diff --git a/README.md b/README.md
index 8baca2a..a444d97 100644
--- a/README.md
+++ b/README.md
@@ -42,5 +42,5 @@ Build
 -----
 
 Run `make mobileinsight.sif` or `make mobileinsight-spark.sif` to build the
-apptainer image. The spark version includes both `mobileinsight` along with
-`pyspark`.
+corresponding apptainer image. The spark version includes both `mobileinsight`
+along with `pyspark` for distributed log processing.
diff --git a/mobileinsight.def b/mobileinsight.def
index 4b0d801..84b3263 100644
--- a/mobileinsight.def
+++ b/mobileinsight.def
@@ -19,6 +19,7 @@ From: ubuntu:22.04
             git \
             python3 \
             python3-pip \
+            python3-venv \
             python3-wxgtk4.0 \
             python3-matplotlib \
             cmake \