diff --git a/TODO b/TODO
index 179b290..c42ab8f 100644
--- a/TODO
+++ b/TODO
@@ -7,7 +7,6 @@
 
 # auxiliary columns
 
-- enforce column types, ie STRICT?
 - in xBestIndex, ensure there are no constraints on any aux column
 - DELETE and UPDATE support
 - later:
diff --git a/sqlite-vec.c b/sqlite-vec.c
index 172a270..1acf4d2 100644
--- a/sqlite-vec.c
+++ b/sqlite-vec.c
@@ -2074,7 +2074,7 @@ int vec0_parse_auxiliary_column_definition(const char *source, int source_length
                  0 ||
              sqlite3_strnicmp(token.start, "double",
                               token.end - token.start) == 0) {
-    column_type = SQLITE_INTEGER;
+    column_type = SQLITE_FLOAT;
   } else if (sqlite3_strnicmp(token.start, "blob", token.end - token.start) ==0) {
     column_type = SQLITE_BLOB;
   } else {
@@ -6736,6 +6736,20 @@ int vec0Update_Insert(sqlite3_vtab *pVTab, int argc, sqlite3_value **argv,
       }
       int auxiliary_key_idx = p->user_column_idxs[i];
       sqlite3_value * v = argv[2+VEC0_COLUMN_USERN_START + i];
+      int v_type = sqlite3_value_type(v);
+      if(v_type != SQLITE_NULL && (v_type != p->auxiliary_columns[auxiliary_key_idx].type)) {
+        sqlite3_finalize(stmt);
+        rc = SQLITE_ERROR;
+        vtab_set_error(
+        pVTab,
+        "Auxiliary column type mismatch: The auxiliary column %.*s has type %s, but %s was provided.",
+        p->auxiliary_columns[auxiliary_key_idx].name_length,
+        p->auxiliary_columns[auxiliary_key_idx].name,
+        type_name(p->auxiliary_columns[auxiliary_key_idx].type),
+        type_name(v_type)
+      );
+        goto cleanup;
+      }
       sqlite3_bind_value(stmt, 1 + auxiliary_key_idx, v);
     }
 
diff --git a/tests/__snapshots__/test-auxiliary.ambr b/tests/__snapshots__/test-auxiliary.ambr
index e706f6a..8cba12a 100644
--- a/tests/__snapshots__/test-auxiliary.ambr
+++ b/tests/__snapshots__/test-auxiliary.ambr
@@ -161,3 +161,86 @@
     ]),
   })
 # ---
+# name: test_types
+  OrderedDict({
+    'sql': 'select * from v',
+    'rows': list([
+    ]),
+  })
+# ---
+# name: test_types.1
+  OrderedDict({
+    'sql': 'insert into v(vector, aux_int, aux_float, aux_text, aux_blob) values (?, ?, ?, ?, ?)',
+    'rows': list([
+    ]),
+  })
+# ---
+# name: test_types.2
+  OrderedDict({
+    'sql': 'select * from v',
+    'rows': list([
+      OrderedDict({
+        'rowid': 1,
+        'vector': b'\x11\x11\x11\x11',
+        'aux_int': 1,
+        'aux_float': 1.22,
+        'aux_text': 'text',
+        'aux_blob': b'blob',
+      }),
+    ]),
+  })
+# ---
+# name: test_types.3
+  dict({
+    'error': 'OperationalError',
+    'message': 'Auxiliary column type mismatch: The auxiliary column aux_int has type INTEGER, but TEXT was provided.',
+  })
+# ---
+# name: test_types.4
+  dict({
+    'error': 'OperationalError',
+    'message': 'Auxiliary column type mismatch: The auxiliary column aux_float has type FLOAT, but TEXT was provided.',
+  })
+# ---
+# name: test_types.5
+  dict({
+    'error': 'OperationalError',
+    'message': 'Auxiliary column type mismatch: The auxiliary column aux_text has type TEXT, but INTEGER was provided.',
+  })
+# ---
+# name: test_types.6
+  dict({
+    'error': 'OperationalError',
+    'message': 'Auxiliary column type mismatch: The auxiliary column aux_blob has type BLOB, but INTEGER was provided.',
+  })
+# ---
+# name: test_types.7
+  OrderedDict({
+    'sql': 'insert into v(vector, aux_int, aux_float, aux_text, aux_blob) values (?, ?, ?, ?, ?)',
+    'rows': list([
+    ]),
+  })
+# ---
+# name: test_types.8
+  OrderedDict({
+    'sql': 'select * from v',
+    'rows': list([
+      OrderedDict({
+        'rowid': 1,
+        'vector': b'\x11\x11\x11\x11',
+        'aux_int': 1,
+        'aux_float': 1.22,
+        'aux_text': 'text',
+        'aux_blob': b'blob',
+      }),
+      OrderedDict({
+        'rowid': 2,
+        'vector': b'\x11\x11\x11\x11',
+        'aux_int': None,
+        'aux_float': None,
+        'aux_text': None,
+        'aux_blob': None,
+      }),
+    ]),
+  })
+# ---
diff --git a/tests/test-auxiliary.py b/tests/test-auxiliary.py
index 8e210a0..f09de96 100644
--- a/tests/test-auxiliary.py
+++ b/tests/test-auxiliary.py
@@ -36,7 +36,40 @@ def test_normal(db, snapshot):
 
 
 def test_types(db, snapshot):
-    pass
+    db.execute(
+        """
+          create virtual table v using vec0(
+            vector float[1],
+            +aux_int integer,
+            +aux_float float,
+            +aux_text text,
+            +aux_blob blob
+          )
+        """
+    )
+    assert exec(db, "select * from v") == snapshot()
+    INSERT = "insert into v(vector, aux_int, aux_float, aux_text, aux_blob) values (?, ?, ?, ?, ?)"
+
+    assert (
+        exec(db, INSERT, [b"\x11\x11\x11\x11", 1, 1.22, "text", b"blob"]) == snapshot()
+    )
+    assert exec(db, "select * from v") == snapshot()
+
+    # bad types
+    assert (
+        exec(db, INSERT, [b"\x11\x11\x11\x11", "not int", 1.2, "text", b"blob"])
+        == snapshot()
+    )
+    assert (
+        exec(db, INSERT, [b"\x11\x11\x11\x11", 1, "not float", "text", b"blob"])
+        == snapshot()
+    )
+    assert exec(db, INSERT, [b"\x11\x11\x11\x11", 1, 1.2, 1, b"blob"]) == snapshot()
+    assert exec(db, INSERT, [b"\x11\x11\x11\x11", 1, 1.2, "text", 1]) == snapshot()
+
+    # NULLs are totally chill
+    assert exec(db, INSERT, [b"\x11\x11\x11\x11", None, None, None, None]) == snapshot()
+    assert exec(db, "select * from v") == snapshot()
 
 
 def test_updates(db, snapshot):