diff --git a/.evergreen/config.yml b/.evergreen/config.yml
index 4ffdfca581..3230b827b0 100644
--- a/.evergreen/config.yml
+++ b/.evergreen/config.yml
@@ -2247,19 +2247,6 @@ axes:
         variables:
           MOD_WSGI_VERSION: "4"
 
-  # Install and use the driver's C-extensions?
-  - id: c-extensions
-    display_name: "C Extensions"
-    values:
-      - id: "without-c-extensions"
-        display_name: "Without C Extensions"
-        variables:
-          NO_EXT: "1"
-      - id: "with-c-extensions"
-        display_name: "With C Extensions"
-        variables:
-          NO_EXT: ""
-
   # Run with test commands disabled on server?
   - id: disableTestCommands
     display_name: Disable test commands
@@ -3460,6 +3447,89 @@ buildvariants:
     SSL: ssl
     PYTHON_BINARY: /opt/python/3.12/bin/python3
 
+# No C Ext tests.
+- name: no-c-ext-rhel8-py3.9
+  tasks:
+    - name: .standalone
+  display_name: No C Ext RHEL8 py3.9
+  run_on:
+    - rhel87-small
+  expansions:
+    NO_EXT: "1"
+    PYTHON_BINARY: /opt/python/3.9/bin/python3
+- name: no-c-ext-rhel8-py3.10
+  tasks:
+    - name: .replica_set
+  display_name: No C Ext RHEL8 py3.10
+  run_on:
+    - rhel87-small
+  expansions:
+    NO_EXT: "1"
+    PYTHON_BINARY: /opt/python/3.10/bin/python3
+- name: no-c-ext-rhel8-py3.11
+  tasks:
+    - name: .sharded_cluster
+  display_name: No C Ext RHEL8 py3.11
+  run_on:
+    - rhel87-small
+  expansions:
+    NO_EXT: "1"
+    PYTHON_BINARY: /opt/python/3.11/bin/python3
+- name: no-c-ext-rhel8-py3.12
+  tasks:
+    - name: .standalone
+  display_name: No C Ext RHEL8 py3.12
+  run_on:
+    - rhel87-small
+  expansions:
+    NO_EXT: "1"
+    PYTHON_BINARY: /opt/python/3.12/bin/python3
+- name: no-c-ext-rhel8-py3.13
+  tasks:
+    - name: .replica_set
+  display_name: No C Ext RHEL8 py3.13
+  run_on:
+    - rhel87-small
+  expansions:
+    NO_EXT: "1"
+    PYTHON_BINARY: /opt/python/3.13/bin/python3
+
+# Atlas Data Lake tests.
+- name: atlas-data-lake-rhel8-py3.9-no-c
+  tasks:
+    - name: atlas-data-lake-tests
+  display_name: Atlas Data Lake RHEL8 py3.9 No C
+  run_on:
+    - rhel87-small
+  expansions:
+    NO_EXT: "1"
+    PYTHON_BINARY: /opt/python/3.9/bin/python3
+- name: atlas-data-lake-rhel8-py3.9
+  tasks:
+    - name: atlas-data-lake-tests
+  display_name: Atlas Data Lake RHEL8 py3.9
+  run_on:
+    - rhel87-small
+  expansions:
+    PYTHON_BINARY: /opt/python/3.9/bin/python3
+- name: atlas-data-lake-rhel8-py3.13-no-c
+  tasks:
+    - name: atlas-data-lake-tests
+  display_name: Atlas Data Lake RHEL8 py3.13 No C
+  run_on:
+    - rhel87-small
+  expansions:
+    NO_EXT: "1"
+    PYTHON_BINARY: /opt/python/3.13/bin/python3
+- name: atlas-data-lake-rhel8-py3.13
+  tasks:
+    - name: atlas-data-lake-tests
+  display_name: Atlas Data Lake RHEL8 py3.13
+  run_on:
+    - rhel87-small
+  expansions:
+    PYTHON_BINARY: /opt/python/3.13/bin/python3
+
 - matrix_name: "tests-fips"
   matrix_spec:
     platform:
@@ -3482,32 +3552,6 @@ buildvariants:
   tasks:
     - ".6.0"
 
-- matrix_name: "tests-python-version-rhel8-without-c-extensions"
-  matrix_spec:
-    platform: rhel8
-    python-version: "*"
-    c-extensions: without-c-extensions
-    auth-ssl: noauth-nossl
-    coverage: "*"
-  exclude_spec:
-   # These interpreters are always tested without extensions.
-   - platform: rhel8
-     python-version: ["pypy3.9", "pypy3.10"]
-     c-extensions: "*"
-     auth-ssl: "*"
-     coverage: "*"
-  display_name: "${c-extensions} ${python-version} ${platform} ${auth} ${ssl} ${coverage}"
-  tasks: &all-server-versions
-    - ".rapid"
-    - ".latest"
-    - ".8.0"
-    - ".7.0"
-    - ".6.0"
-    - ".5.0"
-    - ".4.4"
-    - ".4.2"
-    - ".4.0"
-
 - matrix_name: "tests-python-version-supports-openssl-102-test-ssl"
   matrix_spec:
     platform: rhel7
@@ -3596,16 +3640,6 @@ buildvariants:
   tasks:
     - "serverless_task_group"
 
-- matrix_name: "data-lake-spec-tests"
-  matrix_spec:
-    platform: ubuntu-22.04
-    python-version: ["3.9", "3.10"]
-    auth: "auth"
-    c-extensions: "*"
-  display_name: "Atlas Data Lake ${python-version} ${c-extensions}"
-  tasks:
-    - name: atlas-data-lake-tests
-
 # OCSP test matrix.
 - name: ocsp-test-rhel8-v4.4-py3.9
   tasks:
diff --git a/.evergreen/scripts/generate_config.py b/.evergreen/scripts/generate_config.py
index 2d20d2de68..aa5bf18c9e 100644
--- a/.evergreen/scripts/generate_config.py
+++ b/.evergreen/scripts/generate_config.py
@@ -528,10 +528,40 @@ def create_green_framework_variants():
     return variants
 
 
+def generate_no_c_ext_variants():
+    variants = []
+    host = "rhel8"
+    for python, topology in zip_cycle(CPYTHONS, TOPOLOGIES):
+        tasks = [f".{topology}"]
+        expansions = dict()
+        handle_c_ext(C_EXTS[0], expansions)
+        display_name = get_display_name("No C Ext", host, python=python)
+        variant = create_variant(
+            tasks, display_name, host=host, python=python, expansions=expansions
+        )
+        variants.append(variant)
+    return variants
+
+
+def generate_atlas_data_lake_variants():
+    variants = []
+    host = "rhel8"
+    for python, c_ext in product(MIN_MAX_PYTHON, C_EXTS):
+        tasks = ["atlas-data-lake-tests"]
+        expansions = dict()
+        handle_c_ext(c_ext, expansions)
+        display_name = get_display_name("Atlas Data Lake", host, python=python, **expansions)
+        variant = create_variant(
+            tasks, display_name, host=host, python=python, expansions=expansions
+        )
+        variants.append(variant)
+    return variants
+
+
 ##################
 # Generate Config
 ##################
 
-variants = create_green_framework_variants()
+variants = generate_atlas_data_lake_variants()
 # print(len(variants))
 generate_yaml(variants=variants)