diff --git a/rustitch/src/dst/mod.rs b/rustitch/src/dst/mod.rs
new file mode 100644
index 0000000..a73ec6c
--- /dev/null
+++ b/rustitch/src/dst/mod.rs
@@ -0,0 +1,180 @@
+use crate::error::Error;
+use crate::palette::default_colors;
+use crate::types::{ResolvedDesign, StitchCommand};
+
+/// Parse a DST (Tajima) file from raw bytes into stitch commands.
+///
+/// DST format: 3 bytes per stitch record with bit-packed dx, dy, and control flags.
+/// The standard Tajima bit layout maps specific bits across all 3 bytes to coordinate values.
+pub fn parse(data: &[u8]) -> Result<Vec<StitchCommand>, Error> {
+    if data.len() < 3 {
+        return Err(Error::TooShort {
+            expected: 3,
+            actual: data.len(),
+        });
+    }
+
+    // DST files may have a 512-byte header; stitch data can start at byte 512
+    // if the file is large enough, or at byte 0 for raw stitch streams.
+    // The header contains "LA:" at offset 0 if present.
+    let offset = if data.len() > 512 && &data[0..3] == b"LA:" {
+        512
+    } else {
+        0
+    };
+
+    let stitch_data = &data[offset..];
+    if stitch_data.len() < 3 {
+        return Err(Error::NoStitchData);
+    }
+
+    let mut commands = Vec::new();
+    let mut i = 0;
+
+    while i + 2 < stitch_data.len() {
+        let b0 = stitch_data[i];
+        let b1 = stitch_data[i + 1];
+        let b2 = stitch_data[i + 2];
+        i += 3;
+
+        // End of file: byte 2 bits 0 and 1 both set, and specific pattern
+        if b2 & 0x03 == 0x03 {
+            commands.push(StitchCommand::End);
+            break;
+        }
+
+        let dx = decode_dx(b0, b1, b2);
+        let dy = decode_dy(b0, b1, b2);
+
+        // Color change: byte 2 bit 7
+        if b2 & 0x80 != 0 {
+            commands.push(StitchCommand::ColorChange);
+            continue;
+        }
+
+        // Jump: byte 2 bit 6
+        if b2 & 0x40 != 0 {
+            commands.push(StitchCommand::Jump { dx, dy });
+            continue;
+        }
+
+        commands.push(StitchCommand::Stitch { dx, dy });
+    }
+
+    if commands.is_empty() || (commands.len() == 1 && matches!(commands[0], StitchCommand::End)) {
+        return Err(Error::NoStitchData);
+    }
+
+    // Ensure we have an End marker
+    if !matches!(commands.last(), Some(StitchCommand::End)) {
+        commands.push(StitchCommand::End);
+    }
+
+    Ok(commands)
+}
+
+/// Decode X displacement from the 3-byte Tajima record.
+/// Standard bit layout for dx across bytes b0, b1, b2.
+fn decode_dx(b0: u8, b1: u8, b2: u8) -> i16 {
+    let mut x: i16 = 0;
+    if b0 & 0x01 != 0 { x += 1; }
+    if b0 & 0x02 != 0 { x -= 1; }
+    if b0 & 0x04 != 0 { x += 9; }
+    if b0 & 0x08 != 0 { x -= 9; }
+    if b1 & 0x01 != 0 { x += 3; }
+    if b1 & 0x02 != 0 { x -= 3; }
+    if b1 & 0x04 != 0 { x += 27; }
+    if b1 & 0x08 != 0 { x -= 27; }
+    if b2 & 0x04 != 0 { x += 81; }
+    if b2 & 0x08 != 0 { x -= 81; }
+    x
+}
+
+/// Decode Y displacement from the 3-byte Tajima record.
+/// Standard bit layout for dy across bytes b0, b1, b2.
+fn decode_dy(b0: u8, b1: u8, b2: u8) -> i16 {
+    let mut y: i16 = 0;
+    if b0 & 0x80 != 0 { y += 1; }
+    if b0 & 0x40 != 0 { y -= 1; }
+    if b0 & 0x20 != 0 { y += 9; }
+    if b0 & 0x10 != 0 { y -= 9; }
+    if b1 & 0x80 != 0 { y += 3; }
+    if b1 & 0x40 != 0 { y -= 3; }
+    if b1 & 0x20 != 0 { y += 27; }
+    if b1 & 0x10 != 0 { y -= 27; }
+    if b2 & 0x20 != 0 { y += 81; }
+    if b2 & 0x10 != 0 { y -= 81; }
+    // DST Y axis is inverted (positive = up in machine coords, down in screen coords)
+    -y
+}
+
+/// Parse a DST file and resolve to a renderable design.
+pub fn parse_and_resolve(data: &[u8]) -> Result<ResolvedDesign, Error> {
+    let commands = parse(data)?;
+    let color_count = commands
+        .iter()
+        .filter(|c| matches!(c, StitchCommand::ColorChange))
+        .count()
+        + 1;
+    let colors = default_colors(color_count);
+    crate::resolve::resolve(&commands, colors)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn decode_end_marker() {
+        // b2 = 0x03 means end
+        let data = [0x00, 0x00, 0x03];
+        let cmds = parse(&data).unwrap_err();
+        assert!(matches!(cmds, Error::NoStitchData));
+    }
+
+    #[test]
+    fn decode_simple_stitch() {
+        // A normal stitch followed by end
+        // dx=+1: b0 bit 0. dy=+1: b0 bit 7. b2=0x00 (normal stitch)
+        // Then end marker
+        let data = [0x81, 0x00, 0x00, 0x00, 0x00, 0x03];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(cmds[0], StitchCommand::Stitch { dx: 1, dy: -1 }));
+        assert!(matches!(cmds[1], StitchCommand::End));
+    }
+
+    #[test]
+    fn decode_jump() {
+        // b2 bit 6 = jump
+        let data = [0x01, 0x00, 0x40, 0x00, 0x00, 0x03];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(cmds[0], StitchCommand::Jump { dx: 1, dy: 0 }));
+    }
+
+    #[test]
+    fn decode_color_change() {
+        // b2 bit 7 = color change
+        let data = [0x00, 0x00, 0x80, 0x01, 0x00, 0x00, 0x00, 0x00, 0x03];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(cmds[0], StitchCommand::ColorChange));
+    }
+
+    #[test]
+    fn decode_dx_values() {
+        assert_eq!(decode_dx(0x01, 0x00, 0x00), 1);
+        assert_eq!(decode_dx(0x02, 0x00, 0x00), -1);
+        assert_eq!(decode_dx(0x04, 0x00, 0x00), 9);
+        assert_eq!(decode_dx(0x00, 0x04, 0x00), 27);
+        assert_eq!(decode_dx(0x00, 0x00, 0x04), 81);
+        assert_eq!(decode_dx(0x05, 0x05, 0x04), 1 + 9 + 27 + 81); // 118
+    }
+
+    #[test]
+    fn decode_dy_values() {
+        assert_eq!(decode_dy(0x80, 0x00, 0x00), -1);
+        assert_eq!(decode_dy(0x40, 0x00, 0x00), 1);
+        assert_eq!(decode_dy(0x20, 0x00, 0x00), -9);
+        assert_eq!(decode_dy(0x00, 0x20, 0x00), -27);
+        assert_eq!(decode_dy(0x00, 0x00, 0x20), -81);
+    }
+}
diff --git a/rustitch/src/error.rs b/rustitch/src/error.rs
new file mode 100644
index 0000000..f325741
--- /dev/null
+++ b/rustitch/src/error.rs
@@ -0,0 +1,23 @@
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error("invalid PES magic: expected #PES, got {0:?}")]
+    InvalidPesMagic([u8; 4]),
+    #[error("file too short: need {expected} bytes, got {actual}")]
+    TooShort { expected: usize, actual: usize },
+    #[error("invalid PEC offset: {0} exceeds file length {1}")]
+    InvalidPecOffset(u32, usize),
+    #[error("invalid header: {0}")]
+    InvalidHeader(String),
+    #[error("no stitch data found")]
+    NoStitchData,
+    #[error("empty design: no stitch segments produced")]
+    EmptyDesign,
+    #[error("unsupported format")]
+    UnsupportedFormat,
+    #[error("render error: {0}")]
+    Render(String),
+    #[error("PNG encoding error: {0}")]
+    PngEncode(#[from] png::EncodingError),
+}
diff --git a/rustitch/src/exp.rs b/rustitch/src/exp.rs
new file mode 100644
index 0000000..6ff0b58
--- /dev/null
+++ b/rustitch/src/exp.rs
@@ -0,0 +1,135 @@
+use crate::error::Error;
+use crate::palette::default_colors;
+use crate::types::{ResolvedDesign, StitchCommand};
+
+/// Parse an EXP (Melco) file from raw bytes into stitch commands.
+///
+/// EXP format: 2 bytes per stitch (signed i8 dx, dy).
+/// Escape byte 0x80 followed by a control byte:
+///   0x01 = color change
+///   0x02 = color change (variant)
+///   0x04 = jump (next 2 bytes are jump dx, dy)
+///   0x80 = trim
+pub fn parse(data: &[u8]) -> Result<Vec<StitchCommand>, Error> {
+    if data.len() < 2 {
+        return Err(Error::TooShort {
+            expected: 2,
+            actual: data.len(),
+        });
+    }
+
+    let mut commands = Vec::new();
+    let mut i = 0;
+
+    while i + 1 < data.len() {
+        let b1 = data[i];
+        let b2 = data[i + 1];
+
+        if b1 == 0x80 {
+            match b2 {
+                0x01 | 0x02 => {
+                    commands.push(StitchCommand::ColorChange);
+                    i += 2;
+                }
+                0x80 => {
+                    commands.push(StitchCommand::Trim);
+                    i += 2;
+                }
+                0x04 => {
+                    // Jump: next 2 bytes are the movement
+                    i += 2;
+                    if i + 1 >= data.len() {
+                        break;
+                    }
+                    let dx = data[i] as i8 as i16;
+                    let dy = data[i + 1] as i8 as i16;
+                    commands.push(StitchCommand::Jump { dx, dy });
+                    i += 2;
+                }
+                _ => {
+                    // Unknown escape, skip
+                    i += 2;
+                }
+            }
+        } else {
+            let dx = b1 as i8 as i16;
+            let dy = b2 as i8 as i16;
+            commands.push(StitchCommand::Stitch { dx, dy });
+            i += 2;
+        }
+    }
+
+    commands.push(StitchCommand::End);
+
+    if commands.len() <= 1 {
+        return Err(Error::NoStitchData);
+    }
+
+    Ok(commands)
+}
+
+/// Parse an EXP file and resolve to a renderable design.
+pub fn parse_and_resolve(data: &[u8]) -> Result<ResolvedDesign, Error> {
+    let commands = parse(data)?;
+    let color_count = commands
+        .iter()
+        .filter(|c| matches!(c, StitchCommand::ColorChange))
+        .count()
+        + 1;
+    let colors = default_colors(color_count);
+    crate::resolve::resolve(&commands, colors)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parse_simple_stitches() {
+        let data = [0x0A, 0x14, 0x05, 0x03];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(
+            cmds[0],
+            StitchCommand::Stitch { dx: 10, dy: 20 }
+        ));
+        assert!(matches!(cmds[1], StitchCommand::Stitch { dx: 5, dy: 3 }));
+        assert!(matches!(cmds[2], StitchCommand::End));
+    }
+
+    #[test]
+    fn parse_negative_coords() {
+        // -10 as i8 = 0xF6, -20 as i8 = 0xEC
+        let data = [0xF6, 0xEC];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(
+            cmds[0],
+            StitchCommand::Stitch { dx: -10, dy: -20 }
+        ));
+    }
+
+    #[test]
+    fn parse_color_change() {
+        let data = [0x0A, 0x14, 0x80, 0x01, 0x05, 0x03];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(cmds[0], StitchCommand::Stitch { .. }));
+        assert!(matches!(cmds[1], StitchCommand::ColorChange));
+        assert!(matches!(cmds[2], StitchCommand::Stitch { dx: 5, dy: 3 }));
+    }
+
+    #[test]
+    fn parse_jump() {
+        let data = [0x80, 0x04, 0x0A, 0x14];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(
+            cmds[0],
+            StitchCommand::Jump { dx: 10, dy: 20 }
+        ));
+    }
+
+    #[test]
+    fn parse_trim() {
+        let data = [0x0A, 0x14, 0x80, 0x80, 0x05, 0x03];
+        let cmds = parse(&data).unwrap();
+        assert!(matches!(cmds[1], StitchCommand::Trim));
+    }
+}
diff --git a/rustitch/src/format.rs b/rustitch/src/format.rs
new file mode 100644
index 0000000..a07e429
--- /dev/null
+++ b/rustitch/src/format.rs
@@ -0,0 +1,34 @@
+use std::path::Path;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Format {
+    Pes,
+    Dst,
+    Exp,
+    Jef,
+    Vp3,
+}
+
+/// Detect format from file content (magic bytes).
+pub fn detect_from_bytes(data: &[u8]) -> Option<Format> {
+    if data.len() >= 4 && &data[0..4] == b"#PES" {
+        return Some(Format::Pes);
+    }
+    if data.len() >= 5 && &data[0..5] == b"%vsm%" {
+        return Some(Format::Vp3);
+    }
+    None
+}
+
+/// Detect format from file extension.
+pub fn detect_from_extension(path: &Path) -> Option<Format> {
+    let ext = path.extension()?.to_str()?;
+    match ext.to_ascii_lowercase().as_str() {
+        "pes" => Some(Format::Pes),
+        "dst" => Some(Format::Dst),
+        "exp" => Some(Format::Exp),
+        "jef" => Some(Format::Jef),
+        "vp3" => Some(Format::Vp3),
+        _ => None,
+    }
+}
diff --git a/rustitch/src/jef/mod.rs b/rustitch/src/jef/mod.rs
new file mode 100644
index 0000000..bcedee5
--- /dev/null
+++ b/rustitch/src/jef/mod.rs
@@ -0,0 +1,173 @@
+mod palette;
+
+use crate::error::Error;
+use crate::types::{ResolvedDesign, StitchCommand};
+use palette::JEF_PALETTE;
+
+/// Parse a JEF (Janome) file from raw bytes into stitch commands and color info.
+///
+/// JEF header layout (little-endian):
+///   0..4:   stitch data offset (u32)
+///   4..8:   flags/format indicator
+///   24..28: color count (u32)
+///   28..32: stitch count (u32)
+///   116+:   color table (each entry: i32 palette index)
+///
+/// Stitch data: 2 bytes per stitch (signed i8 dx, dy).
+/// Control codes: 0x80 0x01 = color change, 0x80 0x02 = jump, 0x80 0x10 = end.
+pub fn parse(data: &[u8]) -> Result<(Vec<StitchCommand>, Vec<(u8, u8, u8)>), Error> {
+    if data.len() < 116 {
+        return Err(Error::TooShort {
+            expected: 116,
+            actual: data.len(),
+        });
+    }
+
+    let stitch_offset = read_u32_le(data, 0) as usize;
+    let color_count = read_u32_le(data, 24) as usize;
+
+    if stitch_offset > data.len() {
+        return Err(Error::InvalidHeader(format!(
+            "stitch data offset {} exceeds file length {}",
+            stitch_offset,
+            data.len()
+        )));
+    }
+
+    // Read color table starting at offset 116
+    let color_table_start = 116;
+    let mut colors = Vec::with_capacity(color_count);
+    for i in 0..color_count {
+        let entry_offset = color_table_start + i * 4;
+        if entry_offset + 4 > data.len() {
+            break;
+        }
+        let idx = read_i32_le(data, entry_offset);
+        let palette_idx = if idx >= 0 && (idx as usize) < JEF_PALETTE.len() {
+            idx as usize
+        } else {
+            0
+        };
+        colors.push(JEF_PALETTE[palette_idx]);
+    }
+
+    if colors.is_empty() {
+        colors.push((0, 0, 0));
+    }
+
+    // Parse stitch data
+    let stitch_data = &data[stitch_offset..];
+    let commands = decode_stitches(stitch_data)?;
+
+    Ok((commands, colors))
+}
+
+fn decode_stitches(data: &[u8]) -> Result<Vec<StitchCommand>, Error> {
+    let mut commands = Vec::new();
+    let mut i = 0;
+
+    while i + 1 < data.len() {
+        let b1 = data[i];
+        let b2 = data[i + 1];
+
+        if b1 == 0x80 {
+            match b2 {
+                0x01 => {
+                    commands.push(StitchCommand::ColorChange);
+                    i += 2;
+                }
+                0x02 => {
+                    // Jump: next 2 bytes are movement
+                    i += 2;
+                    if i + 1 >= data.len() {
+                        break;
+                    }
+                    let dx = data[i] as i8 as i16;
+                    let dy = -(data[i + 1] as i8 as i16);
+                    commands.push(StitchCommand::Jump { dx, dy });
+                    i += 2;
+                }
+                0x10 => {
+                    commands.push(StitchCommand::End);
+                    break;
+                }
+                _ => {
+                    i += 2;
+                }
+            }
+        } else {
+            let dx = b1 as i8 as i16;
+            let dy = -(b2 as i8 as i16);
+            commands.push(StitchCommand::Stitch { dx, dy });
+            i += 2;
+        }
+    }
+
+    if commands.is_empty() {
+        return Err(Error::NoStitchData);
+    }
+
+    if !matches!(commands.last(), Some(StitchCommand::End)) {
+        commands.push(StitchCommand::End);
+    }
+
+    Ok(commands)
+}
+
+/// Parse a JEF file and resolve to a renderable design.
+pub fn parse_and_resolve(data: &[u8]) -> Result<ResolvedDesign, Error> {
+    let (commands, colors) = parse(data)?;
+    crate::resolve::resolve(&commands, colors)
+}
+
+fn read_u32_le(data: &[u8], offset: usize) -> u32 {
+    u32::from_le_bytes([
+        data[offset],
+        data[offset + 1],
+        data[offset + 2],
+        data[offset + 3],
+    ])
+}
+
+fn read_i32_le(data: &[u8], offset: usize) -> i32 {
+    i32::from_le_bytes([
+        data[offset],
+        data[offset + 1],
+        data[offset + 2],
+        data[offset + 3],
+    ])
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn decode_simple_stitches() {
+        let data = [0x0A, 0x14, 0x05, 0x03, 0x80, 0x10];
+        let cmds = decode_stitches(&data).unwrap();
+        assert!(matches!(
+            cmds[0],
+            StitchCommand::Stitch { dx: 10, dy: -20 }
+        ));
+        assert!(matches!(cmds[1], StitchCommand::Stitch { dx: 5, dy: -3 }));
+        assert!(matches!(cmds[2], StitchCommand::End));
+    }
+
+    #[test]
+    fn decode_color_change() {
+        let data = [0x0A, 0x14, 0x80, 0x01, 0x05, 0x03, 0x80, 0x10];
+        let cmds = decode_stitches(&data).unwrap();
+        assert!(matches!(cmds[1], StitchCommand::ColorChange));
+    }
+
+    #[test]
+    fn decode_jump() {
+        let data = [0x80, 0x02, 0x0A, 0x14, 0x80, 0x10];
+        let cmds = decode_stitches(&data).unwrap();
+        assert!(matches!(
+            cmds[0],
+            StitchCommand::Jump { dx: 10, dy: -20 }
+        ));
+    }
+}
diff --git a/rustitch/src/jef/palette.rs b/rustitch/src/jef/palette.rs
new file mode 100644
index 0000000..0b91fbc
--- /dev/null
+++ b/rustitch/src/jef/palette.rs
@@ -0,0 +1,82 @@
+/// Janome thread color palette (78 entries).
+/// Index 0 is a fallback; indices 1-77 correspond to standard Janome thread colors.
+pub const JEF_PALETTE: [(u8, u8, u8); 78] = [
+    (0, 0, 0),       //  0: Unknown / Black
+    (0, 0, 0),       //  1: Black
+    (255, 255, 255), //  2: White
+    (255, 255, 23),  //  3: Yellow
+    (250, 160, 96),  //  4: Orange
+    (92, 118, 73),   //  5: Olive Green
+    (64, 192, 48),   //  6: Green
+    (101, 194, 200), //  7: Sky Blue
+    (172, 128, 190), //  8: Purple
+    (245, 188, 203), //  9: Pink
+    (255, 0, 0),     // 10: Red
+    (192, 128, 0),   // 11: Brown
+    (0, 0, 240),     // 12: Blue
+    (228, 195, 93),  // 13: Gold
+    (165, 42, 42),   // 14: Dark Brown
+    (213, 176, 212), // 15: Pale Violet
+    (252, 242, 148), // 16: Pale Yellow
+    (240, 208, 192), // 17: Pale Pink
+    (255, 192, 0),   // 18: Peach
+    (201, 164, 128), // 19: Beige
+    (155, 61, 75),   // 20: Wine Red
+    (160, 184, 204), // 21: Pale Sky Blue
+    (127, 194, 28),  // 22: Yellow Green
+    (185, 185, 185), // 23: Silver Gray
+    (160, 160, 160), // 24: Gray
+    (152, 214, 189), // 25: Pale Aqua
+    (184, 240, 240), // 26: Baby Blue
+    (54, 139, 160),  // 27: Powder Blue
+    (79, 131, 171),  // 28: Bright Blue
+    (56, 106, 145),  // 29: Slate Blue
+    (0, 32, 107),    // 30: Navy Blue
+    (229, 197, 202), // 31: Salmon Pink
+    (249, 103, 107), // 32: Coral
+    (227, 49, 31),   // 33: Burnt Orange
+    (226, 161, 136), // 34: Cinnamon
+    (181, 148, 116), // 35: Umber
+    (228, 207, 153), // 36: Blond
+    (225, 203, 0),   // 37: Sunflower
+    (225, 173, 212), // 38: Orchid Pink
+    (195, 0, 126),   // 39: Peony
+    (128, 0, 75),    // 40: Burgundy
+    (160, 96, 176),  // 41: Royal Purple
+    (192, 64, 32),   // 42: Cardinal Red
+    (202, 224, 192), // 43: Opal Green
+    (137, 152, 86),  // 44: Moss Green
+    (0, 170, 0),     // 45: Meadow Green
+    (33, 138, 33),   // 46: Dark Green
+    (93, 174, 148),  // 47: Aquamarine
+    (76, 191, 143),  // 48: Emerald Green
+    (0, 119, 114),   // 49: Peacock Green
+    (112, 112, 112), // 50: Dark Gray
+    (242, 255, 255), // 51: Ivory White
+    (177, 88, 24),   // 52: Hazel
+    (203, 138, 7),   // 53: Toast
+    (247, 146, 123), // 54: Salmon
+    (152, 105, 45),  // 55: Cocoa Brown
+    (162, 113, 72),  // 56: Sienna
+    (123, 85, 74),   // 57: Sepia
+    (79, 57, 70),    // 58: Dark Sepia
+    (82, 58, 151),   // 59: Violet Blue
+    (0, 0, 160),     // 60: Blue Ink
+    (0, 150, 222),   // 61: Solar Blue
+    (178, 221, 83),  // 62: Green Dust
+    (250, 143, 187), // 63: Crimson
+    (222, 100, 158), // 64: Floral Pink
+    (181, 80, 102),  // 65: Wine
+    (94, 87, 71),    // 66: Olive Drab
+    (76, 136, 31),   // 67: Meadow
+    (228, 220, 121), // 68: Mustard
+    (203, 138, 26),  // 69: Yellow Ochre
+    (198, 170, 66),  // 70: Old Gold
+    (236, 176, 44),  // 71: Honeydew
+    (248, 128, 64),  // 72: Tangerine
+    (255, 229, 5),   // 73: Canary Yellow
+    (250, 122, 122), // 74: Vermilion
+    (107, 224, 0),   // 75: Bright Green
+    (56, 108, 174),  // 76: Ocean Blue
+    (227, 196, 180), // 77: Beige Gray
+];
diff --git a/rustitch/src/lib.rs b/rustitch/src/lib.rs
index aa9ad3b..a51b4c2 100644
--- a/rustitch/src/lib.rs
+++ b/rustitch/src/lib.rs
@@ -1,12 +1,37 @@
-pub mod pes;
-mod render;
+pub mod error;
+pub mod format;
+pub mod palette;
+pub mod types;
 
+pub mod pes;
+
+mod render;
+mod resolve;
+
+pub use error::Error;
+pub use format::Format;
 pub use render::render_thumbnail;
+pub use types::{BoundingBox, ResolvedDesign, StitchCommand, StitchSegment};
 
 /// Parse a PES file and render a thumbnail PNG of the given size.
-pub fn thumbnail(pes_data: &[u8], size: u32) -> Result<Vec<u8>, pes::Error> {
+pub fn thumbnail(pes_data: &[u8], size: u32) -> Result<Vec<u8>, Error> {
     let design = pes::parse(pes_data)?;
     let resolved = pes::resolve(&design)?;
-    let png_bytes = render::render_thumbnail(&resolved, size)?;
-    Ok(png_bytes)
+    render::render_thumbnail(&resolved, size)
+}
+
+/// Parse any supported format and render a thumbnail PNG.
+pub fn thumbnail_format(data: &[u8], size: u32, fmt: Format) -> Result<Vec<u8>, Error> {
+    let resolved = parse_and_resolve(data, fmt)?;
+    render::render_thumbnail(&resolved, size)
+}
+
+fn parse_and_resolve(data: &[u8], fmt: Format) -> Result<ResolvedDesign, Error> {
+    match fmt {
+        Format::Pes => {
+            let design = pes::parse(data)?;
+            pes::resolve(&design)
+        }
+        _ => Err(Error::UnsupportedFormat),
+    }
 }
diff --git a/rustitch/src/palette.rs b/rustitch/src/palette.rs
new file mode 100644
index 0000000..0c3fd2f
--- /dev/null
+++ b/rustitch/src/palette.rs
@@ -0,0 +1,93 @@
+/// Brother PEC thread color palette (65 entries).
+/// Index 0 is a fallback; indices 1-64 correspond to standard Brother thread colors.
+pub const PEC_PALETTE: [(u8, u8, u8); 65] = [
+    (0, 0, 0),       //  0: Unknown
+    (14, 31, 124),   //  1: Prussian Blue
+    (10, 85, 163),   //  2: Blue
+    (0, 135, 119),   //  3: Teal Green
+    (75, 107, 175),  //  4: Cornflower Blue
+    (237, 23, 31),   //  5: Red
+    (209, 92, 0),    //  6: Reddish Brown
+    (145, 54, 151),  //  7: Magenta
+    (228, 154, 203), //  8: Light Lilac
+    (145, 95, 172),  //  9: Lilac
+    (158, 214, 125), // 10: Mint Green
+    (232, 169, 0),   // 11: Deep Gold
+    (254, 186, 53),  // 12: Orange
+    (255, 255, 0),   // 13: Yellow
+    (112, 188, 31),  // 14: Lime Green
+    (186, 152, 0),   // 15: Brass
+    (168, 168, 168), // 16: Silver
+    (125, 111, 0),   // 17: Russet Brown
+    (255, 255, 179), // 18: Cream Brown
+    (79, 85, 86),    // 19: Pewter
+    (0, 0, 0),       // 20: Black
+    (11, 61, 145),   // 21: Ultramarine
+    (119, 1, 118),   // 22: Royal Purple
+    (41, 49, 51),    // 23: Dark Gray
+    (42, 19, 1),     // 24: Dark Brown
+    (246, 74, 138),  // 25: Deep Rose
+    (178, 118, 36),  // 26: Light Brown
+    (252, 187, 197), // 27: Salmon Pink
+    (254, 55, 15),   // 28: Vermilion
+    (240, 240, 240), // 29: White
+    (106, 28, 138),  // 30: Violet
+    (168, 221, 196), // 31: Seacrest
+    (37, 132, 187),  // 32: Sky Blue
+    (254, 179, 67),  // 33: Pumpkin
+    (255, 243, 107), // 34: Cream Yellow
+    (208, 166, 96),  // 35: Khaki
+    (209, 84, 0),    // 36: Clay Brown
+    (102, 186, 73),  // 37: Leaf Green
+    (19, 74, 70),    // 38: Peacock Blue
+    (135, 135, 135), // 39: Gray
+    (216, 204, 198), // 40: Warm Gray
+    (67, 86, 7),     // 41: Dark Olive
+    (253, 217, 222), // 42: Flesh Pink
+    (249, 147, 188), // 43: Pink
+    (0, 56, 34),     // 44: Deep Green
+    (178, 175, 212), // 45: Lavender
+    (104, 106, 176), // 46: Wisteria Violet
+    (239, 227, 185), // 47: Beige
+    (247, 56, 102),  // 48: Carmine
+    (181, 75, 100),  // 49: Amber Red
+    (19, 43, 26),    // 50: Olive Green
+    (199, 1, 86),    // 51: Dark Fuchsia
+    (254, 158, 50),  // 52: Tangerine
+    (168, 222, 235), // 53: Light Blue
+    (0, 103, 62),    // 54: Emerald Green
+    (78, 41, 144),   // 55: Purple
+    (47, 126, 32),   // 56: Moss Green
+    (255, 204, 204), // 57: Flesh Pink
+    (255, 217, 17),  // 58: Harvest Gold
+    (9, 91, 166),    // 59: Electric Blue
+    (240, 249, 112), // 60: Lemon Yellow
+    (227, 243, 91),  // 61: Fresh Green
+    (255, 153, 0),   // 62: Orange
+    (255, 240, 141), // 63: Cream Yellow
+    (255, 200, 200), // 64: Applique
+];
+
+/// Default high-contrast palette for formats without embedded color info (DST, EXP).
+/// Colors cycle on each color change.
+pub const DEFAULT_PALETTE: [(u8, u8, u8); 12] = [
+    (0, 0, 0),      // Black
+    (237, 23, 31),  // Red
+    (10, 85, 163),  // Blue
+    (0, 135, 119),  // Teal Green
+    (254, 186, 53), // Orange
+    (145, 54, 151), // Magenta
+    (112, 188, 31), // Lime Green
+    (42, 19, 1),    // Dark Brown
+    (37, 132, 187), // Sky Blue
+    (246, 74, 138), // Deep Rose
+    (186, 152, 0),  // Brass
+    (106, 28, 138), // Violet
+];
+
+/// Build a color list for `n` thread slots by cycling through `DEFAULT_PALETTE`.
+pub fn default_colors(n: usize) -> Vec<(u8, u8, u8)> {
+    (0..n)
+        .map(|i| DEFAULT_PALETTE[i % DEFAULT_PALETTE.len()])
+        .collect()
+}
diff --git a/rustitch/src/pes/header.rs b/rustitch/src/pes/header.rs
index 60a215e..b9b84dc 100644
--- a/rustitch/src/pes/header.rs
+++ b/rustitch/src/pes/header.rs
@@ -1,4 +1,4 @@
-use super::Error;
+use crate::error::Error;
 
 #[derive(Debug)]
 pub struct PesHeader {
@@ -18,7 +18,7 @@ pub fn parse_header(data: &[u8]) -> Result<PesHeader, Error> {
     if magic != b"#PES" {
         let mut m = [0u8; 4];
         m.copy_from_slice(magic);
-        return Err(Error::InvalidMagic(m));
+        return Err(Error::InvalidPesMagic(m));
     }
 
     let mut version = [0u8; 4];
@@ -41,7 +41,6 @@ mod tests {
         let mut data = vec![0u8; 20];
         data[0..4].copy_from_slice(b"#PES");
         data[4..8].copy_from_slice(b"0001");
-        // PEC offset = 16 (little-endian)
         data[8..12].copy_from_slice(&16u32.to_le_bytes());
 
         let header = parse_header(&data).unwrap();
@@ -53,7 +52,7 @@ mod tests {
     fn reject_invalid_magic() {
         let data = b"NOTPES0001\x10\x00\x00\x00";
         let err = parse_header(data).unwrap_err();
-        assert!(matches!(err, Error::InvalidMagic(_)));
+        assert!(matches!(err, Error::InvalidPesMagic(_)));
     }
 
     #[test]
diff --git a/rustitch/src/pes/mod.rs b/rustitch/src/pes/mod.rs
index a305109..44e6c37 100644
--- a/rustitch/src/pes/mod.rs
+++ b/rustitch/src/pes/mod.rs
@@ -1,30 +1,13 @@
 mod header;
-mod palette;
 mod pec;
 
 pub use header::PesHeader;
-pub use palette::PEC_PALETTE;
-pub use pec::{PecHeader, StitchCommand};
+pub use pec::PecHeader;
 
-use thiserror::Error;
-
-#[derive(Debug, Error)]
-pub enum Error {
-    #[error("invalid PES magic: expected #PES, got {0:?}")]
-    InvalidMagic([u8; 4]),
-    #[error("file too short: need {expected} bytes, got {actual}")]
-    TooShort { expected: usize, actual: usize },
-    #[error("invalid PEC offset: {0} exceeds file length {1}")]
-    InvalidPecOffset(u32, usize),
-    #[error("no stitch data found")]
-    NoStitchData,
-    #[error("empty design: no stitch segments produced")]
-    EmptyDesign,
-    #[error("render error: {0}")]
-    Render(String),
-    #[error("PNG encoding error: {0}")]
-    PngEncode(#[from] png::EncodingError),
-}
+// Re-export shared types for backward compatibility
+pub use crate::error::Error;
+pub use crate::palette::PEC_PALETTE;
+pub use crate::types::{BoundingBox, ResolvedDesign, StitchCommand, StitchSegment};
 
 pub struct PesDesign {
     pub header: PesHeader,
@@ -32,27 +15,6 @@ pub struct PesDesign {
     pub commands: Vec<StitchCommand>,
 }
 
-pub struct StitchSegment {
-    pub x0: f32,
-    pub y0: f32,
-    pub x1: f32,
-    pub y1: f32,
-    pub color_index: usize,
-}
-
-pub struct BoundingBox {
-    pub min_x: f32,
-    pub max_x: f32,
-    pub min_y: f32,
-    pub max_y: f32,
-}
-
-pub struct ResolvedDesign {
-    pub segments: Vec<StitchSegment>,
-    pub colors: Vec<(u8, u8, u8)>,
-    pub bounds: BoundingBox,
-}
-
 /// Parse a PES file from raw bytes.
 pub fn parse(data: &[u8]) -> Result<PesDesign, Error> {
     let header = header::parse_header(data)?;
@@ -73,66 +35,8 @@ pub fn parse(data: &[u8]) -> Result<PesDesign, Error> {
     })
 }
 
-/// Convert parsed commands into renderable segments with absolute coordinates.
+/// Convert parsed PES design into renderable segments with absolute coordinates.
 pub fn resolve(design: &PesDesign) -> Result<ResolvedDesign, Error> {
-    let mut segments = Vec::new();
-    let mut x: f32 = 0.0;
-    let mut y: f32 = 0.0;
-    let mut color_idx: usize = 0;
-    let mut pen_down = true;
-
-    for cmd in &design.commands {
-        match cmd {
-            StitchCommand::Stitch { dx, dy } => {
-                let nx = x + *dx as f32;
-                let ny = y + *dy as f32;
-                if pen_down {
-                    segments.push(StitchSegment {
-                        x0: x,
-                        y0: y,
-                        x1: nx,
-                        y1: ny,
-                        color_index: color_idx,
-                    });
-                }
-                x = nx;
-                y = ny;
-                pen_down = true;
-            }
-            StitchCommand::Jump { dx, dy } => {
-                x += *dx as f32;
-                y += *dy as f32;
-                pen_down = false;
-            }
-            StitchCommand::Trim => {
-                pen_down = false;
-            }
-            StitchCommand::ColorChange => {
-                color_idx += 1;
-                pen_down = false;
-            }
-            StitchCommand::End => break,
-        }
-    }
-
-    if segments.is_empty() {
-        return Err(Error::EmptyDesign);
-    }
-
-    // Compute bounding box
-    let mut min_x = f32::MAX;
-    let mut max_x = f32::MIN;
-    let mut min_y = f32::MAX;
-    let mut max_y = f32::MIN;
-
-    for seg in &segments {
-        min_x = min_x.min(seg.x0).min(seg.x1);
-        max_x = max_x.max(seg.x0).max(seg.x1);
-        min_y = min_y.min(seg.y0).min(seg.y1);
-        max_y = max_y.max(seg.y0).max(seg.y1);
-    }
-
-    // Resolve colors from palette indices
     let colors: Vec<(u8, u8, u8)> = design
         .pec_header
         .color_indices
@@ -143,14 +47,5 @@ pub fn resolve(design: &PesDesign) -> Result<ResolvedDesign, Error> {
         })
         .collect();
 
-    Ok(ResolvedDesign {
-        segments,
-        colors,
-        bounds: BoundingBox {
-            min_x,
-            max_x,
-            min_y,
-            max_y,
-        },
-    })
+    crate::resolve::resolve(&design.commands, colors)
 }
diff --git a/rustitch/src/pes/palette.rs b/rustitch/src/pes/palette.rs
index ea6002b..423c1bc 100644
--- a/rustitch/src/pes/palette.rs
+++ b/rustitch/src/pes/palette.rs
@@ -1,69 +1,2 @@
-/// Brother PEC thread color palette (65 entries).
-/// Index 0 is a fallback; indices 1–64 correspond to standard Brother thread colors.
-pub const PEC_PALETTE: [(u8, u8, u8); 65] = [
-    (0, 0, 0),       //  0: Unknown
-    (14, 31, 124),   //  1: Prussian Blue
-    (10, 85, 163),   //  2: Blue
-    (0, 135, 119),   //  3: Teal Green
-    (75, 107, 175),  //  4: Cornflower Blue
-    (237, 23, 31),   //  5: Red
-    (209, 92, 0),    //  6: Reddish Brown
-    (145, 54, 151),  //  7: Magenta
-    (228, 154, 203), //  8: Light Lilac
-    (145, 95, 172),  //  9: Lilac
-    (158, 214, 125), // 10: Mint Green
-    (232, 169, 0),   // 11: Deep Gold
-    (254, 186, 53),  // 12: Orange
-    (255, 255, 0),   // 13: Yellow
-    (112, 188, 31),  // 14: Lime Green
-    (186, 152, 0),   // 15: Brass
-    (168, 168, 168), // 16: Silver
-    (125, 111, 0),   // 17: Russet Brown
-    (255, 255, 179), // 18: Cream Brown
-    (79, 85, 86),    // 19: Pewter
-    (0, 0, 0),       // 20: Black
-    (11, 61, 145),   // 21: Ultramarine
-    (119, 1, 118),   // 22: Royal Purple
-    (41, 49, 51),    // 23: Dark Gray
-    (42, 19, 1),     // 24: Dark Brown
-    (246, 74, 138),  // 25: Deep Rose
-    (178, 118, 36),  // 26: Light Brown
-    (252, 187, 197), // 27: Salmon Pink
-    (254, 55, 15),   // 28: Vermilion
-    (240, 240, 240), // 29: White
-    (106, 28, 138),  // 30: Violet
-    (168, 221, 196), // 31: Seacrest
-    (37, 132, 187),  // 32: Sky Blue
-    (254, 179, 67),  // 33: Pumpkin
-    (255, 243, 107), // 34: Cream Yellow
-    (208, 166, 96),  // 35: Khaki
-    (209, 84, 0),    // 36: Clay Brown
-    (102, 186, 73),  // 37: Leaf Green
-    (19, 74, 70),    // 38: Peacock Blue
-    (135, 135, 135), // 39: Gray
-    (216, 204, 198), // 40: Warm Gray
-    (67, 86, 7),     // 41: Dark Olive
-    (253, 217, 222), // 42: Flesh Pink
-    (249, 147, 188), // 43: Pink
-    (0, 56, 34),     // 44: Deep Green
-    (178, 175, 212), // 45: Lavender
-    (104, 106, 176), // 46: Wisteria Violet
-    (239, 227, 185), // 47: Beige
-    (247, 56, 102),  // 48: Carmine
-    (181, 75, 100),  // 49: Amber Red
-    (19, 43, 26),    // 50: Olive Green
-    (199, 1, 86),    // 51: Dark Fuchsia
-    (254, 158, 50),  // 52: Tangerine
-    (168, 222, 235), // 53: Light Blue
-    (0, 103, 62),    // 54: Emerald Green
-    (78, 41, 144),   // 55: Purple
-    (47, 126, 32),   // 56: Moss Green
-    (255, 204, 204), // 57: Flesh Pink
-    (255, 217, 17),  // 58: Harvest Gold
-    (9, 91, 166),    // 59: Electric Blue
-    (240, 249, 112), // 60: Lemon Yellow
-    (227, 243, 91),  // 61: Fresh Green
-    (255, 153, 0),   // 62: Orange
-    (255, 240, 141), // 63: Cream Yellow
-    (255, 200, 200), // 64: Applique
-];
+// Re-export from crate root for backward compatibility
+pub use crate::palette::PEC_PALETTE;
diff --git a/rustitch/src/pes/pec.rs b/rustitch/src/pes/pec.rs
index b3c95d1..25cf2dd 100644
--- a/rustitch/src/pes/pec.rs
+++ b/rustitch/src/pes/pec.rs
@@ -1,4 +1,5 @@
-use super::Error;
+use crate::error::Error;
+use crate::types::StitchCommand;
 
 pub struct PecHeader {
     pub label: String,
@@ -6,19 +7,9 @@ pub struct PecHeader {
     pub color_indices: Vec<u8>,
 }
 
-#[derive(Debug, Clone)]
-pub enum StitchCommand {
-    Stitch { dx: i16, dy: i16 },
-    Jump { dx: i16, dy: i16 },
-    Trim,
-    ColorChange,
-    End,
-}
-
 /// Parse the PEC header starting at the PEC section offset.
 /// Returns the header and the byte offset (relative to pec_data start) where stitch data begins.
 pub fn parse_pec_header(pec_data: &[u8]) -> Result<(PecHeader, usize), Error> {
-    // PEC section starts with "LA:" label field (19 bytes total)
     if pec_data.len() < 532 {
         return Err(Error::TooShort {
             expected: 532,
@@ -26,57 +17,15 @@ pub fn parse_pec_header(pec_data: &[u8]) -> Result<(PecHeader, usize), Error> {
         });
     }
 
-    // Label: bytes 0..19, starts with "LA:"
     let label_raw = &pec_data[3..19];
     let label = std::str::from_utf8(label_raw)
         .unwrap_or("")
         .trim()
         .to_string();
 
-    // Color count at offset 48 from PEC start
     let color_count = pec_data[48] + 1;
-
-    // Color indices follow at offset 49
     let color_indices: Vec<u8> = pec_data[49..49 + color_count as usize].to_vec();
 
-    // Stitch data starts at offset 532 from PEC section start
-    // (48 bytes header + 463 bytes padding/thumbnail = 512, plus 20 bytes of graphic data = 532)
-    // Actually the standard offset is 512 + the two thumbnail sections.
-    // The typical approach: skip to offset 48 + 1 + color_count + padding to 512, then skip thumbnails.
-    // Simplified: PEC stitch data offset = 512 + 20 (for the stitch data header that contains the graphic offsets)
-    // A more robust approach: read the stitch data offset from the header.
-
-    // At PEC offset + 20..24 there are two u16 LE values for the thumbnail image offsets.
-    // The stitch data typically starts after a fixed 532-byte header region.
-    // Let's use the more standard approach from libpes:
-    // Offset 514-515 (relative to PEC start): thumbnail1 image offset (u16 LE, relative)
-    // But the simplest reliable approach is to find the stitch data after the fixed header.
-
-    // The standard PEC header is 512 bytes, followed by two thumbnail images.
-    // Thumbnail 1: 6 bytes wide × 38 bytes high = 228 bytes (48×38 pixel, 1bpp padded)
-    // Actually, typical PEC has: after the 512-byte block, there are two graphics sections.
-    // The stitch data starts after those graphics.
-    //
-    // More robust: bytes 514..516 give the thumbnail offset (little-endian u16).
-    // We can derive stitch data from there, but let's use the standard fixed sizes.
-    // Thumbnail 1: at offset 512, size = ceil(width*2/8) * height, with default 48×38 = 6*38=228
-    // Thumbnail 2: at offset 512+228=740, size = ceil(width*2/8) * height, default 96×76=12*76=912
-    // Stitch data at: 512 + 228 + 912 = 1652? That doesn't seem right.
-    //
-    // Actually from libpes wiki: PEC header is 20 bytes, then color info, then padding to
-    // reach a 512-byte boundary. At byte 512 is the beginning of the PEC graphic section.
-    // After the graphics come the stitch data. But graphic sizes vary.
-    //
-    // The correct approach: at PEC_start + 514 (bytes 514-515), read a u16 LE which gives
-    // the absolute offset from PEC_start to the first thumbnail. Then after thumbnails come stitches.
-    // BUT actually, the standard approach used by most parsers is simpler:
-    //
-    // pyembroidery approach: seek to PEC_start + 532, that's where stitch data starts.
-    // The 532 = 512 + 20 (20 bytes for graphic header).
-    //
-    // Let's verify: pyembroidery's PecReader reads stitches starting 532 bytes after PEC start.
-    // Let's go with 532.
-
     let stitch_data_offset = 532;
 
     if pec_data.len() <= stitch_data_offset {
@@ -101,31 +50,26 @@ pub fn decode_stitches(data: &[u8]) -> Result<Vec<StitchCommand>, Error> {
     while i < data.len() {
         let b1 = data[i];
 
-        // End marker
         if b1 == 0xFF {
             commands.push(StitchCommand::End);
             break;
         }
 
-        // Color change
         if b1 == 0xFE {
             commands.push(StitchCommand::ColorChange);
-            i += 2; // skip the 0xFE and the following byte (typically 0xB0)
+            i += 2;
             continue;
         }
 
-        // Parse dx
         let (dx, dx_flags, bytes_dx) = decode_coordinate(data, i)?;
         i += bytes_dx;
 
-        // Parse dy
         let (dy, dy_flags, bytes_dy) = decode_coordinate(data, i)?;
         i += bytes_dy;
 
         let flags = dx_flags | dy_flags;
 
         if flags & 0x20 != 0 {
-            // Trim + jump
             commands.push(StitchCommand::Trim);
             commands.push(StitchCommand::Jump { dx, dy });
         } else if flags & 0x10 != 0 {
@@ -155,7 +99,6 @@ fn decode_coordinate(data: &[u8], pos: usize) -> Result<(i16, u8, usize), Error>
     let b = data[pos];
 
     if b & 0x80 != 0 {
-        // Extended 12-bit encoding (2 bytes)
         if pos + 1 >= data.len() {
             return Err(Error::TooShort {
                 expected: pos + 2,
@@ -163,7 +106,7 @@ fn decode_coordinate(data: &[u8], pos: usize) -> Result<(i16, u8, usize), Error>
             });
         }
         let b2 = data[pos + 1];
-        let flags = b & 0x70; // bits 6-4 for jump/trim flags
+        let flags = b & 0x70;
         let raw = (((b & 0x0F) as u16) << 8) | (b2 as u16);
         let value = if raw > 0x7FF {
             raw as i16 - 0x1000
@@ -172,7 +115,6 @@ fn decode_coordinate(data: &[u8], pos: usize) -> Result<(i16, u8, usize), Error>
         };
         Ok((value, flags, 2))
     } else {
-        // 7-bit encoding (1 byte)
         let value = if b > 0x3F { b as i16 - 0x80 } else { b as i16 };
         Ok((value, 0, 1))
     }
@@ -192,7 +134,6 @@ mod tests {
 
     #[test]
     fn decode_simple_stitch() {
-        // dx=10 (0x0A), dy=20 (0x14), then end
         let data = [0x0A, 0x14, 0xFF];
         let cmds = decode_stitches(&data).unwrap();
         assert_eq!(cmds.len(), 2);
@@ -207,7 +148,6 @@ mod tests {
 
     #[test]
     fn decode_negative_7bit() {
-        // dx=0x50 (80 decimal, > 0x3F so value = 80-128 = -48), dy=0x60 (96-128=-32), end
         let data = [0x50, 0x60, 0xFF];
         let cmds = decode_stitches(&data).unwrap();
         match &cmds[0] {
@@ -229,9 +169,6 @@ mod tests {
 
     #[test]
     fn decode_extended_12bit() {
-        // Extended dx: high bit set, flags=0x10 (jump), value = 0x100 = 256
-        // byte1 = 0x80 | 0x10 | 0x01 = 0x91, byte2 = 0x00 -> raw = 0x100 = 256
-        // dy: simple 0x05 = 5
         let data = [0x91, 0x00, 0x05, 0xFF];
         let cmds = decode_stitches(&data).unwrap();
         assert!(matches!(cmds[0], StitchCommand::Jump { dx: 256, dy: 5 }));
@@ -239,8 +176,6 @@ mod tests {
 
     #[test]
     fn decode_trim_jump() {
-        // dx with trim flag (0x20): byte1 = 0x80 | 0x20 | 0x00 = 0xA0, byte2 = 0x0A -> raw=10
-        // dy: simple 0x05
         let data = [0xA0, 0x0A, 0x05, 0xFF];
         let cmds = decode_stitches(&data).unwrap();
         assert!(matches!(cmds[0], StitchCommand::Trim));
diff --git a/rustitch/src/render.rs b/rustitch/src/render.rs
index a6621a0..f2e59f8 100644
--- a/rustitch/src/render.rs
+++ b/rustitch/src/render.rs
@@ -1,6 +1,7 @@
 use tiny_skia::{LineCap, Paint, PathBuilder, Pixmap, Stroke, Transform};
 
-use crate::pes::{Error, ResolvedDesign};
+use crate::error::Error;
+use crate::types::ResolvedDesign;
 
 /// Render a resolved embroidery design to a PNG image of the given size.
 pub fn render_thumbnail(design: &ResolvedDesign, size: u32) -> Result<Vec<u8>, Error> {
@@ -23,7 +24,6 @@ pub fn render_thumbnail(design: &ResolvedDesign, size: u32) -> Result<Vec<u8>, E
 
     let line_width = (scale * 0.3).max(1.0);
 
-    // Group segments by color index and draw each group
     let max_color = design
         .segments
         .iter()
@@ -82,7 +82,6 @@ fn encode_png(pixmap: &Pixmap) -> Result<Vec<u8>, Error> {
     let height = pixmap.height();
     let src = pixmap.data();
 
-    // Unpremultiply alpha
     let mut data = Vec::with_capacity(src.len());
     for chunk in src.chunks_exact(4) {
         let (r, g, b, a) = (chunk[0], chunk[1], chunk[2], chunk[3]);
diff --git a/rustitch/src/resolve.rs b/rustitch/src/resolve.rs
new file mode 100644
index 0000000..bd4371f
--- /dev/null
+++ b/rustitch/src/resolve.rs
@@ -0,0 +1,75 @@
+use crate::error::Error;
+use crate::types::{BoundingBox, ResolvedDesign, StitchCommand, StitchSegment};
+
+/// Convert parsed stitch commands into renderable segments with absolute coordinates.
+pub fn resolve(
+    commands: &[StitchCommand],
+    colors: Vec<(u8, u8, u8)>,
+) -> Result<ResolvedDesign, Error> {
+    let mut segments = Vec::new();
+    let mut x: f32 = 0.0;
+    let mut y: f32 = 0.0;
+    let mut color_idx: usize = 0;
+    let mut pen_down = true;
+
+    for cmd in commands {
+        match cmd {
+            StitchCommand::Stitch { dx, dy } => {
+                let nx = x + *dx as f32;
+                let ny = y + *dy as f32;
+                if pen_down {
+                    segments.push(StitchSegment {
+                        x0: x,
+                        y0: y,
+                        x1: nx,
+                        y1: ny,
+                        color_index: color_idx,
+                    });
+                }
+                x = nx;
+                y = ny;
+                pen_down = true;
+            }
+            StitchCommand::Jump { dx, dy } => {
+                x += *dx as f32;
+                y += *dy as f32;
+                pen_down = false;
+            }
+            StitchCommand::Trim => {
+                pen_down = false;
+            }
+            StitchCommand::ColorChange => {
+                color_idx += 1;
+                pen_down = false;
+            }
+            StitchCommand::End => break,
+        }
+    }
+
+    if segments.is_empty() {
+        return Err(Error::EmptyDesign);
+    }
+
+    let mut min_x = f32::MAX;
+    let mut max_x = f32::MIN;
+    let mut min_y = f32::MAX;
+    let mut max_y = f32::MIN;
+
+    for seg in &segments {
+        min_x = min_x.min(seg.x0).min(seg.x1);
+        max_x = max_x.max(seg.x0).max(seg.x1);
+        min_y = min_y.min(seg.y0).min(seg.y1);
+        max_y = max_y.max(seg.y0).max(seg.y1);
+    }
+
+    Ok(ResolvedDesign {
+        segments,
+        colors,
+        bounds: BoundingBox {
+            min_x,
+            max_x,
+            min_y,
+            max_y,
+        },
+    })
+}
diff --git a/rustitch/src/types.rs b/rustitch/src/types.rs
new file mode 100644
index 0000000..bb8face
--- /dev/null
+++ b/rustitch/src/types.rs
@@ -0,0 +1,29 @@
+#[derive(Debug, Clone)]
+pub enum StitchCommand {
+    Stitch { dx: i16, dy: i16 },
+    Jump { dx: i16, dy: i16 },
+    Trim,
+    ColorChange,
+    End,
+}
+
+pub struct StitchSegment {
+    pub x0: f32,
+    pub y0: f32,
+    pub x1: f32,
+    pub y1: f32,
+    pub color_index: usize,
+}
+
+pub struct BoundingBox {
+    pub min_x: f32,
+    pub max_x: f32,
+    pub min_y: f32,
+    pub max_y: f32,
+}
+
+pub struct ResolvedDesign {
+    pub segments: Vec<StitchSegment>,
+    pub colors: Vec<(u8, u8, u8)>,
+    pub bounds: BoundingBox,
+}
diff --git a/rustitch/src/vp3.rs b/rustitch/src/vp3.rs
new file mode 100644
index 0000000..902c02a
--- /dev/null
+++ b/rustitch/src/vp3.rs
@@ -0,0 +1,343 @@
+use crate::error::Error;
+use crate::types::{ResolvedDesign, StitchCommand};
+
+/// Parse a VP3 (Pfaff/Viking) file from raw bytes.
+///
+/// VP3 is a hierarchical format:
+///   - File header with "%vsm%" magic (or similar signature)
+///   - Design metadata section
+///   - One or more color sections, each containing:
+///     - Thread color (RGB)
+///     - Stitch data block
+///
+/// Byte order: mixed, but length-prefixed strings and section sizes use big-endian.
+/// Stitch encoding: variable-length (1 byte for small moves, 3 bytes for large).
+pub fn parse(data: &[u8]) -> Result<(Vec<StitchCommand>, Vec<(u8, u8, u8)>), Error> {
+    if data.len() < 20 {
+        return Err(Error::TooShort {
+            expected: 20,
+            actual: data.len(),
+        });
+    }
+
+    let mut reader = Reader::new(data);
+
+    // VP3 files start with a magic/signature section
+    // Skip the initial header to find the design data
+    // The format starts with a variable-length producer string, then design sections
+    skip_vp3_header(&mut reader)?;
+
+    let mut colors = Vec::new();
+    let mut commands = Vec::new();
+
+    // Read color sections
+    let color_section_count = reader.read_u16_be()?;
+
+    for _ in 0..color_section_count {
+        if reader.remaining() < 4 {
+            break;
+        }
+
+        let color = read_color_section(&mut reader, &mut commands)?;
+        colors.push(color);
+    }
+
+    if commands.is_empty() {
+        return Err(Error::NoStitchData);
+    }
+
+    if !matches!(commands.last(), Some(StitchCommand::End)) {
+        commands.push(StitchCommand::End);
+    }
+
+    Ok((commands, colors))
+}
+
+/// Parse a VP3 file and resolve to a renderable design.
+pub fn parse_and_resolve(data: &[u8]) -> Result<ResolvedDesign, Error> {
+    let (commands, colors) = parse(data)?;
+    crate::resolve::resolve(&commands, colors)
+}
+
+fn skip_vp3_header(reader: &mut Reader) -> Result<(), Error> {
+    // Skip magic/producer string at start
+    // VP3 starts with a string like "%vsm%" or similar, followed by metadata
+    // Find the start of actual design data by looking for patterns
+
+    // Read and skip the initial producer/signature string
+    skip_string(reader)?;
+
+    // Skip design metadata: dimensions and other header fields
+    // After the producer string there are typically coordinate fields (i32 BE)
+    // and additional metadata strings
+    if reader.remaining() < 38 {
+        return Err(Error::TooShort {
+            expected: 38,
+            actual: reader.remaining(),
+        });
+    }
+
+    // Skip: design size fields (4x i32 = 16 bytes) + unknown bytes (4) + unknown (4)
+    reader.skip(24)?;
+
+    // Skip design notes/comments strings
+    skip_string(reader)?; // x-offset or notes
+    skip_string(reader)?; // y-offset or notes
+
+    // Skip remaining header fields before color sections
+    // There are typically 6 more bytes of header data
+    if reader.remaining() >= 6 {
+        reader.skip(6)?;
+    }
+
+    // Skip another potential string
+    if reader.remaining() >= 2 {
+        let peek = reader.peek_u16_be();
+        if let Ok(len) = peek {
+            if len < 1000 && (len as usize) + 2 <= reader.remaining() {
+                skip_string(reader)?;
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn read_color_section(
+    reader: &mut Reader,
+    commands: &mut Vec<StitchCommand>,
+) -> Result<(u8, u8, u8), Error> {
+    // Color change between sections (except first)
+    if !commands.is_empty() {
+        commands.push(StitchCommand::ColorChange);
+    }
+
+    // Skip section start marker/offset bytes
+    // Color sections start with coordinate offset data
+    if reader.remaining() < 12 {
+        return Err(Error::TooShort {
+            expected: 12,
+            actual: reader.remaining(),
+        });
+    }
+
+    // Skip section offset/position data (2x i32 = 8 bytes)
+    reader.skip(8)?;
+
+    // Skip thread info string
+    skip_string(reader)?;
+
+    // Read thread color: RGB (3 bytes)
+    if reader.remaining() < 3 {
+        return Err(Error::TooShort {
+            expected: 3,
+            actual: reader.remaining(),
+        });
+    }
+    let r = reader.read_u8()?;
+    let g = reader.read_u8()?;
+    let b = reader.read_u8()?;
+
+    // Skip remaining thread metadata (thread type, weight, catalog info)
+    // Skip to stitch data: look for the stitch count field
+    skip_string(reader)?; // thread catalog number
+    skip_string(reader)?; // thread description
+
+    // Skip thread brand and additional metadata
+    // There's typically some padding/unknown bytes here
+    if reader.remaining() >= 18 {
+        reader.skip(18)?;
+    }
+
+    // Read stitch data
+    let stitch_byte_count = if reader.remaining() >= 4 {
+        reader.read_u32_be()? as usize
+    } else {
+        return Ok((r, g, b));
+    };
+
+    if stitch_byte_count == 0 || stitch_byte_count > reader.remaining() {
+        // Skip what we can
+        return Ok((r, g, b));
+    }
+
+    let stitch_end = reader.pos + stitch_byte_count;
+    decode_vp3_stitches(reader, commands, stitch_end);
+
+    // Ensure we're at the right position after stitch data
+    if reader.pos < stitch_end {
+        reader.pos = stitch_end;
+    }
+
+    Ok((r, g, b))
+}
+
+fn decode_vp3_stitches(reader: &mut Reader, commands: &mut Vec<StitchCommand>, end: usize) {
+    while reader.pos < end && reader.remaining() >= 2 {
+        let b1 = reader.data[reader.pos];
+
+        // Check for 3-byte extended coordinates (high bit set on first byte)
+        if b1 & 0x80 != 0 {
+            if reader.remaining() < 4 {
+                break;
+            }
+            let dx = read_i16_be(reader.data, reader.pos);
+            reader.pos += 2;
+            let dy = read_i16_be(reader.data, reader.pos);
+            reader.pos += 2;
+
+            // Large moves are jumps
+            commands.push(StitchCommand::Jump { dx, dy: -dy });
+        } else {
+            // 1-byte per coordinate
+            let dx = reader.data[reader.pos] as i8 as i16;
+            reader.pos += 1;
+            if reader.pos >= end {
+                break;
+            }
+            let dy = -(reader.data[reader.pos] as i8 as i16);
+            reader.pos += 1;
+
+            if dx == 0 && dy == 0 {
+                // Zero-length stitch can be a trim marker
+                commands.push(StitchCommand::Trim);
+            } else {
+                commands.push(StitchCommand::Stitch { dx, dy });
+            }
+        }
+    }
+}
+
+fn skip_string(reader: &mut Reader) -> Result<(), Error> {
+    if reader.remaining() < 2 {
+        return Err(Error::TooShort {
+            expected: reader.pos + 2,
+            actual: reader.data.len(),
+        });
+    }
+    let len = reader.read_u16_be()? as usize;
+    if len > reader.remaining() {
+        return Err(Error::InvalidHeader(format!(
+            "string length {} exceeds remaining data {}",
+            len,
+            reader.remaining()
+        )));
+    }
+    reader.skip(len)?;
+    Ok(())
+}
+
+fn read_i16_be(data: &[u8], pos: usize) -> i16 {
+    i16::from_be_bytes([data[pos], data[pos + 1]])
+}
+
+struct Reader<'a> {
+    data: &'a [u8],
+    pos: usize,
+}
+
+impl<'a> Reader<'a> {
+    fn new(data: &'a [u8]) -> Self {
+        Self { data, pos: 0 }
+    }
+
+    fn remaining(&self) -> usize {
+        self.data.len().saturating_sub(self.pos)
+    }
+
+    fn read_u8(&mut self) -> Result<u8, Error> {
+        if self.pos >= self.data.len() {
+            return Err(Error::TooShort {
+                expected: self.pos + 1,
+                actual: self.data.len(),
+            });
+        }
+        let v = self.data[self.pos];
+        self.pos += 1;
+        Ok(v)
+    }
+
+    fn read_u16_be(&mut self) -> Result<u16, Error> {
+        if self.pos + 2 > self.data.len() {
+            return Err(Error::TooShort {
+                expected: self.pos + 2,
+                actual: self.data.len(),
+            });
+        }
+        let v = u16::from_be_bytes([self.data[self.pos], self.data[self.pos + 1]]);
+        self.pos += 2;
+        Ok(v)
+    }
+
+    fn peek_u16_be(&self) -> Result<u16, Error> {
+        if self.pos + 2 > self.data.len() {
+            return Err(Error::TooShort {
+                expected: self.pos + 2,
+                actual: self.data.len(),
+            });
+        }
+        Ok(u16::from_be_bytes([
+            self.data[self.pos],
+            self.data[self.pos + 1],
+        ]))
+    }
+
+    fn read_u32_be(&mut self) -> Result<u32, Error> {
+        if self.pos + 4 > self.data.len() {
+            return Err(Error::TooShort {
+                expected: self.pos + 4,
+                actual: self.data.len(),
+            });
+        }
+        let v = u32::from_be_bytes([
+            self.data[self.pos],
+            self.data[self.pos + 1],
+            self.data[self.pos + 2],
+            self.data[self.pos + 3],
+        ]);
+        self.pos += 4;
+        Ok(v)
+    }
+
+    fn skip(&mut self, n: usize) -> Result<(), Error> {
+        if self.pos + n > self.data.len() {
+            return Err(Error::TooShort {
+                expected: self.pos + n,
+                actual: self.data.len(),
+            });
+        }
+        self.pos += n;
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn decode_small_stitch() {
+        let mut commands = Vec::new();
+        // Two small stitches: (10, -20) and (5, -3)
+        let data = [0x0A, 0x14, 0x05, 0x03];
+        let mut reader = Reader::new(&data);
+        decode_vp3_stitches(&mut reader, &mut commands, data.len());
+        assert_eq!(commands.len(), 2);
+        assert!(matches!(
+            commands[0],
+            StitchCommand::Stitch { dx: 10, dy: -20 }
+        ));
+    }
+
+    #[test]
+    fn decode_large_jump() {
+        let mut commands = Vec::new();
+        // Large move: high bit set, 2-byte BE dx and dy
+        // dx = 0x8100 = -32512 as i16, dy = 0x0100 = 256
+        let data = [0x81, 0x00, 0x01, 0x00];
+        let mut reader = Reader::new(&data);
+        decode_vp3_stitches(&mut reader, &mut commands, data.len());
+        assert_eq!(commands.len(), 1);
+        assert!(matches!(commands[0], StitchCommand::Jump { .. }));
+    }
+}