diff --git a/fendermint/testing/materializer/manifests/root-only.yaml b/fendermint/testing/materializer/manifests/root-only.yaml
new file mode 100644
index 000000000..811919428
--- /dev/null
+++ b/fendermint/testing/materializer/manifests/root-only.yaml
@@ -0,0 +1,25 @@
+accounts:
+  alice: {}
+  bob: {}
+  charlie: {}
+rootnet:
+  type: New
+  validators:
+    alice: '100'
+  balances:
+    alice: '1000000000000000000'
+    bob: '2000000000000000000'
+    charlie: '3000000000000000000'
+  nodes:
+    node-1:
+      mode:
+        type: Validator
+        validator: alice
+      ethapi: true
+
+    node-2:
+      mode:
+        type: Full
+      ethapi: false
+      seed_nodes:
+        - node-1
diff --git a/fendermint/testing/materializer/src/manifest.rs b/fendermint/testing/materializer/src/manifest.rs
index b8a6e9005..e74863a31 100644
--- a/fendermint/testing/materializer/src/manifest.rs
+++ b/fendermint/testing/materializer/src/manifest.rs
@@ -39,6 +39,7 @@ pub struct Manifest {
     pub rootnet: Rootnet,
 
     /// Subnets created on the rootnet.
+    #[serde(default, skip_serializing_if = "BTreeMap::is_empty")]
     pub subnets: SubnetMap,
 }
 
@@ -131,6 +132,7 @@ pub struct Subnet {
     /// Child subnets under this parent.
     ///
     /// The subnet ID exists so we can find the outcome of existing deployments in the log.
+    #[serde(default, skip_serializing_if = "BTreeMap::is_empty")]
     pub subnets: SubnetMap,
 }
 
@@ -141,9 +143,11 @@ pub struct Node {
     /// Indicate whether to run the Ethereum API.
     pub ethapi: bool,
     /// The nodes from which CometBFT should bootstrap itself.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
     pub seed_nodes: Vec<NodeId>,
     /// The parent node that the top-down syncer follows;
     /// or leave it empty if node is on the rootnet.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
     pub parent_node: Option<ParentNode>,
 }
 
diff --git a/fendermint/testing/materializer/tests/docker.rs b/fendermint/testing/materializer/tests/docker.rs
new file mode 100644
index 000000000..606528bfc
--- /dev/null
+++ b/fendermint/testing/materializer/tests/docker.rs
@@ -0,0 +1,22 @@
+// Copyright 2022-2024 Protocol Labs
+// SPDX-License-Identifier: Apache-2.0, MIT
+
+use fendermint_testing_materializer::{
+    docker::DockerMaterializer,
+    manifest::{self, Manifest},
+};
+
+mod manifests {
+    use fendermint_testing_materializer::manifest::Manifest;
+
+    pub const ROOT_ONLY: &str = include_str!("../manifests/root-only.yaml");
+
+    pub fn parse_yaml(yaml: &str) -> Manifest {
+        serde_yaml::from_str(yaml).expect("failed to parse manifest")
+    }
+}
+
+#[tokio::test]
+async fn test_root_only() {
+    let _manifest = manifests::parse_yaml(manifests::ROOT_ONLY);
+}