diff --git a/README.md b/README.md
index 67b9974ce..81353717b 100644
--- a/README.md
+++ b/README.md
@@ -266,7 +266,7 @@ You can try it out by running some sample code: `c3c.exe compile ../resources/ex
 
 1. Make sure you have a C compiler that handles C11 and a C++ compiler, such as GCC or Clang. Git also needs to be installed.
 2. Install CMake: `sudo apt install cmake`
-3. Install LLVM 15 (or greater: C3C supports LLVM 13-16): `sudo apt-get install clang-15 zlib1g zlib1g-dev libllvm15 llvm-15 llvm-15-dev llvm-15-runtime liblld-15-dev liblld-15`
+3. Install LLVM 15 (or greater: C3C supports LLVM 15-17): `sudo apt-get install clang-15 zlib1g zlib1g-dev libllvm15 llvm-15 llvm-15-dev llvm-15-runtime liblld-15-dev liblld-15`
 4. Clone the C3C github repository: `git clone https://github.com/c3lang/c3c.git`
 5. Enter the C3C directory `cd c3c`.
 6. Create a build directory `mkdir build`
diff --git a/build-with-docker.sh b/build-with-docker.sh
index 6ea8ab065..51e6f5ee6 100755
--- a/build-with-docker.sh
+++ b/build-with-docker.sh
@@ -2,12 +2,12 @@
 ## build-with-docker.sh
 ## @author gdm85
 ##
-## Script to build c3c for either Ubuntu 21 or 22.
+## Script to build c3c for either Ubuntu 22 or 23.
 ##
 #
 
 if [ $# -ne 1 -a $# -ne 2 ]; then
-	echo "Usage: build-with-docker.sh (21|22) [Debug|Release]" 1>&2
+	echo "Usage: build-with-docker.sh (22|23) [Debug|Release]" 1>&2
 	exit 1
 fi
 
@@ -29,17 +29,14 @@ else
 fi
 
 TAG="$1"
-if [ "$1" = 21 ]; then
-	UBUNTU_VERSION="21.10"
-	LLVM_VERSION="13"
-elif [ "$1" = 22 ]; then
-	UBUNTU_VERSION="22.04"
-	LLVM_VERSION="14"
-elif [ "$1" = 22 ]; then
+if [ "$1" = 22 ]; then
+	UBUNTU_VERSION="22.10"
+	LLVM_VERSION="15"
+elif [ "$1" = 23 ]; then
 	UBUNTU_VERSION="23.04"
 	LLVM_VERSION="15"
 else
-	echo "ERROR: expected 21, 22 or 23 as Ubuntu version argument" 1>&2
+	echo "ERROR: expected 22 or 23 as Ubuntu version argument" 1>&2
 	exit 2
 fi
 IMAGE="$IMAGE:$TAG"