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diff --git a/src/hitomezashi.rs b/src/hitomezashi.rs
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+++ b/src/hitomezashi.rs
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+/*
+	hitomezashi-rs  Generates classical colored Hitomezashi stitch patterns
+	Copyright (C) 2024  Nicholas Johnson
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+use rand::Rng;
+
+const TRANSPARENT_SQUARE: char = ' ';
+const OPAQUE_SQUARE: char = '█';
+
+fn print_square(is_transparent: bool) {
+	print!("{}", if is_transparent { TRANSPARENT_SQUARE } else { OPAQUE_SQUARE });
+}
+
+pub fn hitomezashi(width: usize, height: usize, skew: Option<f32>) {
+	let skew: f64 = match skew {
+		Some(n) => { n.into() }
+		None => { 0.5 }
+	};
+
+	let mut rng = rand::thread_rng();
+
+    let init_bit: bool = rng.gen::<bool>();
+	let mut row_bits: Vec<bool> = Vec::with_capacity(height - 1);
+	let mut col_bits: Vec<bool> = Vec::with_capacity(width - 1);
+
+	for _ in 0..(height - 1) {
+		row_bits.push(rng.gen_bool(skew));
+	}
+
+	for _ in 0..(width - 1) {
+		col_bits.push(rng.gen_bool(skew));
+	}
+
+	// each new row of the pattern depends on the bits directly above it
+	let mut above_bits: Vec<bool> = Vec::with_capacity(width);
+
+	above_bits.push(init_bit);
+	print_square(above_bits[0]);
+
+	for col in 1..width {
+	/* each square in the first row is derived from the square to its left. the column bits
+	 * represent whether there's a stitch between the two squares. if there's a stitch, the squares
+	 * are different, otherwise they are the same. */
+		above_bits.push(above_bits[col - 1] ^ col_bits[col - 1]);
+		print_square(above_bits[col]);
+	}
+
+	println!();
+
+	// height-1 because the first row has already been printed
+	for row in 0..(height - 1) {
+		for col in 0..width {
+			/* each square in each successive row is derived from the square above it. the row bits
+			 * represent whether there's a stitch between the two squares. if there's a stitch, the
+			 * squares are different, otherwise they are the same. */
+			above_bits[col] = above_bits[col] ^ (row_bits[row] ^ (col % 2 == 1));
+			print_square(above_bits[col]);
+		}
+		println!();
+	}
+}