diff --git a/pyproject.toml b/pyproject.toml
index 4b08f58301..f1e5eea051 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -68,7 +68,8 @@ server = [
     "fastapi>=0.103.1",
     "pyyaml~=6.0",
     "optimade[mongo]",
-    "numpy>=1.20"
+    "numpy>=1.20",
+    "jsonlines=>3.1"
 ]
 
 # Client minded
diff --git a/requirements-server.txt b/requirements-server.txt
index 7ac9463e24..643d0854fb 100644
--- a/requirements-server.txt
+++ b/requirements-server.txt
@@ -1,6 +1,7 @@
 elasticsearch==7.17.7
 elasticsearch-dsl==7.4.0
 fastapi==0.103.1
+jsonlines=>3.1
 mongomock==4.1.2
 numpy>=1.20
 pymongo==4.5.0