tooling overhaul

packages/helpers/omit.ts

@@ -1,13 +1,10 @@
 export function omit<Subject extends object, Key extends PropertyKey>(
-  subject: Subject,
-  keys: Key[],
-  // hack: using a conditional type preserves union types
-): Subject extends any ? Omit<Subject, Key> : never {
-  const result: any = {}
-  for (const key in subject) {
-    if (!keys.includes(key as unknown as Key)) {
-      result[key] = subject[key]
-    }
-  }
-  return result
+	subject: Subject,
+	keys: Key[],
+) {
+	const keySet = new Set<PropertyKey>(keys)
+	return Object.fromEntries(
+		Object.entries(subject).filter(([key]) => !keySet.has(key)),
+		// hack: conditional type preserves unions
+	) as Subject extends unknown ? Omit<Subject, Key> : never
 }