diff --git a/.profile b/.profile
deleted file mode 100644
index f4826ea30..000000000
--- a/.profile
+++ /dev/null
@@ -1 +0,0 @@
-LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/app/.apt/lib/x86_64-linux-gnu:/app/.apt/usr/lib/x86_64-linux-gnu/mesa:/app/.apt/usr/lib/x86_64-linux-gnu/pulseaudio:/app/.apt/usr/lib/x86_64-linux-gnu/openblas-pthread
diff --git a/Aptfile b/Aptfile
index 5e033f136..06c91d4c7 100644
--- a/Aptfile
+++ b/Aptfile
@@ -1,5 +1,5 @@
-ffmpeg
-libopenblas0-pthread
-libpq-dev
-libxdamage1
-libxfixes3
+libidn12
+# for idn-ruby on heroku-24 stack
+
+# use https://github.com/heroku/heroku-buildpack-activestorage-preview
+# in place for ffmpeg and its dependent packages to reduce slag size
diff --git a/Procfile b/Procfile
index d15c835b8..f033fd36c 100644
--- a/Procfile
+++ b/Procfile
@@ -11,4 +11,4 @@ worker: bundle exec sidekiq
 #
 # and let the main app use the separate app:
 #
-# heroku config:set STREAMING_API_BASE_URL=wss://<streaming-app>.herokuapp.com -a <main-app>
+# heroku config:set STREAMING_API_BASE_URL=wss://<streaming-app-random>.herokuapp.com -a <main-app>
diff --git a/app.json b/app.json
index 4f05a64f5..5e5a3dc1e 100644
--- a/app.json
+++ b/app.json
@@ -90,9 +90,15 @@
     }
   },
   "buildpacks": [
+    {
+      "url": "https://github.com/heroku/heroku-buildpack-activestorage-preview"
+    },
     {
       "url": "https://github.com/heroku/heroku-buildpack-apt"
     },
+    {
+      "url": "heroku/nodejs"
+    },
     {
       "url": "heroku/ruby"
     }
@@ -100,5 +106,6 @@
   "scripts": {
     "postdeploy": "bundle exec rails db:migrate && bundle exec rails db:seed"
   },
-  "addons": ["heroku-postgresql", "heroku-redis"]
+  "addons": ["heroku-postgresql", "heroku-redis"],
+  "stack": "heroku-24"
 }