diff --git a/snowchains_core/CHANGELOG.md b/snowchains_core/CHANGELOG.md
index 8b6574f8..51590ad3 100644
--- a/snowchains_core/CHANGELOG.md
+++ b/snowchains_core/CHANGELOG.md
@@ -5,6 +5,7 @@
 ### Fixed
 
 - Added a workaround for large process input/output.
+- Followed [dtolnay/serde-yaml@ef9907](https://github.com/dtolnay/serde-yaml/commit/ef990758a19d4d845cf19a8943e7d905909cafd8).
 
 ## [0.8.1] - 2021-01-21Z
 
diff --git a/snowchains_core/src/testsuite.rs b/snowchains_core/src/testsuite.rs
index af6b2f13..9d1921b1 100644
--- a/snowchains_core/src/testsuite.rs
+++ b/snowchains_core/src/testsuite.rs
@@ -101,8 +101,7 @@ impl TestSuite {
         fn key_value(key: impl Serialize, value: impl Serialize) -> serde_yaml::Result<String> {
             let key = serde_yaml::to_value(key)?;
             let mut acc = serde_yaml::to_string(&hashmap!(key => value))?;
-            debug_assert!(acc.starts_with("---\n"));
-            acc += "\n";
+            debug_assert!(acc.starts_with("---\n") && acc.ends_with('\n'));
             Ok(acc.split_off(4))
         }
 
@@ -123,6 +122,7 @@ impl TestSuite {
                 let mut acc = serde_yaml::to_string(&hashmap!(&key => serde_yaml::Value::Null))
                     .ok()?
                     .trim_start_matches("---\n")
+                    .trim_end_matches('\n')
                     .trim_end_matches('~')
                     .to_owned();