diff --git a/migrations/023_fix_task_sequences_cascade.sql b/migrations/023_fix_task_sequences_cascade.sql
new file mode 100644
index 0000000..384365d
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+++ b/migrations/023_fix_task_sequences_cascade.sql
@@ -0,0 +1,109 @@
+-- Migration 023: Add ON UPDATE CASCADE to all projects foreign keys
+-- Allows project key updates (rename) to cascade to all dependent tables
+-- Fixes: CF-518 - task project rename command fails due to FK constraints
+
+-- Fix task_sequences table
+ALTER TABLE task_sequences
+    DROP CONSTRAINT IF EXISTS task_sequences_project_fkey;
+
+ALTER TABLE task_sequences
+    ADD CONSTRAINT task_sequences_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix epic_sequences table
+ALTER TABLE epic_sequences
+    DROP CONSTRAINT IF EXISTS epic_sequences_project_fkey;
+
+ALTER TABLE epic_sequences
+    ADD CONSTRAINT epic_sequences_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix versions table
+ALTER TABLE versions
+    DROP CONSTRAINT IF EXISTS versions_project_fkey;
+
+ALTER TABLE versions
+    ADD CONSTRAINT versions_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix epics table
+ALTER TABLE epics
+    DROP CONSTRAINT IF EXISTS epics_project_fkey;
+
+ALTER TABLE epics
+    ADD CONSTRAINT epics_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix tasks table
+ALTER TABLE tasks
+    DROP CONSTRAINT IF EXISTS tasks_project_fkey;
+
+ALTER TABLE tasks
+    ADD CONSTRAINT tasks_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix project_locks table (from migration 004)
+ALTER TABLE project_locks
+    DROP CONSTRAINT IF EXISTS project_locks_project_fkey;
+
+ALTER TABLE project_locks
+    ADD CONSTRAINT project_locks_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix project_archives table (from migration 009)
+ALTER TABLE project_archives
+    DROP CONSTRAINT IF EXISTS project_archives_project_key_fkey;
+
+ALTER TABLE project_archives
+    ADD CONSTRAINT project_archives_project_key_fkey
+    FOREIGN KEY (project_key) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix sessions table (from migration 010)
+-- Note: sessions.project uses ON DELETE SET NULL, so we use ON UPDATE CASCADE
+ALTER TABLE sessions
+    DROP CONSTRAINT IF EXISTS sessions_project_fkey;
+
+ALTER TABLE sessions
+    ADD CONSTRAINT sessions_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE SET NULL
+    ON UPDATE CASCADE;
+
+-- Fix session_sequences table (from migration 010)
+ALTER TABLE session_sequences
+    DROP CONSTRAINT IF EXISTS session_sequences_project_fkey;
+
+ALTER TABLE session_sequences
+    ADD CONSTRAINT session_sequences_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Fix project_documentation table (from migration 016)
+ALTER TABLE project_documentation
+    DROP CONSTRAINT IF EXISTS project_documentation_project_fkey;
+
+ALTER TABLE project_documentation
+    ADD CONSTRAINT project_documentation_project_fkey
+    FOREIGN KEY (project) REFERENCES projects(key)
+    ON DELETE CASCADE
+    ON UPDATE CASCADE;
+
+-- Record migration
+INSERT INTO schema_migrations (version, applied_at)
+VALUES ('023_fix_task_sequences_cascade', NOW())
+ON CONFLICT DO NOTHING;