diff --git a/supabase/migrations/20250121_add_feed_arm_affiliation.sql b/supabase/migrations/20250121_add_feed_arm_affiliation.sql
new file mode 100644
index 00000000..fb962ff1
--- /dev/null
+++ b/supabase/migrations/20250121_add_feed_arm_affiliation.sql
@@ -0,0 +1,39 @@
+-- Add arm_affiliation column to community_posts
+ALTER TABLE public.community_posts
+ADD COLUMN IF NOT EXISTS arm_affiliation TEXT DEFAULT 'labs' NOT NULL;
+
+-- Create index on arm_affiliation for faster filtering
+CREATE INDEX IF NOT EXISTS idx_community_posts_arm_affiliation ON public.community_posts(arm_affiliation);
+
+-- Create user_followed_arms table to track which arms users follow
+CREATE TABLE IF NOT EXISTS public.user_followed_arms (
+  id uuid PRIMARY KEY DEFAULT gen_random_uuid(),
+  user_id uuid NOT NULL REFERENCES public.user_profiles(id) ON DELETE CASCADE,
+  arm_id TEXT NOT NULL,
+  followed_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+  UNIQUE(user_id, arm_id)
+);
+
+-- Create index on user_id for faster lookups
+CREATE INDEX IF NOT EXISTS idx_user_followed_arms_user_id ON public.user_followed_arms(user_id);
+
+-- Create index on arm_id for faster filtering
+CREATE INDEX IF NOT EXISTS idx_user_followed_arms_arm_id ON public.user_followed_arms(arm_id);
+
+-- Enable RLS on user_followed_arms
+ALTER TABLE public.user_followed_arms ENABLE ROW LEVEL SECURITY;
+
+-- Policy: Users can read all followed arms data
+CREATE POLICY "user_followed_arms_read" ON public.user_followed_arms
+  FOR SELECT TO authenticated USING (true);
+
+-- Policy: Users can manage their own followed arms
+CREATE POLICY "user_followed_arms_manage_self" ON public.user_followed_arms
+  FOR ALL TO authenticated USING (user_id = auth.uid()) WITH CHECK (user_id = auth.uid());
+
+-- Update community_posts table constraints and indexes
+CREATE INDEX IF NOT EXISTS idx_community_posts_created_at ON public.community_posts(created_at DESC);
+CREATE INDEX IF NOT EXISTS idx_community_posts_author_id ON public.community_posts(author_id);
+
+-- Add grant for service role (backend API access)
+GRANT SELECT, INSERT, UPDATE, DELETE ON public.user_followed_arms TO service_role;