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diff --git a/crates/typst-library/src/loading/yaml.rs b/crates/typst-library/src/loading/yaml.rs
new file mode 100644
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+++ b/crates/typst-library/src/loading/yaml.rs
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+use ecow::{eco_format, EcoString};
+use typst_syntax::Spanned;
+
+use crate::diag::{At, SourceResult};
+use crate::engine::Engine;
+use crate::foundations::{func, scope, Str, Value};
+use crate::loading::Readable;
+use crate::World;
+
+/// Reads structured data from a YAML file.
+///
+/// The file must contain a valid YAML object or array. YAML mappings will be
+/// converted into Typst dictionaries, and YAML sequences will be converted into
+/// Typst arrays. Strings and booleans will be converted into the Typst
+/// equivalents, null-values (`null`, `~` or empty ``) will be converted into
+/// `{none}`, and numbers will be converted to floats or integers depending on
+/// whether they are whole numbers. Custom YAML tags are ignored, though the
+/// loaded value will still be present.
+///
+/// Be aware that integers larger than 2<sup>63</sup>-1 will be converted to
+/// floating point numbers, which may give an approximative value.
+///
+/// The YAML files in the example contain objects with authors as keys,
+/// each with a sequence of their own submapping with the keys
+/// "title" and "published"
+///
+/// # Example
+/// ```example
+/// #let bookshelf(contents) = {
+///   for (author, works) in contents {
+///     author
+///     for work in works [
+///       - #work.title (#work.published)
+///     ]
+///   }
+/// }
+///
+/// #bookshelf(
+///   yaml("scifi-authors.yaml")
+/// )
+/// ```
+#[func(scope, title = "YAML")]
+pub fn yaml(
+    /// The engine.
+    engine: &mut Engine,
+    /// Path to a YAML file.
+    ///
+    /// For more details, see the [Paths section]($syntax/#paths).
+    path: Spanned<EcoString>,
+) -> SourceResult<Value> {
+    let Spanned { v: path, span } = path;
+    let id = span.resolve_path(&path).at(span)?;
+    let data = engine.world.file(id).at(span)?;
+    yaml::decode(Spanned::new(Readable::Bytes(data), span))
+}
+
+#[scope]
+impl yaml {
+    /// Reads structured data from a YAML string/bytes.
+    #[func(title = "Decode YAML")]
+    pub fn decode(
+        /// YAML data.
+        data: Spanned<Readable>,
+    ) -> SourceResult<Value> {
+        let Spanned { v: data, span } = data;
+        serde_yaml::from_slice(data.as_slice())
+            .map_err(|err| eco_format!("failed to parse YAML ({err})"))
+            .at(span)
+    }
+
+    /// Encode structured data into a YAML string.
+    #[func(title = "Encode YAML")]
+    pub fn encode(
+        /// Value to be encoded.
+        value: Spanned<Value>,
+    ) -> SourceResult<Str> {
+        let Spanned { v: value, span } = value;
+        serde_yaml::to_string(&value)
+            .map(|v| v.into())
+            .map_err(|err| eco_format!("failed to encode value as YAML ({err})"))
+            .at(span)
+    }
+}