diff --git a/alembic/versions/004_add_memory_tables.py b/alembic/versions/004_add_memory_tables.py
index 7a062cb..ebd2ae1 100644
--- a/alembic/versions/004_add_memory_tables.py
+++ b/alembic/versions/004_add_memory_tables.py
@@ -19,6 +19,7 @@ from typing import Sequence, Union
 
 import sqlalchemy as sa
 from alembic import op
+from sqlalchemy.dialects import postgresql
 
 revision: str = "004"
 down_revision: Union[str, None] = "003"
@@ -39,13 +40,12 @@ def upgrade() -> None:
     # ── memory_core ───────────────────────────────────────────────────────────
     op.create_table(
         "memory_core",
-        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column("id", postgresql.UUID(as_uuid=False), primary_key=True),
         sa.Column(
             "user_id",
-            sa.String(36),
+            postgresql.UUID(as_uuid=False),
             sa.ForeignKey("users.id", ondelete="CASCADE"),
             nullable=False,
-            index=True,
         ),
         sa.Column("key", sa.String(255), nullable=False),
         sa.Column("value_encrypted", sa.Text, nullable=False),
@@ -62,10 +62,10 @@ def upgrade() -> None:
     # The embedding column uses pgvector's vector(1536) type.
     op.create_table(
         "memory_associative",
-        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column("id", postgresql.UUID(as_uuid=False), primary_key=True),
         sa.Column(
             "user_id",
-            sa.String(36),
+            postgresql.UUID(as_uuid=False),
             sa.ForeignKey("users.id", ondelete="CASCADE"),
             nullable=False,
         ),
@@ -93,10 +93,10 @@ def upgrade() -> None:
     # ── memory_episodic ───────────────────────────────────────────────────────
     op.create_table(
         "memory_episodic",
-        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column("id", postgresql.UUID(as_uuid=False), primary_key=True),
         sa.Column(
             "user_id",
-            sa.String(36),
+            postgresql.UUID(as_uuid=False),
             sa.ForeignKey("users.id", ondelete="CASCADE"),
             nullable=False,
         ),
@@ -115,10 +115,10 @@ def upgrade() -> None:
     # ── memory_proactive ──────────────────────────────────────────────────────
     op.create_table(
         "memory_proactive",
-        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column("id", postgresql.UUID(as_uuid=False), primary_key=True),
         sa.Column(
             "user_id",
-            sa.String(36),
+            postgresql.UUID(as_uuid=False),
             sa.ForeignKey("users.id", ondelete="CASCADE"),
             nullable=False,
         ),
diff --git a/docker-compose.yml b/docker-compose.yml
index 07b33c6..c54bd25 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -17,7 +17,7 @@ services:
     restart: unless-stopped
 
   db:
-    image: postgres:16-alpine
+    image: pgvector/pgvector:pg16
     environment:
       POSTGRES_USER: postgres
       POSTGRES_PASSWORD: postgres