diff --git a/cmd/bolt/bench.go b/cmd/bolt/bench.go
index b275542..91af960 100644
--- a/cmd/bolt/bench.go
+++ b/cmd/bolt/bench.go
@@ -283,7 +283,7 @@ func benchStartProfiling(options *BenchOptions) {
 	if options.CPUProfile != "" {
 		cpuprofile, err = os.Create(options.CPUProfile)
 		if err != nil {
-			fatal("bench: could not create cpu profile %q: %v", options.CPUProfile, err)
+			fatalf("bench: could not create cpu profile %q: %v", options.CPUProfile, err)
 		}
 		pprof.StartCPUProfile(cpuprofile)
 	}
@@ -292,7 +292,7 @@ func benchStartProfiling(options *BenchOptions) {
 	if options.MemProfile != "" {
 		memprofile, err = os.Create(options.MemProfile)
 		if err != nil {
-			fatal("bench: could not create memory profile %q: %v", options.MemProfile, err)
+			fatalf("bench: could not create memory profile %q: %v", options.MemProfile, err)
 		}
 		runtime.MemProfileRate = 4096
 	}
@@ -301,7 +301,7 @@ func benchStartProfiling(options *BenchOptions) {
 	if options.BlockProfile != "" {
 		blockprofile, err = os.Create(options.BlockProfile)
 		if err != nil {
-			fatal("bench: could not create block profile %q: %v", options.BlockProfile, err)
+			fatalf("bench: could not create block profile %q: %v", options.BlockProfile, err)
 		}
 		runtime.SetBlockProfileRate(1)
 	}
diff --git a/cmd/bolt/export.go b/cmd/bolt/export.go
index 2689f32..9a0b112 100644
--- a/cmd/bolt/export.go
+++ b/cmd/bolt/export.go
@@ -42,7 +42,7 @@ func Export(path string) {
 		// Encode all buckets into JSON.
 		output, err := json.Marshal(root)
 		if err != nil {
-			return fmt.Errorf("encode: ", err)
+			return fmt.Errorf("encode: %s", err)
 		}
 		print(string(output))
 		return nil
diff --git a/node_test.go b/node_test.go
index f4bf4af..fa5d10f 100644
--- a/node_test.go
+++ b/node_test.go
@@ -54,7 +54,7 @@ func TestNode_read_LeafPage(t *testing.T) {
 
 	// Check that there are two inodes with correct data.
 	if !n.isLeaf {
-		t.Fatalf("expected leaf", n.isLeaf)
+		t.Fatal("expected leaf")
 	}
 	if len(n.inodes) != 2 {
 		t.Fatalf("exp=2; got=%d", len(n.inodes))