diff --git a/ci/environment.yml b/ci/environment.yml
index 05e00cbfa9..55b82c68c3 100644
--- a/ci/environment.yml
+++ b/ci/environment.yml
@@ -4,19 +4,19 @@ channels:
   - defaults
 dependencies:
   - llvmdev=11.1.0
+  - toml=0.10.2
+  - pytest=7.2.0
+  - jupyter=1.0.0
   - xeus=5.1.0
   - xeus-zmq=3.0.0
+  - nlohmann_json=3.11.3
+  - jupyter_kernel_test=0.4.4
   - xonsh=0.13.3
-  - rapidjson
-  - nlohmann_json
-  - toml
-  - pytest
-  - jupyter
-  - jupyter_kernel_test
-  - re2c
-  - numpy
+  - re2c=2.2
+  - numpy=1.23.4
   - zlib
   - zstd
-  - ninja
+  - ninja=1.11.0
+  - rapidjson=1.1.0
 #  - bison=3.4  [not win]
 #  - m2-bison=3.4  [win]