diff --git a/requirements.txt b/requirements.txt
index 37a62844..7a80c4be 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -46,8 +46,8 @@ torch==1.8.1     # Strax dependency
 scikit-learn==0.24.1
 scipy==1.6.2
 seaborn==0.11.1
-strax==0.15.1
-straxen==0.18.2
+strax==0.15.0
+straxen==0.18.1
 snakeviz==2.1.0
 sphinx==3.5.4
 tables==3.6.1     # pytables, necessary for pandas hdf5 i/o
@@ -55,6 +55,6 @@ tensorflow==2.4.1 # TF2.4.1 should not bring in additional AVX2 requirements (ht
 tensorflow_probability==0.12.1
 tqdm==4.60.0
 utilix==0.5.3      # dependency for straxen, admix
-wfsim==0.5.1
+wfsim==0.5.0
 xe-admix==0.3.1
 zstd==1.4.8.1     # Strax dependency