diff --git a/.golangci.yml b/.golangci.yml
index 11a419de0..3a6a29ef5 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -47,6 +47,12 @@ linters-settings:
 severity:
   default-severity: error
 
+skip-dirs:
+  - protogen/gen
+  - docs
+  - deployments
+  - changelog
+
 issues:
   exclude-use-default: true
   exclude-rules:
diff --git a/services/graph/pkg/service/v0/drives.go b/services/graph/pkg/service/v0/drives.go
index 8bed0119e..b03242c1f 100644
--- a/services/graph/pkg/service/v0/drives.go
+++ b/services/graph/pkg/service/v0/drives.go
@@ -33,6 +33,13 @@ import (
 	merrors "go-micro.dev/v4/errors"
 )
 
+const (
+	_spaceTypePersonal = "personal"
+	_spaceTypeProject  = "project"
+
+	_sortDescending = "desc"
+)
+
 var (
 	_invalidSpaceNameCharacters = []string{`/`, `\`, `.`, `:`, `?`, `*`, `"`, `>`, `<`, `|`}
 	_maxSpaceNameLength         = 255
@@ -253,8 +260,8 @@ func (g Graph) CreateDrive(w http.ResponseWriter, r *http.Request) {
 		driveType = *drive.DriveType
 	}
 	switch driveType {
-	case "", "project":
-		driveType = "project"
+	case "", _spaceTypeProject:
+		driveType = _spaceTypeProject
 	default:
 		logger.Debug().Str("type", driveType).Msg("could not create drive: drives of this type cannot be created via this api")
 		errorcode.InvalidRequest.Render(w, r, http.StatusBadRequest, "drives of this type cannot be created via this api")
@@ -275,7 +282,7 @@ func (g Graph) CreateDrive(w http.ResponseWriter, r *http.Request) {
 		csr.Opaque = utils.AppendPlainToOpaque(csr.Opaque, "spaceAlias", *drive.DriveAlias)
 	}
 
-	if driveType == "personal" {
+	if driveType == _spaceTypePersonal {
 		csr.Owner = us
 	}
 
@@ -911,7 +918,7 @@ func sortSpaces(req *godata.GoDataRequest, spaces []*libregraph.Drive) ([]*libre
 		return nil, errors.Errorf("we do not support <%s> as a order parameter", req.Query.OrderBy.OrderByItems[0].Field.Value)
 	}
 
-	if req.Query.OrderBy.OrderByItems[0].Order == "desc" {
+	if req.Query.OrderBy.OrderByItems[0].Order == _sortDescending {
 		sorter = sort.Reverse(sorter)
 	}
 	sort.Sort(sorter)
diff --git a/services/graph/pkg/service/v0/drives_test.go b/services/graph/pkg/service/v0/drives_test.go
index 2c13866e3..7cd084036 100644
--- a/services/graph/pkg/service/v0/drives_test.go
+++ b/services/graph/pkg/service/v0/drives_test.go
@@ -56,7 +56,7 @@ var sortTests = []sortTest{
 			Query: &godata.GoDataQuery{
 				OrderBy: &godata.GoDataOrderByQuery{
 					OrderByItems: []*godata.OrderByItem{
-						{Field: &godata.Token{Value: "name"}, Order: "desc"},
+						{Field: &godata.Token{Value: "name"}, Order: _sortDescending},
 					},
 				},
 			},
@@ -94,7 +94,7 @@ var sortTests = []sortTest{
 			Query: &godata.GoDataQuery{
 				OrderBy: &godata.GoDataOrderByQuery{
 					OrderByItems: []*godata.OrderByItem{
-						{Field: &godata.Token{Value: "lastModifiedDateTime"}, Order: "desc"},
+						{Field: &godata.Token{Value: "lastModifiedDateTime"}, Order: _sortDescending},
 					},
 				},
 			},
diff --git a/services/graph/pkg/service/v0/groups.go b/services/graph/pkg/service/v0/groups.go
index 3dd8abbe8..ce610496c 100644
--- a/services/graph/pkg/service/v0/groups.go
+++ b/services/graph/pkg/service/v0/groups.go
@@ -427,7 +427,7 @@ func sortGroups(req *godata.GoDataRequest, groups []*libregraph.Group) ([]*libre
 		return nil, fmt.Errorf("we do not support <%s> as a order parameter", req.Query.OrderBy.OrderByItems[0].Field.Value)
 	}
 
-	if req.Query.OrderBy.OrderByItems[0].Order == "desc" {
+	if req.Query.OrderBy.OrderByItems[0].Order == _sortDescending {
 		sorter = sort.Reverse(sorter)
 	}
 	sort.Sort(sorter)
diff --git a/services/graph/pkg/service/v0/users.go b/services/graph/pkg/service/v0/users.go
index dc9253ffa..fcfa882de 100644
--- a/services/graph/pkg/service/v0/users.go
+++ b/services/graph/pkg/service/v0/users.go
@@ -499,7 +499,7 @@ func sortUsers(req *godata.GoDataRequest, users []*libregraph.User) ([]*libregra
 		return nil, fmt.Errorf("we do not support <%s> as a order parameter", req.Query.OrderBy.OrderByItems[0].Field.Value)
 	}
 
-	if req.Query.OrderBy.OrderByItems[0].Order == "desc" {
+	if req.Query.OrderBy.OrderByItems[0].Order == _sortDescending {
 		sorter = sort.Reverse(sorter)
 	}
 	sort.Sort(sorter)
diff --git a/services/idp/pkg/command/server.go b/services/idp/pkg/command/server.go
index a17d0c42d..b8d299f3f 100644
--- a/services/idp/pkg/command/server.go
+++ b/services/idp/pkg/command/server.go
@@ -139,7 +139,7 @@ func ensureEncryptionSecretExists(path string) error {
 
 	f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0600)
 	if err != nil {
-		return nil
+		return err
 	}
 	defer f.Close()
 
@@ -175,7 +175,7 @@ func ensureSigningPrivateKeyExists(paths []string) error {
 
 		f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0600)
 		if err != nil {
-			return nil
+			return err
 		}
 		defer f.Close()
 
diff --git a/services/ocs/pkg/service/v0/groups.go b/services/ocs/pkg/service/v0/groups.go
index be933718e..0f1364226 100644
--- a/services/ocs/pkg/service/v0/groups.go
+++ b/services/ocs/pkg/service/v0/groups.go
@@ -2,35 +2,32 @@ package svc
 
 import (
 	"net/http"
-	"net/url"
 
-	"github.com/go-chi/chi/v5"
 	"github.com/owncloud/ocis/v2/services/ocs/pkg/service/v0/data"
 	"github.com/owncloud/ocis/v2/services/ocs/pkg/service/v0/response"
 )
 
+const (
+	_backendCS3 = "cs3"
+)
+
 // ListUserGroups lists a users groups
 func (o Ocs) ListUserGroups(w http.ResponseWriter, r *http.Request) {
-	userid := chi.URLParam(r, "userid")
-	userid, _ = url.PathUnescape(userid)
 	switch o.config.AccountBackend {
-	case "cs3":
+	case _backendCS3:
 		// TODO
 		o.mustRender(w, r, response.DataRender(&data.Groups{}))
-		return
 	default:
 		o.logger.Fatal().Msgf("Invalid accounts backend type '%s'", o.config.AccountBackend)
 	}
-	return
 }
 
 // AddToGroup adds a user to a group
 func (o Ocs) AddToGroup(w http.ResponseWriter, r *http.Request) {
 	switch o.config.AccountBackend {
-	case "cs3":
+	case _backendCS3:
 		// TODO
 		o.cs3WriteNotSupported(w, r)
-		return
 	default:
 		o.logger.Fatal().Msgf("Invalid accounts backend type '%s'", o.config.AccountBackend)
 	}
@@ -39,10 +36,9 @@ func (o Ocs) AddToGroup(w http.ResponseWriter, r *http.Request) {
 // RemoveFromGroup removes a user from a group
 func (o Ocs) RemoveFromGroup(w http.ResponseWriter, r *http.Request) {
 	switch o.config.AccountBackend {
-	case "cs3":
+	case _backendCS3:
 		// TODO
 		o.cs3WriteNotSupported(w, r)
-		return
 	default:
 		o.logger.Fatal().Msgf("Invalid accounts backend type '%s'", o.config.AccountBackend)
 	}
@@ -51,23 +47,20 @@ func (o Ocs) RemoveFromGroup(w http.ResponseWriter, r *http.Request) {
 // ListGroups lists all groups
 func (o Ocs) ListGroups(w http.ResponseWriter, r *http.Request) {
 	switch o.config.AccountBackend {
-	case "cs3":
+	case _backendCS3:
 		// TODO
 		o.mustRender(w, r, response.DataRender(&data.Groups{}))
-		return
 	default:
 		o.logger.Fatal().Msgf("Invalid accounts backend type '%s'", o.config.AccountBackend)
 	}
-	return
 }
 
 // AddGroup adds a group
 // oC10 implementation: https://github.com/owncloud/core/blob/762780a23c9eadda4fb5fa8db99eba66a5100b6e/apps/provisioning_api/lib/Groups.php#L126-L154
 func (o Ocs) AddGroup(w http.ResponseWriter, r *http.Request) {
 	switch o.config.AccountBackend {
-	case "cs3":
+	case _backendCS3:
 		o.cs3WriteNotSupported(w, r)
-		return
 	default:
 		o.logger.Fatal().Msgf("Invalid accounts backend type '%s'", o.config.AccountBackend)
 	}
@@ -76,9 +69,8 @@ func (o Ocs) AddGroup(w http.ResponseWriter, r *http.Request) {
 // DeleteGroup deletes a group
 func (o Ocs) DeleteGroup(w http.ResponseWriter, r *http.Request) {
 	switch o.config.AccountBackend {
-	case "cs3":
+	case _backendCS3:
 		o.cs3WriteNotSupported(w, r)
-		return
 	default:
 		o.logger.Fatal().Msgf("Invalid accounts backend type '%s'", o.config.AccountBackend)
 	}
@@ -87,12 +79,10 @@ func (o Ocs) DeleteGroup(w http.ResponseWriter, r *http.Request) {
 // GetGroupMembers lists all members of a group
 func (o Ocs) GetGroupMembers(w http.ResponseWriter, r *http.Request) {
 	switch o.config.AccountBackend {
-	case "cs3":
+	case _backendCS3:
 		// TODO
 		o.mustRender(w, r, response.DataRender(&data.Users{}))
-		return
 	default:
 		o.logger.Fatal().Msgf("Invalid accounts backend type '%s'", o.config.AccountBackend)
 	}
-	return
 }
diff --git a/services/ocs/pkg/service/v0/users.go b/services/ocs/pkg/service/v0/users.go
index 84f7ab52f..df788d910 100644
--- a/services/ocs/pkg/service/v0/users.go
+++ b/services/ocs/pkg/service/v0/users.go
@@ -6,7 +6,6 @@ import (
 	"encoding/hex"
 	"net/http"
 	"net/url"
-	"strings"
 
 	storemsg "github.com/owncloud/ocis/v2/protogen/gen/ocis/messages/store/v0"
 	storesvc "github.com/owncloud/ocis/v2/protogen/gen/ocis/services/store/v0"
@@ -37,7 +36,6 @@ func (o Ocs) GetSelf(w http.ResponseWriter, r *http.Request) {
 		GIDNumber:         u.GidNumber,
 	}
 	o.mustRender(w, r, response.DataRender(d))
-	return
 }
 
 // GetUser returns the user with the given userid
@@ -237,11 +235,6 @@ func (o Ocs) ListUsers(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
-// escapeValue escapes all special characters in the value
-func escapeValue(value string) string {
-	return strings.ReplaceAll(value, "'", "''")
-}
-
 func (o Ocs) fetchAccountFromCS3Backend(ctx context.Context, name string) (*cs3.User, error) {
 	backend := o.getCS3Backend()
 	u, _, err := backend.GetUserByClaims(ctx, "username", name, false)
@@ -254,5 +247,4 @@ func (o Ocs) fetchAccountFromCS3Backend(ctx context.Context, name string) (*cs3.
 func (o Ocs) cs3WriteNotSupported(w http.ResponseWriter, r *http.Request) {
 	o.logger.Warn().Msg("the CS3 backend does not support adding or updating users")
 	o.NotImplementedStub(w, r)
-	return
 }
diff --git a/services/settings/pkg/store/filesystem/assignments.go b/services/settings/pkg/store/filesystem/assignments.go
index 350a04cb1..7e997c9d8 100644
--- a/services/settings/pkg/store/filesystem/assignments.go
+++ b/services/settings/pkg/store/filesystem/assignments.go
@@ -15,7 +15,7 @@ func (s Store) ListRoleAssignments(accountUUID string) ([]*settingsmsg.UserRoleA
 	assignmentsFolder := s.buildFolderPathForRoleAssignments(false)
 	assignmentFiles, err := os.ReadDir(assignmentsFolder)
 	if err != nil {
-		return records, nil
+		return nil, nil
 	}
 
 	for _, assignmentFile := range assignmentFiles {
diff --git a/services/settings/pkg/store/filesystem/bundles.go b/services/settings/pkg/store/filesystem/bundles.go
index 17bce7bc9..513bff747 100644
--- a/services/settings/pkg/store/filesystem/bundles.go
+++ b/services/settings/pkg/store/filesystem/bundles.go
@@ -23,7 +23,7 @@ func (s Store) ListBundles(bundleType settingsmsg.Bundle_Type, bundleIDs []strin
 	bundlesFolder := s.buildFolderPathForBundles(false)
 	bundleFiles, err := os.ReadDir(bundlesFolder)
 	if err != nil {
-		return []*settingsmsg.Bundle{}, nil
+		return nil, err
 	}
 
 	records := make([]*settingsmsg.Bundle, 0, len(bundleFiles))
@@ -133,7 +133,7 @@ func (s Store) AddSettingToBundle(bundleID string, setting *settingsmsg.Setting)
 func (s Store) RemoveSettingFromBundle(bundleID string, settingID string) error {
 	bundle, err := s.ReadBundle(bundleID)
 	if err != nil {
-		return nil
+		return err
 	}
 	if ok := removeSetting(bundle, settingID); ok {
 		if _, err := s.WriteBundle(bundle); err != nil {
diff --git a/services/settings/pkg/store/filesystem/values.go b/services/settings/pkg/store/filesystem/values.go
index b0a26ebff..230a05055 100644
--- a/services/settings/pkg/store/filesystem/values.go
+++ b/services/settings/pkg/store/filesystem/values.go
@@ -18,7 +18,7 @@ func (s Store) ListValues(bundleID, accountUUID string) ([]*settingsmsg.Value, e
 	valuesFolder := s.buildFolderPathForValues(false)
 	valueFiles, err := os.ReadDir(valuesFolder)
 	if err != nil {
-		return []*settingsmsg.Value{}, nil
+		return nil, err
 	}
 
 	records := make([]*settingsmsg.Value, 0, len(valueFiles))
@@ -71,7 +71,7 @@ func (s Store) ReadValueByUniqueIdentifiers(accountUUID, settingID string) (*set
 			s.Logger.Debug().Msgf("reading contents from file: %v", filepath.Join(valuesFolder, files[i].Name()))
 			if err := s.parseRecordFromFile(&r, filepath.Join(valuesFolder, files[i].Name())); err != nil {
 				s.Logger.Debug().Msgf("match found: %v", filepath.Join(valuesFolder, files[i].Name()))
-				return &settingsmsg.Value{}, nil
+				return nil, err
 			}
 
 			// if value saved without accountUUID, then it's a global value
diff --git a/services/sharing/pkg/config/parser/parse.go b/services/sharing/pkg/config/parser/parse.go
index 32cc5624c..c22fb4c0a 100644
--- a/services/sharing/pkg/config/parser/parse.go
+++ b/services/sharing/pkg/config/parser/parse.go
@@ -11,6 +11,10 @@ import (
 	"github.com/owncloud/ocis/v2/ocis-pkg/config/envdecode"
 )
 
+const (
+	_backendCS3 = "cs3"
+)
+
 // ParseConfig loads configuration from known paths.
 func ParseConfig(cfg *config.Config) error {
 	_, err := ociscfg.BindSourcesToStructs(cfg.Service.Name, cfg)
@@ -38,19 +42,19 @@ func Validate(cfg *config.Config) error {
 		return shared.MissingJWTTokenError(cfg.Service.Name)
 	}
 
-	if cfg.PublicSharingDriver == "cs3" && cfg.PublicSharingDrivers.CS3.SystemUserAPIKey == "" {
+	if cfg.PublicSharingDriver == _backendCS3 && cfg.PublicSharingDrivers.CS3.SystemUserAPIKey == "" {
 		return shared.MissingSystemUserApiKeyError(cfg.Service.Name)
 	}
 
-	if cfg.PublicSharingDriver == "cs3" && cfg.PublicSharingDrivers.CS3.SystemUserID == "" {
+	if cfg.PublicSharingDriver == _backendCS3 && cfg.PublicSharingDrivers.CS3.SystemUserID == "" {
 		return shared.MissingSystemUserID(cfg.Service.Name)
 	}
 
-	if cfg.UserSharingDriver == "cs3" && cfg.UserSharingDrivers.CS3.SystemUserAPIKey == "" {
+	if cfg.UserSharingDriver == _backendCS3 && cfg.UserSharingDrivers.CS3.SystemUserAPIKey == "" {
 		return shared.MissingSystemUserApiKeyError(cfg.Service.Name)
 	}
 
-	if cfg.UserSharingDriver == "cs3" && cfg.UserSharingDrivers.CS3.SystemUserID == "" {
+	if cfg.UserSharingDriver == _backendCS3 && cfg.UserSharingDrivers.CS3.SystemUserID == "" {
 		return shared.MissingSystemUserID(cfg.Service.Name)
 	}
 
diff --git a/services/thumbnails/pkg/service/grpc/v0/service.go b/services/thumbnails/pkg/service/grpc/v0/service.go
index e6cc0cac5..4420258ad 100644
--- a/services/thumbnails/pkg/service/grpc/v0/service.go
+++ b/services/thumbnails/pkg/service/grpc/v0/service.go
@@ -82,13 +82,11 @@ func (g Thumbnail) GetThumbnail(ctx context.Context, req *thumbnailssvc.GetThumb
 	}
 	generator, err := thumbnail.GeneratorForType(tType)
 	if err != nil {
-		g.logger.Debug().Str("thumbnail_type", tType).Msg("unsupported thumbnail type")
-		return nil
+		return merrors.BadRequest(g.serviceID, "unsupported thumbnail type")
 	}
 	encoder, err := thumbnail.EncoderForType(tType)
 	if err != nil {
-		g.logger.Debug().Str("thumbnail_type", tType).Msg("unsupported thumbnail type")
-		return nil
+		return merrors.BadRequest(g.serviceID, "unsupported thumbnail type")
 	}
 
 	var key string
diff --git a/services/webdav/pkg/propfind/propfind.go b/services/webdav/pkg/propfind/propfind.go
index 3bc8e4f9c..5a488eec2 100644
--- a/services/webdav/pkg/propfind/propfind.go
+++ b/services/webdav/pkg/propfind/propfind.go
@@ -10,10 +10,6 @@ import (
 	"github.com/owncloud/ocis/v2/services/webdav/pkg/prop"
 )
 
-const (
-	_spaceTypeProject = "project"
-)
-
 type countingReader struct {
 	n int
 	r io.Reader