diff --git a/.editorconfig b/.editorconfig
old mode 100755
new mode 100644
diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
old mode 100755
new mode 100644
diff --git a/.github/FUNDING.yml b/.github/FUNDING.yml
old mode 100755
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diff --git a/.github/ISSUE_TEMPLATE/config.yml b/.github/ISSUE_TEMPLATE/config.yml
old mode 100755
new mode 100644
diff --git a/.github/ISSUE_TEMPLATE/issue.bug.yml b/.github/ISSUE_TEMPLATE/issue.bug.yml
old mode 100755
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diff --git a/.github/ISSUE_TEMPLATE/issue.feature.yml b/.github/ISSUE_TEMPLATE/issue.feature.yml
old mode 100755
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diff --git a/.github/workflows/call_issue_pr_tracker.yml b/.github/workflows/call_issue_pr_tracker.yml
old mode 100755
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diff --git a/.github/workflows/call_issues_cron.yml b/.github/workflows/call_issues_cron.yml
old mode 100755
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diff --git a/.github/workflows/external_trigger.yml b/.github/workflows/external_trigger.yml
old mode 100755
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diff --git a/.github/workflows/external_trigger_scheduler.yml b/.github/workflows/external_trigger_scheduler.yml
old mode 100755
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diff --git a/.github/workflows/greetings.yml b/.github/workflows/greetings.yml
old mode 100755
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diff --git a/.github/workflows/package_trigger_scheduler.yml b/.github/workflows/package_trigger_scheduler.yml
old mode 100755
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diff --git a/Dockerfile b/Dockerfile
index b58f75d..1e3993f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 
-FROM ghcr.io/linuxserver/baseimage-alpine:3.20
+FROM ghcr.io/linuxserver/baseimage-alpine:3.21
 
 # set version label
 ARG BUILD_DATE
@@ -75,7 +75,7 @@ RUN \
   pip install -U --no-cache-dir \
     pip \
     wheel && \
-  pip install -U --no-cache-dir --find-links https://wheel-index.linuxserver.io/alpine-3.20/ \
+  pip install -U --no-cache-dir --find-links https://wheel-index.linuxserver.io/alpine-3.21/ \
     beautifulsoup4 \
     beets==${BEETS_VERSION} \
     beets-extrafiles \
diff --git a/Dockerfile.aarch64 b/Dockerfile.aarch64
index e3cf89a..8ea6829 100644
--- a/Dockerfile.aarch64
+++ b/Dockerfile.aarch64
@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 
-FROM ghcr.io/linuxserver/baseimage-alpine:arm64v8-3.20
+FROM ghcr.io/linuxserver/baseimage-alpine:arm64v8-3.21
 
 # set version label
 ARG BUILD_DATE
@@ -76,7 +76,7 @@ RUN \
   pip install -U --no-cache-dir \
     pip \
     wheel && \
-  pip install -U --no-cache-dir --find-links https://wheel-index.linuxserver.io/alpine-3.20/ \
+  pip install -U --no-cache-dir --find-links https://wheel-index.linuxserver.io/alpine-3.21/ \
     beautifulsoup4 \
     beets==${BEETS_VERSION} \
     beets-extrafiles \
diff --git a/LICENSE b/LICENSE
old mode 100755
new mode 100644
diff --git a/README.md b/README.md
index 53ddbeb..dc51c5d 100644
--- a/README.md
+++ b/README.md
@@ -78,6 +78,14 @@ See [Beets](http://beets.io/) for more info.
 
 Contains [beets-extrafiles](https://github.com/Holzhaus/beets-extrafiles) plugin, [configuration details](https://github.com/Holzhaus/beets-extrafiles#usage)
 
+## Read-Only Operation
+
+This image can be run with a read-only container filesystem. For details please [read the docs](https://docs.linuxserver.io/misc/read-only/).
+
+## Non-Root Operation
+
+This image can be run with a non-root user. For details please [read the docs](https://docs.linuxserver.io/misc/non-root/).
+
 ## Usage
 
 To help you get started creating a container from this image you can either use docker-compose or the docker cli.
@@ -135,6 +143,8 @@ Containers are configured using parameters passed at runtime (such as those abov
 | `-v /config` | Persistent config files |
 | `-v /music` | Music library |
 | `-v /downloads` | Non processed music |
+| `--read-only=true` | Run container with a read-only filesystem. Please [read the docs](https://docs.linuxserver.io/misc/read-only/). |
+| `--user=1000:1000` | Run container with a non-root user. Please [read the docs](https://docs.linuxserver.io/misc/non-root/). |
 
 ## Environment variables from files (Docker secrets)
 
@@ -298,6 +308,7 @@ Once registered you can define the dockerfile to use with `-f Dockerfile.aarch64
 
 ## Versions
 
+* **27.01.25:** - Rebase to Alpine 3.21.
 * **01.10.24:** - Add packages required for Discogs plugin.
 * **28.08.24:** - Rebase to Alpine 3.20, switch from Pillow to Imagemagick.
 * **23.12.23:** - Rebase to Alpine 3.19.
diff --git a/readme-vars.yml b/readme-vars.yml
index c7172ac..f6d221c 100644
--- a/readme-vars.yml
+++ b/readme-vars.yml
@@ -27,6 +27,8 @@ param_volumes:
 param_usage_include_ports: true
 param_ports:
   - {external_port: "8337", internal_port: "8337", port_desc: "Application WebUI"}
+readonly_supported: true
+nonroot_supported: true
 # application setup block
 app_setup_block_enabled: true
 app_setup_block: |
@@ -83,6 +85,7 @@ init_diagram: |
   "beets:latest" <- Base Images
 # changelog
 changelogs:
+  - {date: "27.01.25:", desc: "Rebase to Alpine 3.21."}
   - {date: "01.10.24:", desc: "Add packages required for Discogs plugin."}
   - {date: "28.08.24:", desc: "Rebase to Alpine 3.20, switch from Pillow to Imagemagick."}
   - {date: "23.12.23:", desc: "Rebase to Alpine 3.19."}
diff --git a/root/etc/s6-overlay/s6-rc.d/init-beets-config/run b/root/etc/s6-overlay/s6-rc.d/init-beets-config/run
index 3ae5607..61a2b3a 100755
--- a/root/etc/s6-overlay/s6-rc.d/init-beets-config/run
+++ b/root/etc/s6-overlay/s6-rc.d/init-beets-config/run
@@ -7,6 +7,8 @@ cp -n /defaults/config.yaml /config/config.yaml
 
 chmod +x /config/beets.sh
 
-# permissions
-lsiown -R abc:abc \
-    /config
+if [[ -z ${LSIO_NON_ROOT_USER} ]]; then
+    # permissions
+    lsiown -R abc:abc \
+        /config
+fi
diff --git a/root/etc/s6-overlay/s6-rc.d/svc-beets/run b/root/etc/s6-overlay/s6-rc.d/svc-beets/run
index 4c74a20..13c6cb3 100755
--- a/root/etc/s6-overlay/s6-rc.d/svc-beets/run
+++ b/root/etc/s6-overlay/s6-rc.d/svc-beets/run
@@ -1,6 +1,12 @@
 #!/usr/bin/with-contenv bash
 # shellcheck shell=bash
 
-exec \
-    s6-notifyoncheck -d -n 300 -w 1000 -c "nc -z localhost 8337" \
-    s6-setuidgid abc beet web
+if [[ -z ${LSIO_NON_ROOT_USER} ]]; then
+    exec \
+        s6-notifyoncheck -d -n 300 -w 1000 -c "nc -z localhost 8337" \
+            s6-setuidgid abc beet web
+else
+    exec \
+        s6-notifyoncheck -d -n 300 -w 1000 -c "nc -z localhost 8337" \
+            beet web
+fi