diff --git a/supabase/migrations/20260305100000_fix_profile_posts_performance.sql b/supabase/migrations/20260305100000_fix_profile_posts_performance.sql
new file mode 100644
index 00000000..5407ba38
--- /dev/null
+++ b/supabase/migrations/20260305100000_fix_profile_posts_performance.sql
@@ -0,0 +1,66 @@
+-- Add missing indexes on document foreign keys used by get_profile_posts
+CREATE INDEX IF NOT EXISTS comments_on_documents_document_idx
+  ON public.comments_on_documents (document);
+
+CREATE INDEX IF NOT EXISTS document_mentions_in_bsky_document_idx
+  ON public.document_mentions_in_bsky (document);
+
+CREATE INDEX IF NOT EXISTS documents_in_publications_document_idx
+  ON public.documents_in_publications (document);
+
+-- Add a stored generated column to extract the DID from at:// URIs
+-- at://did:plc:xxx/collection/rkey -> did:plc:xxx
+ALTER TABLE public.documents
+  ADD COLUMN identity_did text GENERATED ALWAYS AS (split_part(uri, '/', 3)) STORED;
+
+-- Composite index for efficient profile post lookups: filter by DID, order by sort_date
+CREATE INDEX documents_identity_did_sort_idx
+  ON public.documents (identity_did, sort_date DESC, uri DESC);
+
+-- Rewrite get_profile_posts to use the new identity_did column
+CREATE OR REPLACE FUNCTION get_profile_posts(
+  p_did text,
+  p_cursor_sort_date timestamptz DEFAULT NULL,
+  p_cursor_uri text DEFAULT NULL,
+  p_limit int DEFAULT 20
+)
+RETURNS TABLE (
+  uri text,
+  data jsonb,
+  sort_date timestamptz,
+  comments_count bigint,
+  mentions_count bigint,
+  recommends_count bigint,
+  publication_uri text,
+  publication_record jsonb,
+  publication_name text
+)
+LANGUAGE sql STABLE
+AS $$
+  SELECT
+    d.uri,
+    d.data,
+    d.sort_date,
+    (SELECT count(*) FROM comments_on_documents c WHERE c.document = d.uri),
+    (SELECT count(*) FROM document_mentions_in_bsky m WHERE m.document = d.uri),
+    (SELECT count(*) FROM recommends_on_documents r WHERE r.document = d.uri),
+    pub.uri,
+    pub.record,
+    pub.name
+  FROM documents d
+  LEFT JOIN LATERAL (
+    SELECT p.uri, p.record, p.name
+    FROM documents_in_publications dip
+    JOIN publications p ON p.uri = dip.publication
+    WHERE dip.document = d.uri
+    LIMIT 1
+  ) pub ON true
+  WHERE d.identity_did = p_did
+    AND (
+      p_cursor_sort_date IS NULL
+      OR d.sort_date < p_cursor_sort_date
+      OR (d.sort_date = p_cursor_sort_date AND d.uri < p_cursor_uri)
+    )
+  ORDER BY d.sort_date DESC, d.uri DESC
+  LIMIT p_limit;
+$$;