diff --git a/schema.go b/schema.go
index 4a815acfe2a2c0d63318635e253afbf9cb5bf9ec..460620b99085730ea5914e6b274f2aebce964890 100644
--- a/schema.go
+++ b/schema.go
@@ -28,7 +28,7 @@ 	}
 
 	unified := constraints.Unify(config)
 	if unified.Err() != nil {
-		err := unified.Validate(cue.Concrete(true), cue.Final())
+		err := unified.Validate(cue.Concrete(true))
 		var errs []string
 		for _, e := range errors.Errors(err) {
 			errs = append(errs, e.Error())
diff --git a/testdata/array_constraints.cue b/testdata/array_constraints.cue
index cbddedf8ce9845994345a2cafcf5e27de5a0296f..8ffac2cdfa35d4a3e9f1e2739a102808077a6841 100644
--- a/testdata/array_constraints.cue
+++ b/testdata/array_constraints.cue
@@ -1,7 +1,7 @@
-import "time"
+#Duration: string & =~"^([0-9]+(ns|us|µs|ms|s|m|h))+$"
 
 s: [string, string]
 i: [int, int, int]
 b: [bool, bool]
-d: [time.Duration, time.Duration]
+d: [#Duration, #Duration]
 x: [string, string, string]
diff --git a/testdata/bad.cue b/testdata/bad.cue
index 5236ab6a31788d122ccadd20fc6293763f5688d2..fef8a31e53d5914ca81b3baa8c425654d962a138 100644
--- a/testdata/bad.cue
+++ b/testdata/bad.cue
@@ -1,4 +1,4 @@
 s: 1
 i: "1"
 b: 1
-d: "1d"
+d: 1
diff --git a/testdata/constraints.cue b/testdata/constraints.cue
index 87ba7977f1f8b08dd5620e1c0ad9dd20626fecc3..e41e0f82ab0868c9dc125529709b755786844dab 100644
--- a/testdata/constraints.cue
+++ b/testdata/constraints.cue
@@ -1,6 +1,6 @@
-import "time"
+#Duration: string & =~"^([0-9]+(ns|us|µs|ms|s|m|h))+$"
 
 s: string
 i: int
 b: bool
-d: time.Duration
+d: #Duration