diff --git a/backend/migrations/0005_problem_embedding.surql b/backend/migrations/0005_problem_embedding.surql
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+-- TarninaHub — migration 0005: problem embeddings for semantic matchmaking
+-- Idempotent, additive. Mirrors the innovation vector index.
+
+DEFINE FIELD IF NOT EXISTS embedding ON TABLE problem TYPE option<array<float>>;
+DEFINE INDEX IF NOT EXISTS problem_embedding ON TABLE problem FIELDS embedding
+  HNSW DIMENSION 1536 DIST COSINE TYPE F32;