diff --git a/docker/Dockerfile b/docker/Dockerfile
index 4fb6857..94d9899 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,19 +1,7 @@
 FROM continuumio/miniconda3:latest
 
 RUN apt-get update && apt-get install -y \
-        build-essential \
-        cmake \
-        ffmpeg \
-        git \
-        libboost-all-dev \
-        libjpeg-dev \
-        libpq-dev \
-        libsdl2-dev swig \
         sudo \
-        unzip \
-        xorg-dev \
-        zip \
-        zlib1g-dev \
     && apt clean \
     && rm -rf /var/lib/apt/lists/*
 
diff --git a/environment.yml b/environment.yml
index bb61905..92affe4 100644
--- a/environment.yml
+++ b/environment.yml
@@ -4,7 +4,6 @@ channels:
   - defaults
 dependencies:
   - box2d-py=2.3  # used only in chapter 18, exercise 8
-  - ftfy=6.1  # used only in chapter 16 by the transformers library
   - graphviz  # used only in chapter 6 for dot files
   - python-graphviz  # used only in chapter 6 for dot files
   - ipython=8.5  # a powerful Python shell
@@ -21,8 +20,6 @@ dependencies:
   - pip  # Python's package-management system
   - py-xgboost=1.6  # used only in chapter 6 for optimized Gradient Boosting
   - pydot=1.4  # used only for in chapter 10 for tf.keras.utils.plot_model()
-  - pyglet=1.5  # used only in chapter 18 to render environments
-  - pyopengl=3.1  # used only in chapter 18 to render environments
   - python=3.10  # your beloved programming language! :)
   - requests=2.28  # used only in chapter 19 for REST API queries
   - scikit-learn=1.1  # machine learning library
@@ -42,6 +39,6 @@ dependencies:
     - tensorflow~=2.10.0  # Deep Learning library
     - transformers~=4.21.3  # Natural Language Processing lib for TF or PyTorch
     - urlextract~=1.6.0  # optionally used in chapter 3, exercise 4
-    - gym[atari,accept-rom-license]~=0.26.1  # used only in chapter 18
+    - gym[classic_control,atari,accept-rom-license]~=0.26.1  # used only in ch18
     - google-cloud-aiplatform~=1.17.0  # used only in chapter 19
     - google-cloud-storage~=2.5.0  # used only in chapter 19
diff --git a/requirements.txt b/requirements.txt
index 7fd1c4f..ee866d7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -57,7 +57,6 @@ gym[Box2D,atari,accept-rom-license]~=0.26.1
 ##### Image manipulation
 Pillow~=9.2.0
 graphviz~=0.20.1
-pyglet~=1.5.26
 
 ##### Google Cloud Platform - used only in chapter 19
 google-cloud-aiplatform~=1.17.0
@@ -82,9 +81,6 @@ numexpr~=2.8.3
 nltk~=3.7
 urlextract~=1.6.0
 
-# Optional: these libraries are only used in chapter 16
-ftfy~=6.1.1
-
 # Optional: tqdm displays nice progress bars, ipywidgets for tqdm's notebook
 #           support
 tqdm~=4.64.1