diff --git a/database/storage/badger/badger.go b/database/storage/badger/badger.go
index 6cc23ea..da2276d 100644
--- a/database/storage/badger/badger.go
+++ b/database/storage/badger/badger.go
@@ -21,7 +21,7 @@ type Badger struct {
 }
 
 func init() {
-	storage.Register("badger", NewBadger)
+	_ = storage.Register("badger", NewBadger)
 }
 
 // NewBadger opens/creates a badger database.
@@ -190,7 +190,7 @@ func (b *Badger) Injected() bool {
 
 // Maintain runs a light maintenance operation on the database.
 func (b *Badger) Maintain() error {
-	b.db.RunValueLogGC(0.7)
+	_ = b.db.RunValueLogGC(0.7)
 	return nil
 }
 
diff --git a/database/storage/badger/badger_test.go b/database/storage/badger/badger_test.go
index 32d8774..47e10b6 100644
--- a/database/storage/badger/badger_test.go
+++ b/database/storage/badger/badger_test.go
@@ -1,3 +1,4 @@
+//nolint:unparam,maligned
 package badger
 
 import (
@@ -13,7 +14,7 @@ import (
 
 type TestRecord struct {
 	record.Base
-	lock sync.Mutex
+	sync.Mutex
 	S    string
 	I    int
 	I8   int8
@@ -30,12 +31,6 @@ type TestRecord struct {
 	B    bool
 }
 
-func (tr *TestRecord) Lock() {
-}
-
-func (tr *TestRecord) Unlock() {
-}
-
 func TestBadger(t *testing.T) {
 	testDir, err := ioutil.TempDir("", "testing-")
 	if err != nil {
diff --git a/database/storage/bbolt/bbolt.go b/database/storage/bbolt/bbolt.go
index c1d487b..d37bf60 100644
--- a/database/storage/bbolt/bbolt.go
+++ b/database/storage/bbolt/bbolt.go
@@ -26,7 +26,7 @@ type BBolt struct {
 }
 
 func init() {
-	storage.Register("bbolt", NewBBolt)
+	_ = storage.Register("bbolt", NewBBolt)
 }
 
 // NewBBolt opens/creates a bbolt database.
diff --git a/database/storage/bbolt/bbolt_test.go b/database/storage/bbolt/bbolt_test.go
index 631d89b..5264f56 100644
--- a/database/storage/bbolt/bbolt_test.go
+++ b/database/storage/bbolt/bbolt_test.go
@@ -1,3 +1,4 @@
+//nolint:unparam,maligned
 package bbolt
 
 import (
@@ -13,7 +14,7 @@ import (
 
 type TestRecord struct {
 	record.Base
-	lock sync.Mutex
+	sync.Mutex
 	S    string
 	I    int
 	I8   int8
@@ -30,12 +31,6 @@ type TestRecord struct {
 	B    bool
 }
 
-func (tr *TestRecord) Lock() {
-}
-
-func (tr *TestRecord) Unlock() {
-}
-
 func TestBadger(t *testing.T) {
 	testDir, err := ioutil.TempDir("", "testing-")
 	if err != nil {
diff --git a/database/storage/fstree/fstree.go b/database/storage/fstree/fstree.go
index af723d5..fa160de 100644
--- a/database/storage/fstree/fstree.go
+++ b/database/storage/fstree/fstree.go
@@ -35,7 +35,7 @@ type FSTree struct {
 }
 
 func init() {
-	storage.Register("fstree", NewFSTree)
+	_ = storage.Register("fstree", NewFSTree)
 }
 
 // NewFSTree returns a (new) FSTree database.
@@ -160,15 +160,14 @@ func (fst *FSTree) Query(q *query.Query, local, internal bool) (*iterator.Iterat
 	}
 	fileInfo, err := os.Stat(walkPrefix)
 	var walkRoot string
-	if err == nil {
-		if fileInfo.IsDir() {
-			walkRoot = walkPrefix
-		} else {
-			walkRoot = filepath.Dir(walkPrefix)
-		}
-	} else if os.IsNotExist(err) {
+	switch {
+	case err == nil && fileInfo.IsDir():
+		walkRoot = walkPrefix
+	case err == nil:
 		walkRoot = filepath.Dir(walkPrefix)
-	} else {
+	case os.IsNotExist(err):
+		walkRoot = filepath.Dir(walkPrefix)
+	default: // err != nil
 		return nil, fmt.Errorf("fstree: could not stat query root %s: %s", walkPrefix, err)
 	}
 
@@ -279,7 +278,7 @@ func writeFile(filename string, data []byte, perm os.FileMode) error {
 	if err != nil {
 		return err
 	}
-	defer t.Cleanup()
+	defer t.Cleanup() //nolint:errcheck
 
 	// Set permissions before writing data, in case the data is sensitive.
 	if !onWindows {
diff --git a/database/storage/sinkhole/sinkhole.go b/database/storage/sinkhole/sinkhole.go
index 0135817..9c51d29 100644
--- a/database/storage/sinkhole/sinkhole.go
+++ b/database/storage/sinkhole/sinkhole.go
@@ -15,7 +15,7 @@ type Sinkhole struct {
 }
 
 func init() {
-	storage.Register("sinkhole", NewSinkhole)
+	_ = storage.Register("sinkhole", NewSinkhole)
 }
 
 // NewSinkhole creates a dummy database.