diff --git a/Docker/sslip.io-dns-server/Dockerfile b/Docker/sslip.io-dns-server/Dockerfile
index 1a92c4c..430deab 100644
--- a/Docker/sslip.io-dns-server/Dockerfile
+++ b/Docker/sslip.io-dns-server/Dockerfile
@@ -26,7 +26,7 @@ LABEL org.opencontainers.image.authors="Brian Cunnie <brian.cunnie@gmail.com>"
 RUN dnf install -y bind-utils
 
 ARG TARGETARCH # amd64, arm64 (so I can run on AWS graviton2)
-RUN curl -f -L https://github.com/cunnie/sslip.io/releases/download/4.2.0/sslip.io-dns-server-linux-$TARGETARCH \
+RUN curl -f -L https://github.com/cunnie/sslip.io/releases/download/4.2.1/sslip.io-dns-server-linux-$TARGETARCH \
   -o /usr/sbin/sslip.io-dns-server; \
   chmod 755 /usr/sbin/sslip.io-dns-server
 
diff --git a/bin/make_all b/bin/make_all
index 309cd8a..a159fc1 100755
--- a/bin/make_all
+++ b/bin/make_all
@@ -4,7 +4,7 @@
 #
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 cd $DIR/..
-ldflags="-X xip/xip.VersionSemantic=4.2.0 \
+ldflags="-X xip/xip.VersionSemantic=4.2.1 \
          -X xip/xip.VersionDate=$(date +%Y/%m/%d-%H:%M:%S%z) \
          -X xip/xip.VersionGitHash=$(git rev-parse --short HEAD)"
 export GOOS GOARCH
diff --git a/docs/DEVELOPER.md b/docs/DEVELOPER.md
index 5760a88..f9025a7 100644
--- a/docs/DEVELOPER.md
+++ b/docs/DEVELOPER.md
@@ -4,8 +4,8 @@ These instructions are meant primarily for me when deploying a new release;
 they might not make sense unless you're on my workstation.
 
 ```bash
-export OLD_VERSION=4.1.1
-export VERSION=4.2.0
+export OLD_VERSION=4.2.0
+export VERSION=4.2.1
 cd ~/workspace/sslip.io
 git pull -r --autostash
 # update the version number for the TXT record for version.status.sslip.io
@@ -41,7 +41,7 @@ Test from another window:
 
 ```bash
 export DNS_SERVER_IP=127.0.0.1
-export VERSION=4.2.0
+export VERSION=4.2.1
 # quick sanity test
 ( dig +short 127.0.0.1.example.com @$DNS_SERVER_IP
 echo 127.0.0.1 ) | uniq -c
@@ -78,7 +78,7 @@ Review the output then close the second window. Stop the server in the
 original window. Commit our changes:
 
 ```bash
-GIT_MESSAGE="$VERSION: -ptr-domain flag sets PTR domain, which now defaults to nip.io"
+GIT_MESSAGE="$VERSION: blocklist is moved to separate repo"
 git add -p
 git ci -vm"$GIT_MESSAGE"
 git tag $VERSION
diff --git a/spec/check-dns_spec.rb b/spec/check-dns_spec.rb
index b3d977a..d569f61 100644
--- a/spec/check-dns_spec.rb
+++ b/spec/check-dns_spec.rb
@@ -20,7 +20,7 @@ end
 
 domains_env = ENV['DOMAINS'] || 'example.com'
 domains = domains_env.split(',').map(&:strip)
-sslip_version = '4.2.0'
+sslip_version = '4.2.1'
 
 domains.each do |domain|
   whois_nameservers = get_whois_nameservers(domain)