diff --git a/owntracks/ot-recorder/Dockerfile b/owntracks/ot-recorder/Dockerfile
index a94c298..bc01233 100644
--- a/owntracks/ot-recorder/Dockerfile
+++ b/owntracks/ot-recorder/Dockerfile
@@ -2,24 +2,24 @@
 # Dockerfile for ot-recorder
 #
 
-FROM debian:buster
+FROM debian:bullseye
 MAINTAINER EasyPi Software Foundation
 
 RUN set -xe \
     && apt-get update \
     && apt-get install -y curl gnupg \
     && curl -sSL http://repo.owntracks.org/repo.owntracks.org.gpg.key | apt-key add - \
-    && echo 'deb http://repo.owntracks.org/debian buster main' > /etc/apt/sources.list.d/owntracks.list \
+    && echo 'deb http://repo.owntracks.org/debian bullseye main' > /etc/apt/sources.list.d/owntracks.list \
     && apt-get update \
     && apt-get install -y ot-recorder || true \
     && rm -rf /var/lib/apt/lists/*
 
-ENV OTR_HOST       mqtt.eclipse.org
-ENV OTR_PORT       1883
-ENV OTR_HTTPHOST   0.0.0.0
-ENV OTR_HTTPPORT   8083
-ENV OTR_TOPICS     owntracks/#
-ENV OTR_STORAGEDIR /var/spool/owntracks/recorder/store
+ENV OTR_HOST=mqtt.eclipse.org \
+    OTR_PORT=1883             \
+    OTR_HTTPHOST=0.0.0.0      \
+    OTR_HTTPPORT=8083         \
+    OTR_TOPICS=owntracks/#    \
+    OTR_STORAGEDIR=/var/spool/owntracks/recorder/store
 
 VOLUME $OTR_STORAGEDIR