diff --git a/README.tlm b/README.tlm
index f36e60c..285bb06 100644
--- a/README.tlm
+++ b/README.tlm
@@ -10,9 +10,9 @@ Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam blandit dolor nibh,
 #(https://krzak.org)
 ^ Links with no alt text
 
-$[https://krzak.org/krzak-icon.png]
-$(https://krzak.org/krzak-icon.png)
 $[https://krzak.org/krzak-icon.png|img]
+$[https://frokfrdk.com/projects/staircase/staircase.wav]
+$(https://9front.org/movies/no.mp4)
 
 *italic*
 **bold**
diff --git a/src/html.odin b/src/html.odin
index 301ed96..c791386 100644
--- a/src/html.odin
+++ b/src/html.odin
@@ -3,6 +3,25 @@ package main
 import "core:fmt"
 import "core:strings"
 
+escape_html :: proc(s: string, allocator := context.temp_allocator) -> string {
+	b := strings.builder_make(allocator)
+	for ch in s {
+		switch ch {
+		case '&':
+			strings.write_string(&b, "&")
+		case '<':
+			strings.write_string(&b, "&lt;")
+		case '>':
+			strings.write_string(&b, "&gt;")
+		case '"':
+			strings.write_string(&b, "&quot;")
+		case:
+			strings.write_rune(&b, ch)
+		}
+	}
+	return strings.to_string(b)
+}
+
 get_text_content :: proc(token: ^Token, b: ^strings.Builder) {
 	if token.type == .Text {
 		if v, ok := token.value.(string); ok {
@@ -237,12 +256,12 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.FootnoteRef:
 		if id, ok := token.value.(string); ok {
-			fmt.printf("<a href=\"#fn-%s\" id=\"ref-%s\"><sup>%s</sup></a>", id, id, id)
+			fmt.printf("<a href=\"#fn-%s\" id=\"ref-%s\"><sup>%s</sup></a>", escape_html(id), escape_html(id), escape_html(id))
 		}
 
 	case TokenType.FootnoteDef:
 		if id, ok := token.value.(string); ok {
-			fmt.printf("<div class=\"footnote\" id=\"fn-%s\"><a href=\"#ref-%s\">^</a> ", id, id)
+			fmt.printf("<div class=\"footnote\" id=\"fn-%s\"><a href=\"#ref-%s\">^</a> ", escape_html(id), escape_html(id))
 			for child in token.children {
 				print_html(child)
 			}
@@ -269,7 +288,7 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.InlineCode:
 		if code, ok := token.value.(string); ok {
-			fmt.printf("<code>%s</code>", code)
+			fmt.printf("<code>%s</code>", escape_html(code))
 		}
 
 	case TokenType.HorizontalRule:
@@ -298,8 +317,8 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.HeaderLink:
 		if target, ok := token.value.(string); ok {
-			slug := slugifyifyifyify(target)
-			fmt.printf("<a href=\"#%s\">", slug)
+		slug := slugifyifyifyify(target)
+		fmt.printf("<a href=\"#%s\">", escape_html(slug))
 			for child in token.children {
 				print_html(child)
 			}
@@ -308,7 +327,7 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.Link:
 		if url, ok := token.value.(string); ok {
-			fmt.printf("<a href=\"%s\">", url)
+			fmt.printf("<a href=\"%s\">", escape_html(url))
 			for child in token.children {
 				print_html(child)
 			}
@@ -322,12 +341,12 @@ print_html :: proc(token: ^Token) {
 				get_text_content(child, &b)
 			}
 			alt_text := strings.to_string(b)
-			fmt.printf("<img src=\"%s\" alt=\"%s\">", url, alt_text)
+			fmt.printf("<img src=\"%s\" alt=\"%s\">", escape_html(url), escape_html(alt_text))
 		}
 
 	case TokenType.Audio:
 		if url, ok := token.value.(string); ok {
-			fmt.printf("<audio controls src=\"%s\">", url)
+			fmt.printf("<audio controls src=\"%s\">", escape_html(url))
 			for child in token.children {
 				print_html(child)
 			}
@@ -336,7 +355,7 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.Video:
 		if url, ok := token.value.(string); ok {
-			fmt.printf("<video controls src=\"%s\">", url)
+			fmt.printf("<video controls src=\"%s\">", escape_html(url))
 			for child in token.children {
 				print_html(child)
 			}
@@ -345,12 +364,12 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.Iframe:
 		if url, ok := token.value.(string); ok {
-			fmt.printf("<iframe src=\"%s\"></iframe>", url)
+			fmt.printf("<iframe src=\"%s\"></iframe>", escape_html(url))
 		}
 
 	case TokenType.Script:
 		if url, ok := token.value.(string); ok {
-			fmt.printf("<script src=\"%s\"></script>", url)
+			fmt.printf("<script src=\"%s\"></script>", escape_html(url))
 		}
 
 	case TokenType.ScriptBlock:
@@ -360,7 +379,7 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.Variable:
 		if name, ok := token.value.(string); ok {
-			fmt.printf("<span data-tlm-var=\"%s\">", name)
+			fmt.printf("<span data-tlm-var=\"%s\">", escape_html(name))
 			for child in token.children {
 				print_html(child)
 			}
@@ -376,8 +395,8 @@ print_html :: proc(token: ^Token) {
 			val := strings.to_string(b)
 			fmt.printf(
 				"<template data-tlm-def=\"%s\" data-tlm-value=\"%s\"></template>",
-				name,
-				val,
+				escape_html(name),
+				escape_html(val),
 			)
 		}
 
@@ -386,7 +405,7 @@ print_html :: proc(token: ^Token) {
 
 	case TokenType.Text:
 		if v, ok := token.value.(string); ok {
-			fmt.print(v)
+			fmt.print(escape_html(v))
 		}
 		for child in token.children {
 			print_html(child)