diff --git a/DEVELOPMENT.md b/DEVELOPMENT.md
index ca06764..2078025 100644
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -24,7 +24,7 @@ If any of the above dependencies are not present on your system, the first invoc
 ## How to run the test suite
 
 Prerequisites:
-* Go >= 1.18
+* Go >= 1.20
 
 You can run the test suite by simply doing
 
diff --git a/api/go.mod b/api/go.mod
index bfb8b8a..3be0362 100644
--- a/api/go.mod
+++ b/api/go.mod
@@ -1,6 +1,6 @@
 module github.com/fluxcd/helm-controller/api
 
-go 1.18
+go 1.20
 
 require (
 	github.com/fluxcd/pkg/apis/kustomize v1.1.0
diff --git a/go.mod b/go.mod
index 392915c..b55deb3 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/fluxcd/helm-controller
 
-go 1.18
+go 1.20
 
 replace github.com/fluxcd/helm-controller/api => ./api
 
diff --git a/tests/fuzz/Dockerfile.builder b/tests/fuzz/Dockerfile.builder
index 909571e..1eb6c7a 100644
--- a/tests/fuzz/Dockerfile.builder
+++ b/tests/fuzz/Dockerfile.builder
@@ -1,5 +1,11 @@
 FROM gcr.io/oss-fuzz-base/base-builder-go
 
+RUN wget https://go.dev/dl/go1.20.5.linux-amd64.tar.gz \
+    && mkdir temp-go \
+    && rm -rf /root/.go/* \
+    && tar -C temp-go/ -xzf go1.20.5.linux-amd64.tar.gz \
+    && mv temp-go/go/* /root/.go/
+
 ENV SRC=$GOPATH/src/github.com/fluxcd/helm-controller
 ENV FLUX_CI=true