diff --git a/base/Dockerfile b/base/Dockerfile
index 5c545a1..49ac10e 100644
--- a/base/Dockerfile
+++ b/base/Dockerfile
@@ -1,4 +1,4 @@
-# Base image: Debian-12
+# Base image: Debian-12 (slim)
 FROM debian:12-slim
 
 # Update local package index, upgrade packages and install required packages. 
@@ -10,7 +10,7 @@ RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y --no-ins
   netcat-openbsd \
 	&& rm -rf /var/lib/apt/lists/*
       
-# Set Java env
+# Set Java env (currently using Java 17)
 ENV JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64/
 
 # Download Hadoop Keys
@@ -19,9 +19,9 @@ RUN curl -O https://dist.apache.org/repos/dist/release/hadoop/common/KEYS
 # Import keys
 RUN gpg --import KEYS
 
-# Set hadoop version & URL
-ENV HADOOP_VERSION 3.4.1
-ENV HADOOP_URL https://www.apache.org/dist/hadoop/common/hadoop-$HADOOP_VERSION/hadoop-$HADOOP_VERSION.tar.gz
+# Set hadoop version & URL (currently using Hadoop 3.4.1)
+ENV HADOOP_VERSION=3.4.1
+ENV HADOOP_URL=https://www.apache.org/dist/hadoop/common/hadoop-$HADOOP_VERSION/hadoop-$HADOOP_VERSION.tar.gz
 
 # Download hadoop and signature, verify with gpg, extract hadoop-ver.tar.hz into /opt and remove hadoop-ver.tar.gz
 RUN set -x \