diff --git a/src/eval/value.rs b/src/eval/value.rs
index b29d01f32..dda1c3e1e 100644
--- a/src/eval/value.rs
+++ b/src/eval/value.rs
@@ -662,7 +662,7 @@ impl From<AnyValue> for Value {
     }
 }
 
-/// Mark a type as a [`Value`].
+/// Make a type castable from a value.
 ///
 /// Given a type `T`, this implements the following traits:
 /// - [`Type`] for `T`,
@@ -684,7 +684,7 @@ impl From<AnyValue> for Value {
 /// This would allow the type `FontFamily` to be cast from:
 /// - a [`Value::Any`] variant already containing a `FontFamily`,
 /// - a string, producing a named font family.
-macro_rules! value {
+macro_rules! castable {
     ($type:ty:
         $type_name:literal
         $(, $pattern:pat => $out:expr)*
diff --git a/src/exec/state.rs b/src/exec/state.rs
index fa16004ed..6f900b546 100644
--- a/src/exec/state.rs
+++ b/src/exec/state.rs
@@ -216,9 +216,9 @@ impl Default for FamilyList {
         Self {
             list: vec![FontFamily::Serif],
             serif: vec!["eb garamond".into()],
-            sans_serif: vec![/* TODO */],
+            sans_serif: vec!["pt sans".into()],
             monospace: vec!["inconsolata".into()],
-            base: vec!["twitter color emoji".into()],
+            base: vec!["twitter color emoji".into(), "latin modern math".into()],
         }
     }
 }
diff --git a/src/library/align.rs b/src/library/align.rs
index 507bc939e..c0ed0416a 100644
--- a/src/library/align.rs
+++ b/src/library/align.rs
@@ -123,6 +123,6 @@ impl Display for AlignValue {
     }
 }
 
-value! {
+castable! {
     AlignValue: "alignment",
 }
diff --git a/src/library/font.rs b/src/library/font.rs
index 8d76328f2..3f816c6dd 100644
--- a/src/library/font.rs
+++ b/src/library/font.rs
@@ -6,20 +6,20 @@ use super::*;
 /// `font`: Configure the font.
 ///
 /// # Positional parameters
-/// - Font size: optional, of type `linear` relative to current font size.
-/// - Font families: variadic, of type `font-family`.
 /// - Body: optional, of type `template`.
 ///
 /// # Named parameters
+/// - Font size: `size`, of type `linear` relative to current font size.
+/// - Font families: `family`, `font-family`, `string` or `array`.
 /// - Font Style: `style`, of type `font-style`.
 /// - Font Weight: `weight`, of type `font-weight`.
 /// - Font Stretch: `stretch`, of type `relative`, between 0.5 and 2.0.
 /// - Top edge of the font: `top-edge`, of type `vertical-font-metric`.
 /// - Bottom edge of the font: `bottom-edge`, of type `vertical-font-metric`.
 /// - Color the glyphs: `color`, of type `color`.
-/// - Serif family definition: `serif`, of type `font-family-definition`.
-/// - Sans-serif family definition: `sans-serif`, of type `font-family-definition`.
-/// - Monospace family definition: `monospace`, of type `font-family-definition`.
+/// - Serif family definition: `serif`, of type `family-def`.
+/// - Sans-serif family definition: `sans-serif`, of type `family-def`.
+/// - Monospace family definition: `monospace`, of type `family-def`.
 ///
 /// # Return value
 /// A template that configures font properties. The effect is scoped to the body
@@ -31,9 +31,9 @@ use super::*;
 ///   - `sans-serif`
 ///   - `monospace`
 ///   - coerces from `string`
-/// - Type `font-family-definition`
+/// - Type `family-def`
 ///   - coerces from `string`
-///   - coerces from `array`
+///   - coerces from `array` of `string`
 /// - Type `font-style`
 ///   - `normal`
 ///   - `italic`
@@ -49,8 +49,8 @@ use super::*;
 ///   - `baseline`
 ///   - `descender`
 pub fn font(ctx: &mut EvalContext, args: &mut FuncArgs) -> Value {
-    let size = args.eat::<Linear>(ctx);
-    let list = args.all::<FontFamily>(ctx);
+    let list = args.named(ctx, "family");
+    let size = args.named::<Linear>(ctx, "size");
     let style = args.named(ctx, "style");
     let weight = args.named(ctx, "weight");
     let stretch = args.named(ctx, "stretch");
@@ -70,7 +70,7 @@ pub fn font(ctx: &mut EvalContext, args: &mut FuncArgs) -> Value {
             font.size = linear.resolve(font.size);
         }
 
-        if !list.is_empty() {
+        if let Some(FontDef(list)) = &list {
             font.families_mut().list = list.clone();
         }
 
@@ -98,15 +98,15 @@ pub fn font(ctx: &mut EvalContext, args: &mut FuncArgs) -> Value {
             font.fill = Fill::Color(color);
         }
 
-        if let Some(FontFamilies(serif)) = &serif {
+        if let Some(FamilyDef(serif)) = &serif {
             font.families_mut().serif = serif.clone();
         }
 
-        if let Some(FontFamilies(sans_serif)) = &sans_serif {
+        if let Some(FamilyDef(sans_serif)) = &sans_serif {
             font.families_mut().sans_serif = sans_serif.clone();
         }
 
-        if let Some(FontFamilies(monospace)) = &monospace {
+        if let Some(FamilyDef(monospace)) = &monospace {
             font.families_mut().monospace = monospace.clone();
         }
 
@@ -117,12 +117,25 @@ pub fn font(ctx: &mut EvalContext, args: &mut FuncArgs) -> Value {
     })
 }
 
-/// A list of font family names.
-#[derive(Debug, Clone, PartialEq)]
-struct FontFamilies(Vec<String>);
+#[derive(Debug)]
+struct FontDef(Vec<FontFamily>);
 
-value! {
-    FontFamilies: "string or array of strings",
+castable! {
+    FontDef: "font family or array of font families",
+    Value::Str(string) => Self(vec![FontFamily::Named(string.to_lowercase())]),
+    Value::Array(values) => Self(values
+        .into_iter()
+        .filter_map(|v| v.cast().ok())
+        .collect()
+    ),
+    #(family: FontFamily) => Self(vec![family]),
+}
+
+#[derive(Debug)]
+struct FamilyDef(Vec<String>);
+
+castable! {
+    FamilyDef: "string or array of strings",
     Value::Str(string) => Self(vec![string.to_lowercase()]),
     Value::Array(values) => Self(values
         .into_iter()
@@ -132,16 +145,16 @@ value! {
     ),
 }
 
-value! {
+castable! {
     FontFamily: "font family",
     Value::Str(string) => Self::Named(string.to_lowercase())
 }
 
-value! {
+castable! {
     FontStyle: "font style",
 }
 
-value! {
+castable! {
     FontWeight: "font weight",
     Value::Int(number) => {
         let [min, max] = [Self::THIN, Self::BLACK];
@@ -161,7 +174,7 @@ value! {
     },
 }
 
-value! {
+castable! {
     FontStretch: "font stretch",
     Value::Relative(relative) => {
         let [min, max] = [Self::ULTRA_CONDENSED, Self::ULTRA_EXPANDED];
@@ -182,6 +195,6 @@ value! {
     },
 }
 
-value! {
+castable! {
     VerticalFontMetric: "vertical font metric",
 }
diff --git a/src/library/grid.rs b/src/library/grid.rs
index 9efa687ca..c2e765141 100644
--- a/src/library/grid.rs
+++ b/src/library/grid.rs
@@ -70,7 +70,7 @@ pub fn grid(ctx: &mut EvalContext, args: &mut FuncArgs) -> Value {
 /// Defines size of rows and columns in a grid.
 type Tracks = Vec<TrackSizing>;
 
-value! {
+castable! {
     Tracks: "array of `auto`s, linears, and fractionals",
     Value::Int(count) => vec![TrackSizing::Auto; count.max(0) as usize],
     Value::Array(values) => values
@@ -79,7 +79,7 @@ value! {
         .collect(),
 }
 
-value! {
+castable! {
     TrackSizing: "`auto`, linear, or fractional",
     Value::Auto => TrackSizing::Auto,
     Value::Length(v) => TrackSizing::Linear(v.into()),
diff --git a/src/library/mod.rs b/src/library/mod.rs
index 6c7360813..4911e5c86 100644
--- a/src/library/mod.rs
+++ b/src/library/mod.rs
@@ -110,6 +110,6 @@ pub fn new() -> Scope {
     std
 }
 
-value! {
+castable! {
     Dir: "direction"
 }
diff --git a/tests/typ/code/call.typ b/tests/typ/code/call.typ
index 76953580f..5351eb290 100644
--- a/tests/typ/code/call.typ
+++ b/tests/typ/code/call.typ
@@ -24,7 +24,7 @@
 #test(alias(alias), "function")
 
 // Library function `font` returns template.
-#test(type(font(12pt)), "template")
+#test(type(font(size: 12pt)), "template")
 
 ---
 // Callee expressions.
diff --git a/tests/typ/text/bidi.typ b/tests/typ/text/bidi.typ
index 078cb1f98..2e7236ca0 100644
--- a/tests/typ/text/bidi.typ
+++ b/tests/typ/text/bidi.typ
@@ -3,7 +3,7 @@
 ---
 // Test reordering with different top-level paragraph directions.
 #let text = [Text טֶקסט]
-#font("EB Garamond", "Noto Serif Hebrew")
+#font(family: ("EB Garamond", "Noto Serif Hebrew"))
 #lang("he") {text}
 #lang("de") {text}
 
@@ -11,7 +11,7 @@
 // Test that consecutive, embedded  LTR runs stay LTR.
 // Here, we have two runs: "A" and italic "B".
 #let text = [أنت A_B_مطرC]
-#font("EB Garamond", "Noto Sans Arabic")
+#font(family: ("EB Garamond", "Noto Sans Arabic"))
 #lang("ar") {text}
 #lang("de") {text}
 
@@ -19,32 +19,32 @@
 // Test that consecutive, embedded RTL runs stay RTL.
 // Here, we have three runs: "גֶ", bold "שֶׁ", and "ם".
 #let text = [Aגֶ*שֶׁ*םB]
-#font("EB Garamond", "Noto Serif Hebrew")
+#font(family: ("EB Garamond", "Noto Serif Hebrew"))
 #lang("he") {text}
 #lang("de") {text}
 
 ---
 // Test embedding up to level 4 with isolates.
-#font("EB Garamond", "Noto Serif Hebrew", "Twitter Color Emoji")
+#font(family: ("EB Garamond", "Noto Serif Hebrew", "Twitter Color Emoji"))
 #lang(dir: rtl)
 א\u{2066}A\u{2067}Bב\u{2069}?
 
 ---
 // Test hard line break (leads to two paragraphs in unicode-bidi).
-#font("Noto Sans Arabic", "EB Garamond")
+#font(family: ("Noto Sans Arabic", "EB Garamond"))
 #lang("ar")
 Life المطر هو الحياة \
 الحياة تمطر is rain.
 
 ---
 // Test spacing.
-#font("EB Garamond", "Noto Serif Hebrew")
+#font(family: ("EB Garamond", "Noto Serif Hebrew"))
 L #h(1cm) ריווחR \
 Lריווח #h(1cm) R
 
 ---
 // Test inline object.
-#font("Noto Serif Hebrew", "EB Garamond")
+#font(family: ("Noto Serif Hebrew", "EB Garamond"))
 #lang("he")
 קרנפיםRh#image("../../res/rhino.png", height: 11pt)inoחיים
 
diff --git a/tests/typ/text/chinese.typ b/tests/typ/text/chinese.typ
index 0800a2209..3fe790eac 100644
--- a/tests/typ/text/chinese.typ
+++ b/tests/typ/text/chinese.typ
@@ -1,7 +1,7 @@
 // Test chinese text from Wikipedia.
 
 ---
-#font("Noto Serif CJK SC")
+#font(family: "Noto Serif CJK SC")
 
 是美国广播公司电视剧《迷失》第3季的第22和23集，也是全剧的第71集和72集
 由执行制作人戴蒙·林道夫和卡尔顿·库斯编剧，导演则是另一名执行制作人杰克·本德
diff --git a/tests/typ/text/font.typ b/tests/typ/text/font.typ
index 317037e2c..f3a9495bd 100644
--- a/tests/typ/text/font.typ
+++ b/tests/typ/text/font.typ
@@ -2,9 +2,9 @@
 
 ---
 // Set same font size in three different ways.
-#font(22pt)[A]
-#font(200%)[A]
-#font(16.5pt + 50%)[A]
+#font(size: 22pt)[A]
+#font(size: 200%)[A]
+#font(size: 16.5pt + 50%)[A]
 
 // Do nothing.
 #font[Normal]
@@ -19,13 +19,13 @@
 #font(stretch: 50%)[Condensed]
 
 // Set family.
-#font("PT Sans")[Sans serif]
+#font(family: "PT Sans")[Sans serif]
 
 // Emoji.
 Emoji: 🐪, 🌋, 🏞
 
 // Math.
-#font("Latin Modern Math")[
+#font(family: "Latin Modern Math")[
     ∫ 𝛼 + 3𝛽 d𝑡
 ]
 
@@ -49,9 +49,9 @@ Emoji: 🐪, 🌋, 🏞
 ---
 // Test class definitions.
 #font(sans-serif: "PT Sans")
-#font(sans-serif)[Sans-serif.] \
-#font(monospace)[Monospace.] \
-#font(monospace, monospace: ("Nope", "Latin Modern Math"))[Math.]
+#font(family: sans-serif)[Sans-serif.] \
+#font(family: monospace)[Monospace.] \
+#font(family: monospace, monospace: ("Nope", "Latin Modern Math"))[Math.]
 
 ---
 // Ref: false
diff --git a/tests/typ/text/shaping.typ b/tests/typ/text/shaping.typ
index ba543e715..9c6f2966e 100644
--- a/tests/typ/text/shaping.typ
+++ b/tests/typ/text/shaping.typ
@@ -7,11 +7,11 @@
 Le fira
 
 // This should just shape nicely.
-#font("Noto Sans Arabic")
+#font(family: "Noto Sans Arabic")
 دع النص يمطر عليك
 
 // This should form a three-member family.
-#font("Twitter Color Emoji")
+#font(family: "Twitter Color Emoji")
 👩‍👩‍👦 🤚🏿
 
 // These two shouldn't be affected by a zero-width joiner.
@@ -20,7 +20,7 @@ Le fira
 ---
 // Test font fallback.
 
-#font("EB Garamond", "Noto Sans Arabic", "Twitter Color Emoji")
+#font(family: ("EB Garamond", "Noto Sans Arabic", "Twitter Color Emoji"))
 
 // Font fallback for emoji.
 A😀B
@@ -40,6 +40,6 @@ A🐈中文B
 ---
 // Test reshaping.
 
-#font("Noto Serif Hebrew")
+#font(family: "Noto Serif Hebrew")
 #lang("he")
 ס \ טֶ
diff --git a/tests/typ/text/whitespace.typ b/tests/typ/text/whitespace.typ
index 418c3a129..29c3e9906 100644
--- a/tests/typ/text/whitespace.typ
+++ b/tests/typ/text/whitespace.typ
@@ -36,11 +36,11 @@ A #for _ in (none,) {"B"}C
 
 ---
 // Test that a run consisting only of whitespace isn't trimmed.
-A#font("PT Sans")[ ]B
+A#font(family: "PT Sans")[ ]B
 
 ---
 // Test font change after space.
-Left #font("PT Sans")[Right].
+Left #font(family: "PT Sans")[Right].
 
 ---
 // Test that space at start of line is not trimmed.