diff --git a/.devcontainer/Dockerfile b/.devcontainer/Dockerfile
index 118f00b..4e118c2 100644
--- a/.devcontainer/Dockerfile
+++ b/.devcontainer/Dockerfile
@@ -62,7 +62,7 @@ RUN apt-get update \
 	&& rm -rf /var/lib/apt/lists/*
 ENV Z88DK_PATH="/opt/z88dk"
 RUN cpanm -l $HOME/perl5 --no-wget local::lib Template::Plugin::YAML \
-	&& git clone --depth 1 --branch v2.3 --recursive https://github.com/z88dk/z88dk.git ${Z88DK_PATH} \
+	&& git clone --depth 1 --branch v2.4 --recursive https://github.com/z88dk/z88dk.git ${Z88DK_PATH} \
 	&& cd ${Z88DK_PATH} \ 
 	&& eval "$(perl -I$HOME/perl5/lib/perl5 -Mlocal::lib)" \
 	&& chmod 777 build.sh \
diff --git a/.devcontainer/devcontainer.json b/.devcontainer/devcontainer.json
index 49d71d1..db76a5b 100644
--- a/.devcontainer/devcontainer.json
+++ b/.devcontainer/devcontainer.json
@@ -2,7 +2,7 @@
 	"name": "ZX Spectrum dev tools",
 	//"build": { "dockerfile": "Dockerfile" },
 	// The Dockerfile takes an age to build due to z88dk, so pull from prebuilt:
-	"image": "boarstone.mcphail.uk/mcphail/speccydev:v1.2",
+	"image": "boarstone.mcphail.uk/mcphail/speccydev:v2.0",
 	"remoteUser": "ubuntu",
 	"runArgs": [
 		"--network=host"
diff --git a/README.md b/README.md
index 56207b1..f55a9d6 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# Development tools for the ZX Spectrum v1.2
+# Development tools for the ZX Spectrum v2.0
 
 The Dockerfile is the basis of the devcontainer and can be changed to add or remove tools. It will take a long time to build locally, so by default the devcontainer will pull a prebuilt version. Edit `.devcontainer/devcontainer.json` if you would rather build your own.
 
@@ -8,7 +8,7 @@ The devcontainer contains:
 - z80asm version 1.8 (assembler)
 - z80dasm version 1.1.6 (disassembler)
 - zmakebas version 1.2b (creates BASIC programs)
-- z88dk version 2.3 (C compiler and other utilities including assembler)
+- z88dk version 2.4 (C compiler and other utilities including assembler)
 - utilities from the FUSE emulator version 1.4.3:
     - audio2tape
     - createhdf
@@ -60,6 +60,10 @@ Several useful VSCode extentsions will be installed, including a Z80 assembly la
 
 Thanks to the many authors of these wonderful tools and extensions; to think what we could have made with these in 1985!
 
+## Breaking changes from v1.x
+
+The newest release of z88dk has been included. This brings substantial improvements over v2.3, but I cannot guarantee it will compile your code in the same way. If this causes problems, please use an older version of the devcontainer.
+
 ## Install
 
 This devcontainer should work in Windows, Linux and MacOS. It is recommended to install: