diff --git a/src/wasm/ast_node.rs b/src/wasm/ast_node.rs
index 218e8e3c..76b7f35b 100644
--- a/src/wasm/ast_node.rs
+++ b/src/wasm/ast_node.rs
@@ -63,6 +63,7 @@ use super::WasmStandardProperties;
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct WasmAstNodeWrapper<I> {
+    #[serde(rename = "ast-node")]
     pub(crate) ast_node: String,
     #[serde(rename = "standard-properties")]
     pub(crate) standard_properties: WasmStandardProperties,
diff --git a/src/wasm/standard_properties.rs b/src/wasm/standard_properties.rs
index c6bf0214..de46b165 100644
--- a/src/wasm/standard_properties.rs
+++ b/src/wasm/standard_properties.rs
@@ -10,8 +10,11 @@ use crate::types::StandardProperties;
 pub(crate) struct WasmStandardProperties {
     pub(crate) begin: usize,
     pub(crate) end: usize,
+    #[serde(rename = "contents-begin")]
     pub(crate) contents_begin: Option<usize>,
+    #[serde(rename = "contents-end")]
     pub(crate) contents_end: Option<usize>,
+    #[serde(rename = "post-blank")]
     pub(crate) post_blank: PostBlank,
 }
 
diff --git a/src/wasm_test/compare.rs b/src/wasm_test/compare.rs
index 59bd9110..b0c32d47 100644
--- a/src/wasm_test/compare.rs
+++ b/src/wasm_test/compare.rs
@@ -87,7 +87,7 @@ fn compare_json_value<'b, 's>(
     emacs: &'b Token<'s>,
 ) -> Result<WasmDiffResult<'s>, Box<dyn std::error::Error>> {
     match (value, emacs) {
-        (serde_json::Value::Object(wasm), Token::List(el)) if wasm.contains_key("ast_node") => {
+        (serde_json::Value::Object(wasm), Token::List(el)) if wasm.contains_key("ast-node") => {
             // We hit a regular ast node.
             compare_ast_node(source, el, wasm)
         }
@@ -139,7 +139,7 @@ fn compare_ast_node<'b, 's, 'p>(
             .ok_or("Should have a name as the first child.")?
             .as_atom()?;
         let wasm_name = wasm
-            .get("ast_node")
+            .get("ast-node")
             .ok_or("Should have a ast node type.")?
             .as_str()
             .ok_or("Ast node type should be a string.")?;
@@ -248,9 +248,9 @@ fn compare_ast_node<'b, 's, 'p>(
         for (emacs_value, wasm_name) in [
             (emacs_standard_properties.begin, "begin"),
             (emacs_standard_properties.end, "end"),
-            (emacs_standard_properties.contents_begin, "contents_begin"),
-            (emacs_standard_properties.contents_end, "contents_end"),
-            (emacs_standard_properties.post_blank, "post_blank"),
+            (emacs_standard_properties.contents_begin, "contents-begin"),
+            (emacs_standard_properties.contents_end, "contents-end"),
+            (emacs_standard_properties.post_blank, "post-blank"),
         ] {
             match (emacs_value, wasm_standard_properties.get(wasm_name)) {
                 (None, None) => {}