diff --git a/crates/maestro-tui/src/lib.rs b/crates/maestro-tui/src/lib.rs
index d180427..80745b7 100644
--- a/crates/maestro-tui/src/lib.rs
+++ b/crates/maestro-tui/src/lib.rs
@@ -13,6 +13,7 @@ pub mod emulators;
 pub mod fast_forward;
 pub mod input;
 pub mod keymap;
+pub mod matcher;
 pub mod overlays;
 pub mod palette;
 pub mod pane;
diff --git a/crates/maestro-tui/src/matcher.rs b/crates/maestro-tui/src/matcher.rs
new file mode 100644
index 0000000..e552b17
--- /dev/null
+++ b/crates/maestro-tui/src/matcher.rs
@@ -0,0 +1,750 @@
+//! Pure match-and-rank function for the `ctrl-k` command bar.
+//!
+//! Implements exactly the algorithm in `docs/COMMAND-BAR.md` ("What a
+//! candidate is", "Match and rank", "Fixtures"). Must produce the same order
+//! and scores as `web/src/matcher.ts` for the same input.
+
+use std::collections::HashMap;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum CandidateKind {
+    Session,
+    Command,
+    Directory,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum MatchFieldName {
+    Name,
+    Directory,
+    Command,
+    Tool,
+    Label,
+    Path,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct SessionCandidate {
+    pub name: String,
+    pub directory: Option<String>,
+    pub command: Option<String>,
+    pub tool: Option<String>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct CommandCandidate {
+    pub label: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct DirectoryCandidate {
+    pub path: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum MatchCandidate {
+    Session(SessionCandidate),
+    Command(CommandCandidate),
+    Directory(DirectoryCandidate),
+}
+
+pub type MatchRange = (usize, usize);
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct MatchResult<'c> {
+    pub candidate: &'c MatchCandidate,
+    pub score: i32,
+    pub field: Option<MatchFieldName>,
+    pub ranges: Vec<MatchRange>,
+}
+
+struct Field<'c> {
+    name: MatchFieldName,
+    text: &'c str,
+    weight: i32,
+}
+
+impl MatchCandidate {
+    fn kind(&self) -> CandidateKind {
+        match self {
+            MatchCandidate::Session(_) => CandidateKind::Session,
+            MatchCandidate::Command(_) => CandidateKind::Command,
+            MatchCandidate::Directory(_) => CandidateKind::Directory,
+        }
+    }
+
+    fn fields(&self) -> Vec<Field<'_>> {
+        match self {
+            MatchCandidate::Session(session) => {
+                let mut fields = vec![Field {
+                    name: MatchFieldName::Name,
+                    text: &session.name,
+                    weight: 0,
+                }];
+                if let Some(directory) = &session.directory {
+                    fields.push(Field {
+                        name: MatchFieldName::Directory,
+                        text: directory,
+                        weight: -24,
+                    });
+                }
+                if let Some(command) = &session.command {
+                    fields.push(Field {
+                        name: MatchFieldName::Command,
+                        text: command,
+                        weight: -32,
+                    });
+                }
+                if let Some(tool) = &session.tool {
+                    fields.push(Field {
+                        name: MatchFieldName::Tool,
+                        text: tool,
+                        weight: -40,
+                    });
+                }
+                fields
+            }
+            MatchCandidate::Command(command) => vec![Field {
+                name: MatchFieldName::Label,
+                text: &command.label,
+                weight: 0,
+            }],
+            MatchCandidate::Directory(directory) => vec![Field {
+                name: MatchFieldName::Path,
+                text: &directory.path,
+                weight: 0,
+            }],
+        }
+    }
+}
+
+fn kind_order(kind: CandidateKind) -> u8 {
+    match kind {
+        CandidateKind::Session => 0,
+        CandidateKind::Command => 1,
+        CandidateKind::Directory => 2,
+    }
+}
+
+fn lower_char(c: char) -> char {
+    c.to_lowercase().next().unwrap_or(c)
+}
+
+fn lower_chars(chars: &[char]) -> Vec<char> {
+    chars.iter().copied().map(lower_char).collect()
+}
+
+fn normalize_query(query: &str) -> Vec<char> {
+    query
+        .chars()
+        .filter(|c| !c.is_whitespace())
+        .map(lower_char)
+        .collect()
+}
+
+const SEPARATORS: [char; 6] = ['/', '\\', '-', '_', '.', ':'];
+
+fn boundary_bonus(text: &[char], position: usize) -> i32 {
+    if position == 0 {
+        return 18;
+    }
+
+    let previous = text[position - 1];
+    if previous == ' ' || SEPARATORS.contains(&previous) {
+        return 16;
+    }
+
+    let current = text[position];
+    if current.is_uppercase() && previous.is_lowercase() {
+        return 12;
+    }
+
+    let is_digit = current.is_ascii_digit();
+    let previous_is_digit = previous.is_ascii_digit();
+    if is_digit && !previous_is_digit {
+        return 12;
+    }
+
+    0
+}
+
+fn contribution(text: &[char], position: usize, previous_position: isize) -> i32 {
+    let gap = position as isize - previous_position - 1;
+    16 + boundary_bonus(text, position) + if gap == 0 { 8 } else { -gap.min(12) as i32 }
+}
+
+#[derive(Clone)]
+struct Embedding {
+    score: i32,
+    positions: Vec<usize>,
+}
+
+fn is_better_embedding(candidate: &Embedding, incumbent: Option<&Embedding>) -> bool {
+    let Some(incumbent) = incumbent else {
+        return true;
+    };
+    if candidate.score != incumbent.score {
+        return candidate.score > incumbent.score;
+    }
+    for (c, i) in candidate.positions.iter().zip(incumbent.positions.iter()) {
+        if c != i {
+            return c < i;
+        }
+    }
+    false
+}
+
+/// The dynamic program over `(query index, text position)` described in
+/// "Which embedding": greedy leftmost-first matching is insufficient (e.g.
+/// `mtu` against `maestro-tui`), so every reachable position at each query
+/// index carries its best score and position vector forward.
+fn best_embedding(query: &[char], text: &[char]) -> Option<Embedding> {
+    let lower_text = lower_chars(text);
+    let mut previous_states: HashMap<usize, Embedding> = HashMap::new();
+
+    for (query_index, &qc) in query.iter().enumerate() {
+        let mut states: HashMap<usize, Embedding> = HashMap::new();
+
+        for (position, &text_char) in lower_text.iter().enumerate() {
+            if text_char != qc {
+                continue;
+            }
+
+            if query_index == 0 {
+                states.insert(
+                    position,
+                    Embedding {
+                        score: contribution(text, position, -1),
+                        positions: vec![position],
+                    },
+                );
+                continue;
+            }
+
+            for (&previous_position, previous) in previous_states.iter() {
+                if previous_position >= position {
+                    continue;
+                }
+                let mut positions = previous.positions.clone();
+                positions.push(position);
+                let candidate = Embedding {
+                    score: previous.score
+                        + contribution(text, position, previous_position as isize),
+                    positions,
+                };
+                if is_better_embedding(&candidate, states.get(&position)) {
+                    states.insert(position, candidate);
+                }
+            }
+        }
+
+        if states.is_empty() {
+            return None;
+        }
+        previous_states = states;
+    }
+
+    let mut best: Option<Embedding> = None;
+    for embedding in previous_states.into_values() {
+        if is_better_embedding(&embedding, best.as_ref()) {
+            best = Some(embedding);
+        }
+    }
+    best
+}
+
+fn to_ranges(positions: &[usize]) -> Vec<MatchRange> {
+    let mut ranges: Vec<MatchRange> = Vec::new();
+    for &position in positions {
+        if let Some(last) = ranges.last_mut() {
+            if last.1 == position {
+                last.1 = position + 1;
+                continue;
+            }
+        }
+        ranges.push((position, position + 1));
+    }
+    ranges
+}
+
+fn compact(text: &str) -> String {
+    text.chars()
+        .filter(|c| !c.is_whitespace())
+        .map(lower_char)
+        .collect()
+}
+
+struct Ranked<'c> {
+    candidate: &'c MatchCandidate,
+    score: i32,
+    field: Option<MatchFieldName>,
+    ranges: Vec<MatchRange>,
+    matched_text: String,
+    input_index: usize,
+}
+
+/// `(query, candidates) -> ranked subset with matched ranges`. Knows nothing
+/// about sessions, panes or the network — see docs/COMMAND-BAR.md.
+pub fn match_and_rank<'c>(query: &str, candidates: &'c [MatchCandidate]) -> Vec<MatchResult<'c>> {
+    let normalized_query = normalize_query(query);
+
+    if normalized_query.is_empty() {
+        return candidates
+            .iter()
+            .map(|candidate| MatchResult {
+                candidate,
+                score: 0,
+                field: None,
+                ranges: Vec::new(),
+            })
+            .collect();
+    }
+
+    let mut results: Vec<Ranked<'c>> = Vec::new();
+
+    for (input_index, candidate) in candidates.iter().enumerate() {
+        let mut best: Option<(MatchFieldName, &str, i32, Vec<usize>)> = None;
+
+        for field in candidate.fields() {
+            let text_chars: Vec<char> = field.text.chars().collect();
+            let Some(embedding) = best_embedding(&normalized_query, &text_chars) else {
+                continue;
+            };
+
+            let compact_text = compact(field.text);
+            let normalized_query_str: String = normalized_query.iter().collect();
+            let adjustment = if compact_text == normalized_query_str {
+                64
+            } else if compact_text.starts_with(&normalized_query_str) {
+                32
+            } else {
+                0
+            };
+            let score = embedding.score + adjustment + field.weight;
+
+            let is_better = match &best {
+                None => true,
+                Some((_, _, best_score, _)) => score > *best_score,
+            };
+            if is_better {
+                best = Some((field.name, field.text, score, embedding.positions));
+            }
+        }
+
+        if let Some((field_name, field_text, score, positions)) = best {
+            results.push(Ranked {
+                candidate,
+                score,
+                field: Some(field_name),
+                ranges: to_ranges(&positions),
+                matched_text: field_text.to_string(),
+                input_index,
+            });
+        }
+    }
+
+    results.sort_by(|a, b| {
+        b.score
+            .cmp(&a.score)
+            .then_with(|| kind_order(a.candidate.kind()).cmp(&kind_order(b.candidate.kind())))
+            .then_with(|| {
+                a.matched_text
+                    .chars()
+                    .count()
+                    .cmp(&b.matched_text.chars().count())
+            })
+            .then_with(|| a.matched_text.cmp(&b.matched_text))
+            .then_with(|| a.input_index.cmp(&b.input_index))
+    });
+
+    results
+        .into_iter()
+        .map(|ranked| MatchResult {
+            candidate: ranked.candidate,
+            score: ranked.score,
+            field: ranked.field,
+            ranges: ranked.ranges,
+        })
+        .collect()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn session(
+        name: &str,
+        directory: Option<&str>,
+        command: Option<&str>,
+        tool: Option<&str>,
+    ) -> MatchCandidate {
+        MatchCandidate::Session(SessionCandidate {
+            name: name.to_string(),
+            directory: directory.map(str::to_string),
+            command: command.map(str::to_string),
+            tool: tool.map(str::to_string),
+        })
+    }
+
+    fn command(label: &str) -> MatchCandidate {
+        MatchCandidate::Command(CommandCandidate {
+            label: label.to_string(),
+        })
+    }
+
+    fn directory(path: &str) -> MatchCandidate {
+        MatchCandidate::Directory(DirectoryCandidate {
+            path: path.to_string(),
+        })
+    }
+
+    fn label(candidate: &MatchCandidate) -> String {
+        match candidate {
+            MatchCandidate::Session(s) => format!("session:{}", s.name),
+            MatchCandidate::Command(c) => format!("command:{}", c.label),
+            MatchCandidate::Directory(d) => format!("directory:{}", d.path),
+        }
+    }
+
+    fn positions(result: &MatchResult) -> Vec<usize> {
+        result
+            .ranges
+            .iter()
+            .flat_map(|&(start, end)| start..end)
+            .collect()
+    }
+
+    #[allow(clippy::type_complexity)]
+    fn expect_results(
+        query: &str,
+        candidates: &[MatchCandidate],
+        expected: &[(&str, i32, Option<MatchFieldName>, &[usize])],
+    ) {
+        let results = match_and_rank(query, candidates);
+
+        let actual: Vec<(String, i32)> = results
+            .iter()
+            .map(|r| (label(r.candidate), r.score))
+            .collect();
+        let expected_labels: Vec<(String, i32)> = expected
+            .iter()
+            .map(|(l, s, _, _)| (l.to_string(), *s))
+            .collect();
+        assert_eq!(actual, expected_labels, "order/scores for query {query:?}");
+
+        let actual_fields: Vec<Option<MatchFieldName>> = results.iter().map(|r| r.field).collect();
+        let expected_fields: Vec<Option<MatchFieldName>> =
+            expected.iter().map(|(_, _, f, _)| *f).collect();
+        assert_eq!(actual_fields, expected_fields, "fields for query {query:?}");
+
+        let actual_positions: Vec<Vec<usize>> = results.iter().map(positions).collect();
+        let expected_positions: Vec<Vec<usize>> =
+            expected.iter().map(|(_, _, _, p)| p.to_vec()).collect();
+        assert_eq!(
+            actual_positions, expected_positions,
+            "positions for query {query:?}"
+        );
+    }
+
+    #[test]
+    fn f1_empty_query_keeps_input_order() {
+        expect_results(
+            "",
+            &[
+                session("kill", Some("~/dev/api"), Some("bash"), None),
+                session(
+                    "killer-app",
+                    Some("~/dev/killer-app"),
+                    Some("claude --resume"),
+                    Some("claude"),
+                ),
+                command("Kill selected session"),
+            ],
+            &[
+                ("session:kill", 0, None, &[]),
+                ("session:killer-app", 0, None, &[]),
+                ("command:Kill selected session", 0, None, &[]),
+            ],
+        );
+    }
+
+    #[test]
+    fn f2_exact_session_name_beats_prefix_kind_breaks_tie() {
+        expect_results(
+            "kill",
+            &[
+                session("kill", Some("~/dev/api"), Some("bash"), None),
+                session(
+                    "killer-app",
+                    Some("~/dev/killer-app"),
+                    Some("claude --resume"),
+                    Some("claude"),
+                ),
+                command("Kill selected session"),
+            ],
+            &[
+                (
+                    "session:kill",
+                    178,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2, 3],
+                ),
+                (
+                    "session:killer-app",
+                    146,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2, 3],
+                ),
+                (
+                    "command:Kill selected session",
+                    146,
+                    Some(MatchFieldName::Label),
+                    &[0, 1, 2, 3],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f3_path_segment_boundaries_beat_mid_segment() {
+        expect_results(
+            "foo",
+            &[
+                directory("~/dev/foobar"),
+                directory("~/src/myfoo"),
+                directory("~/foo"),
+            ],
+            &[
+                (
+                    "directory:~/foo",
+                    78,
+                    Some(MatchFieldName::Path),
+                    &[2, 3, 4],
+                ),
+                (
+                    "directory:~/dev/foobar",
+                    74,
+                    Some(MatchFieldName::Path),
+                    &[6, 7, 8],
+                ),
+                (
+                    "directory:~/src/myfoo",
+                    56,
+                    Some(MatchFieldName::Path),
+                    &[8, 9, 10],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f4_no_match_returns_empty() {
+        expect_results(
+            "zzz",
+            &[
+                session("kill", Some("~/dev/api"), Some("bash"), None),
+                command("Kill selected session"),
+            ],
+            &[],
+        );
+    }
+
+    #[test]
+    fn f5_highest_scoring_embedding_beats_greedy() {
+        expect_results(
+            "mtu",
+            &[
+                session("maestro-tui", None, None, None),
+                session("maestro-daemon", None, None, None),
+                session("mtui-scratch", None, None, None),
+            ],
+            &[
+                (
+                    "session:mtui-scratch",
+                    122,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2],
+                ),
+                (
+                    "session:maestro-tui",
+                    91,
+                    Some(MatchFieldName::Name),
+                    &[0, 8, 9],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f6_name_beats_weighted_directory() {
+        expect_results(
+            "api",
+            &[
+                session("api", Some("~/dev/web"), Some("bash"), None),
+                session("worker", Some("~/dev/api"), Some("bash"), None),
+            ],
+            &[
+                ("session:api", 154, Some(MatchFieldName::Name), &[0, 1, 2]),
+                (
+                    "session:worker",
+                    50,
+                    Some(MatchFieldName::Directory),
+                    &[6, 7, 8],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f7_case_insensitive_length_breaks_tie() {
+        expect_results(
+            "api",
+            &[
+                session("API-Gateway", None, None, None),
+                session("apiary", None, None, None),
+            ],
+            &[
+                (
+                    "session:apiary",
+                    122,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2],
+                ),
+                (
+                    "session:API-Gateway",
+                    122,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f8_exact_tool_beats_command_field() {
+        expect_results(
+            "claude",
+            &[
+                session(
+                    "nameless",
+                    Some("~/dev/x"),
+                    Some("claude --resume"),
+                    Some("claude"),
+                ),
+                session("clay", Some("~/dev/y"), Some("bash"), None),
+            ],
+            &[(
+                "session:nameless",
+                186,
+                Some(MatchFieldName::Tool),
+                &[0, 1, 2, 3, 4, 5],
+            )],
+        );
+    }
+
+    #[test]
+    fn f9_separator_earns_word_boundary_bonus() {
+        expect_results(
+            "ws",
+            &[
+                session("websearch", None, None, None),
+                session("web-search", None, None, None),
+            ],
+            &[
+                (
+                    "session:web-search",
+                    71,
+                    Some(MatchFieldName::Name),
+                    &[0, 4],
+                ),
+                ("session:websearch", 56, Some(MatchFieldName::Name), &[0, 3]),
+            ],
+        );
+    }
+
+    #[test]
+    fn f10_command_labels_rank_by_boundary_and_gap() {
+        expect_results(
+            "se",
+            &[
+                command("Kill selected session"),
+                command("Create a session"),
+                command("Show help"),
+            ],
+            &[
+                (
+                    "command:Show help",
+                    53,
+                    Some(MatchFieldName::Label),
+                    &[0, 6],
+                ),
+                (
+                    "command:Kill selected session",
+                    51,
+                    Some(MatchFieldName::Label),
+                    &[5, 6],
+                ),
+                (
+                    "command:Create a session",
+                    47,
+                    Some(MatchFieldName::Label),
+                    &[9, 10],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f11_directory_matches_separate_on_initial_gap() {
+        expect_results(
+            "dev",
+            &[
+                session("api", Some("~/dev/api"), Some("bash"), None),
+                session("notes", Some("~/documents/dev-notes"), Some("nvim"), None),
+                session("scratch", Some("~/srv/devops"), Some("bash"), None),
+            ],
+            &[
+                (
+                    "session:api",
+                    54,
+                    Some(MatchFieldName::Directory),
+                    &[2, 3, 4],
+                ),
+                (
+                    "session:scratch",
+                    50,
+                    Some(MatchFieldName::Directory),
+                    &[6, 7, 8],
+                ),
+                (
+                    "session:notes",
+                    44,
+                    Some(MatchFieldName::Directory),
+                    &[12, 13, 14],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f12_exact_beats_prefix() {
+        expect_results(
+            "quit",
+            &[command("Quit Maestro"), command("Quit")],
+            &[
+                (
+                    "command:Quit",
+                    178,
+                    Some(MatchFieldName::Label),
+                    &[0, 1, 2, 3],
+                ),
+                (
+                    "command:Quit Maestro",
+                    146,
+                    Some(MatchFieldName::Label),
+                    &[0, 1, 2, 3],
+                ),
+            ],
+        );
+    }
+}