diff --git a/Cargo.toml b/Cargo.toml
index 908503bf0..101970af8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,6 +12,7 @@ byteorder = "1"
 smallvec = "1"
 unicode-xid = "0.2"
 async-trait = "0.1"
+serde = { version = "1", features = ["derive"] }
 futures-executor = { version = "0.3", optional = true }
 
 [features]
diff --git a/src/syntax/mod.rs b/src/syntax/mod.rs
index e9725f049..f644f0517 100644
--- a/src/syntax/mod.rs
+++ b/src/syntax/mod.rs
@@ -2,6 +2,7 @@
 
 use std::fmt::{self, Display, Formatter};
 use unicode_xid::UnicodeXID;
+use serde::Serialize;
 
 use crate::func::LayoutFunc;
 use crate::size::{Size, ScaleSize};
@@ -257,7 +258,7 @@ fn expect<E: ExpressionKind>(opt: ParseResult<Option<E>>) -> ParseResult<E> {
     }
 }
 
-#[derive(Debug, Clone, Eq, PartialEq)]
+#[derive(Debug, Clone, Eq, PartialEq, Serialize)]
 pub struct Colorization {
     pub tokens: Vec<Spanned<ColorToken>>,
 }
@@ -277,7 +278,8 @@ impl Colorization {
 }
 
 /// Entities which can be colored by syntax highlighting.
-#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Serialize)]
+#[serde(rename_all = "camelCase")]
 pub enum ColorToken {
     Comment,
     Bracket,
@@ -299,7 +301,7 @@ pub enum ColorToken {
     Invalid,
 }
 
-#[derive(Debug, Clone, Eq, PartialEq)]
+#[derive(Debug, Clone, Eq, PartialEq, Serialize)]
 pub struct ErrorMap {
     pub errors: Vec<Spanned<String>>,
 }
diff --git a/src/syntax/parsing.rs b/src/syntax/parsing.rs
index 71d6b251a..f6d0b629a 100644
--- a/src/syntax/parsing.rs
+++ b/src/syntax/parsing.rs
@@ -104,8 +104,11 @@ impl<'s> Parser<'s> {
         let name = self.parse_func_name()?;
 
         self.skip_whitespace();
-        let args = match self.eat() {
-            Some(Spanned { v: Colon, .. }) => self.parse_func_args(),
+        let args = match self.peek() {
+            Some(Spanned { v: Colon, .. }) => {
+                self.eat();
+                self.parse_func_args()
+            }
             Some(Spanned { v: RightBracket, .. }) => FuncArgs::new(),
             other => {
                 self.expected_at("colon or closing bracket", name.span.end);
@@ -119,8 +122,9 @@ impl<'s> Parser<'s> {
     /// Parses the function name if is the next token. Otherwise, it adds an
     /// error and returns `None`.
     fn parse_func_name(&mut self) -> Option<Spanned<Ident>> {
-        match self.eat() {
+        match self.peek() {
             Some(Spanned { v: ExprIdent(ident), span }) => {
+                self.eat();
                 self.colorization.replace_last(ColorToken::FuncName);
                 return Some(Spanned { v: Ident(ident.to_string()), span });
             }
@@ -280,7 +284,7 @@ impl<'s> Parser<'s> {
             None
         })?;
 
-        Some(FuncCall(parser(header, body, self.ctx).unwrap()))
+        parser(header, body, self.ctx).ok().map(|f| FuncCall(f))
     }
 
     /// Skip all whitespace/comment tokens.
diff --git a/src/syntax/span.rs b/src/syntax/span.rs
index 546b3ad60..df9a3520e 100644
--- a/src/syntax/span.rs
+++ b/src/syntax/span.rs
@@ -1,10 +1,11 @@
 //! Spans map elements to the part of source code they originate from.
 
 use std::fmt::{self, Debug, Display, Formatter};
+use serde::Serialize;
 
 
 /// Annotates a value with the part of the source code it corresponds to.
-#[derive(Copy, Clone, Eq, PartialEq, Hash)]
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Serialize)]
 pub struct Spanned<T> {
     pub v: T,
     pub span: Span,
@@ -45,7 +46,7 @@ impl<T> Debug for Spanned<T> where T: std::fmt::Debug {
 }
 
 /// Describes a slice of source code.
-#[derive(Copy, Clone, Eq, PartialEq, Hash)]
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Serialize)]
 pub struct Span {
     pub start: Position,
     pub end: Position,
@@ -83,7 +84,7 @@ impl Display for Span {
 debug_display!(Span);
 
 /// A line-column position in source code.
-#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Serialize)]
 pub struct Position {
     /// The 0-indexed line (inclusive).
     pub line: usize,
diff --git a/tests/layouter/test.typ b/tests/layouter/test.typ
new file mode 100644
index 000000000..b7fd334d1
--- /dev/null
+++ b/tests/layouter/test.typ
@@ -0,0 +1 @@
+[box][hi]
diff --git a/tests/src/layouter.rs b/tests/src/layouter.rs
index 6d38666b0..fa0c631a1 100644
--- a/tests/src/layouter.rs
+++ b/tests/src/layouter.rs
@@ -107,7 +107,7 @@ fn test(name: &str, src: &str) -> DynResult<()> {
 
     // Render the layout into a PNG.
     Command::new("python")
-        .arg("tests/render.py")
+        .arg("tests/src/render.py")
         .arg(name)
         .spawn()
         .expect("failed to run python renderer");
diff --git a/tests/src/render.py b/tests/src/render.py
index bb27e9732..d445e49cd 100644
--- a/tests/src/render.py
+++ b/tests/src/render.py
@@ -38,7 +38,7 @@ class MultiboxRenderer:
             parts = lines[i + 1].split(' ', 2)
             index = int(parts[0]), int(parts[1])
             path = parts[2]
-            self.fonts[index] = os.path.join(BASE, '../../fonts', path)
+            self.fonts[index] = os.path.join(BASE, '../../../fonts', path)
 
         self.content = lines[font_count + 1:]