&InputKey::Paste("b×".into()));
+        assert_eq!(input.value(), "ab×c");
+        assert_eq!(input.cursor(), 3, "cursor counts chars, not bytes");
+    }
+
+    #[test]
+    fn rendering_an_empty_field_points_at_its_first_column() {
+        let mut input = TextInput::default();
+        let area = Rect::new(10, 5, 20, 1);
+        let mut buf = Buffer::empty(area);
+        let col = input.render(area, &mut buf, Style::default());
+        assert_eq!(col, 10);
+    }
+
+    #[test]
+    fn rendering_reports_the_visible_cursor_column() {
+        let mut input = TextInput::with_value("hello");
+        input.handle_key(&Left);
+        input.handle_key(&Left);
+        let area = Rect::new(10, 5, 20, 1);
+        let mut buf = Buffer::empty(area);
+        let col = input.render(area, &mut buf, Style::default());
+        assert_eq!(col, 13);
+        for (i, expected) in ["h", "e", "l", "l", "o"].iter().enumerate() {
+            assert_eq!(buf[(10 + i as u16, 5)].symbol(), *expected);
+        }
+    }
+
+    #[test]
+    fn rendering_a_value_wider_than_the_field_shows_its_tail() {
+        let value = "0123456789abcdefghij";
+        let mut input = TextInput::with_value(value);
+        let area = Rect::new(0, 0, 10, 1);
+        let mut buf = Buffer::empty(area);
+        let col = input.render(area, &mut buf, Style::default());
+        assert_eq!(col, 9, "cursor sits on the last visible column");
+        for (i, expected) in value.chars().skip(input.scroll_offset()).enumerate() {
+            assert_eq!(
+                buf[(i as u16, 0)].symbol(),
+                expected.to_string(),
+                "cell {i}"
+            );
+        }
+    }
+
+    /// Moving left into the hidden region must scroll the window back so the
+    /// cursor never disappears off the left edge.
+    #[test]
+    fn moving_left_into_the_hidden_region_scrolls_back() {
+        let value = "0123456789abcdefghij";
+        let mut input = TextInput::with_value(value);
+        let area = Rect::new(0, 0, 10, 1);
+        let mut buf = Buffer::empty(area);
+        input.render(area, &mut buf, Style::default());
+        assert_eq!(input.cursor(), 20);
+
+        input.handle_key(&Home);
+        for _ in 0..5 {
+            input.handle_key(&Right);
+        }
+        let mut buf = Buffer::empty(area);
+        let col = input.render(area, &mut buf, Style::default());
+        assert_eq!(input.cursor(), 5);
+        assert_eq!(
+            input.value().chars().nth(input.scroll),
+            Some('5'),
+            "window scrolled back to the cursor"
+        );
+        assert_eq!(col, 0);
+        assert_eq!(buf[(0, 0)].symbol(), "5");
+    }
+
+    #[test]
+    fn shrinking_the_value_clamps_scroll_and_cursor() {
+        let mut input = TextInput::with_value("0123456789abcdefghij");
+        input.handle_key(&Home);
+        input.handle_key(&ctrl('k'));
+        let area = Rect::new(0, 0, 10, 1);
+        let mut buf = Buffer::empty(area);
+        let col = input.render(area, &mut buf, Style::default());
+        assert_eq!(input.value(), "");
+        assert_eq!(col, 0);
+    }
+}