diff --git a/src/convert.rs b/src/convert.rs
new file mode 100644
index 0000000..0a211e6
--- /dev/null
+++ b/src/convert.rs
@@ -0,0 +1,146 @@
+#[derive(Debug, Clone, PartialEq)]
+enum S {
+	None,
+	P,
+	Code,
+}
+
+pub fn convert_document(markdown: &str) -> String {
+	let mut html = String::new();
+	let mut state = S::None;
+
+	for line in markdown.lines() {
+		if line.starts_with("```") {
+			if state == S::Code {
+				html += "</pre>\n";
+				state = S::None;
+				continue;
+			}
+			if state == S::P {
+				html += "</p>\n";
+			}
+			state = S::Code;
+			html += "<pre>\n";
+			continue;
+		}
+
+		if state == S::Code {
+			html += line;
+			html += "\n";
+			continue;
+		}
+
+		if let Some((start, header)) = line.split_once(' ') {
+			let level = start.len();
+			if (1..=6).contains(&level) && start.chars().all(|c| c == '#') {
+				if state == S::P {
+					state = S::None;
+					html += "</p>\n";
+				}
+				let header = &convert_line(header);
+				html += &format!("<h{level}>{header}</h{level}>\n");
+				continue;
+			}
+		}
+
+		if state == S::P && line.is_empty() {
+			state = S::None;
+			html += "</p>\n";
+		} else if !line.is_empty() {
+			if state == S::None {
+				state = S::P;
+				html += "<p>\n";
+			}
+			html += &convert_line(line);
+			html += "<br>\n";
+		}
+	}
+	html
+}
+
+fn convert_line(source: &str) -> String {
+	let mut out = String::new();
+	let mut is_em = false;
+	let mut is_b = false;
+	let mut is_code = false;
+	let mut is_ul = false;
+	let toggle = |state: bool, tag: &str| {
+		if state {
+			format!("<{tag}>")
+		} else {
+			format!("</{tag}>")
+		}
+	};
+
+	let mut link: Option<(String, Option<String>)> = None;
+
+	let mut chars = source.chars().peekable();
+	while let Some(c) = chars.next() {
+		if let Some(link_c) = &mut link {
+			match link_c {
+				(link_text, None) => {
+					if c == ']' {
+						if chars.peek() == Some(&'(') {
+							_ = chars.next();
+							link_c.1 = Some(String::new());
+						} else {
+							out += &format!("[{link_text}]");
+							link = None;
+						}
+					} else {
+						link_text.push(c);
+					}
+				}
+				(link_text, Some(href)) => {
+					if c == ')' {
+						out += &format!("<a href=\"{href}\">{link_text}</a>");
+						link = None;
+					} else {
+						href.push(c);
+					}
+				}
+			}
+			continue;
+		}
+		if c == '[' {
+			link = Some((String::new(), None));
+		} else if c == '*' {
+			if chars.peek() == Some(&'*') {
+				_ = chars.next();
+				is_b = !is_b;
+				out += &toggle(is_b, "strong");
+			} else {
+				is_em = !is_em;
+				out += &toggle(is_em, "em");
+			}
+		} else if c == '`' {
+			is_code = !is_code;
+			out += &toggle(is_code, "code");
+		} else if c == '_' {
+			is_ul = !is_ul;
+			out += &toggle(is_ul, "u");
+		} else {
+			out.push(c);
+		}
+	}
+	if let Some((link_text, href)) = link {
+		out += &format!("[{link_text}");
+		if let Some(href) = href {
+			out += &format!("]({href}");
+		}
+	}
+
+	if is_em {
+		out += "</em>";
+	}
+	if is_b {
+		out += "</strong>";
+	}
+	if is_code {
+		out += "</code>";
+	}
+	if is_ul {
+		out += "</u>";
+	}
+	out
+}
diff --git a/src/main.rs b/src/main.rs
index 8681195..13add86 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -6,6 +6,9 @@ use std::{
 	path::{Path, PathBuf},
 };
 
+mod convert;
+use convert::convert_document;
+
 const SRC_DIR: &str = "write";
 const OUT_DIR: &str = "site";
 const CONTENT_MARKER: &str = "CONTENT HERE";
@@ -53,67 +56,12 @@ fn build_file(path: &Path) -> Result {
 	}
 }
 
-#[derive(Debug, Clone, PartialEq)]
-enum S {
-	None,
-	P,
-	Code,
-}
-
 fn convert_file(path: &Path) -> Result {
-	let markdown = read_to_string(path)?;
 	let out_path = PathBuf::from(OUT_DIR).join(path.strip_prefix(SRC_DIR)?);
 	let out_path = out_path.with_extension("html");
 
-	let mut html = String::new();
-	let mut state = S::None;
-
-	for line in markdown.lines() {
-		if line.starts_with("```") {
-			if state == S::Code {
-				html += "</pre>\n";
-				state = S::None;
-				continue;
-			}
-			if state == S::P {
-				html += "</p>\n";
-			}
-			state = S::Code;
-			html += "<pre>\n";
-			continue;
-		}
-
-		if state == S::Code {
-			html += line;
-			html += "\n";
-			continue;
-		}
-
-		if let Some((start, header)) = line.split_once(' ') {
-			let level = start.len();
-			if (1..=6).contains(&level) && start.chars().all(|c| c == '#') {
-				if state == S::P {
-					state = S::None;
-					html += "</p>\n";
-				}
-				let header = &convert_line(header);
-				html += &format!("<h{level}>{header}</h{level}>\n");
-				continue;
-			}
-		}
-
-		if state == S::P && line.is_empty() {
-			state = S::None;
-			html += "</p>\n";
-		} else if !line.is_empty() {
-			if state == S::None {
-				state = S::P;
-				html += "<p>\n";
-			}
-			html += &convert_line(line);
-			html += "<br>\n";
-		}
-	}
+	let markdown = read_to_string(path)?;
+	let html = convert_document(&markdown);
 
 	let template = read_to_string(TEMPLATE_FILE)?;
 	let html = template.replacen(CONTENT_MARKER, &html, 1);
@@ -126,90 +74,3 @@ fn convert_file(path: &Path) -> Result {
 	println!("built {}", out_path.display());
 	Ok(())
 }
-
-fn convert_line(source: &str) -> String {
-	let mut out = String::new();
-	let mut is_em = false;
-	let mut is_b = false;
-	let mut is_code = false;
-	let mut is_ul = false;
-	let toggle = |state: bool, tag: &str| {
-		if state {
-			format!("<{tag}>")
-		} else {
-			format!("</{tag}>")
-		}
-	};
-
-	let mut link: Option<(String, Option<String>)> = None;
-
-	let mut chars = source.chars().peekable();
-	while let Some(c) = chars.next() {
-		if let Some(link_c) = &mut link {
-			match link_c {
-				(link_text, None) => {
-					if c == ']' {
-						if chars.peek() == Some(&'(') {
-							_ = chars.next();
-							link_c.1 = Some(String::new());
-						} else {
-							out += &format!("[{link_text}]");
-							link = None;
-						}
-					} else {
-						link_text.push(c);
-					}
-				}
-				(link_text, Some(href)) => {
-					if c == ')' {
-						out += &format!("<a href=\"{href}\">{link_text}</a>");
-						link = None;
-					} else {
-						href.push(c);
-					}
-				}
-			}
-			continue;
-		}
-		if c == '[' {
-			link = Some((String::new(), None));
-		} else if c == '*' {
-			if chars.peek() == Some(&'*') {
-				_ = chars.next();
-				is_b = !is_b;
-				out += &toggle(is_b, "strong");
-			} else {
-				is_em = !is_em;
-				out += &toggle(is_em, "em");
-			}
-		} else if c == '`' {
-			is_code = !is_code;
-			out += &toggle(is_code, "code");
-		} else if c == '_' {
-			is_ul = !is_ul;
-			out += &toggle(is_ul, "u");
-		} else {
-			out.push(c);
-		}
-	}
-	if let Some((link_text, href)) = link {
-		out += &format!("[{link_text}");
-		if let Some(href) = href {
-			out += &format!("]({href}");
-		}
-	}
-
-	if is_em {
-		out += &toggle(false, "em");
-	}
-	if is_b {
-		out += &toggle(false, "b");
-	}
-	if is_code {
-		out += &toggle(false, "code");
-	}
-	if is_ul {
-		out += &toggle(false, "u");
-	}
-	out
-}