diff --git a/cmd/dex/serve.go b/cmd/dex/serve.go
index 91b0fd22..1733a5c8 100644
--- a/cmd/dex/serve.go
+++ b/cmd/dex/serve.go
@@ -116,7 +116,7 @@ func serve(cmd *cobra.Command, args []string) error {
 			if err != nil {
 				return fmt.Errorf("invalid config: reading from client CA file: %v", err)
 			}
-			if cPool.AppendCertsFromPEM(clientCert) != true {
+			if !cPool.AppendCertsFromPEM(clientCert) {
 				return errors.New("invalid config: failed to parse client CA")
 			}
 
diff --git a/connector/github/github.go b/connector/github/github.go
index 35fe6b92..6fc4cc03 100644
--- a/connector/github/github.go
+++ b/connector/github/github.go
@@ -443,7 +443,7 @@ func (c *githubConnector) userOrgs(ctx context.Context, client *http.Client) ([]
 // userOrgTeams retrieves teams which current user belongs to.
 // Method returns a map where key is an org name and value list of teams under the org.
 func (c *githubConnector) userOrgTeams(ctx context.Context, client *http.Client) (map[string][]string, error) {
-	groups := make(map[string][]string, 0)
+	groups := make(map[string][]string)
 	apiURL := c.apiURL + "/user/teams"
 	for {
 		// https://developer.github.com/v3/orgs/teams/#list-user-teams
diff --git a/connector/gitlab/gitlab_test.go b/connector/gitlab/gitlab_test.go
index f56621fb..331b486e 100644
--- a/connector/gitlab/gitlab_test.go
+++ b/connector/gitlab/gitlab_test.go
@@ -185,13 +185,11 @@ func TestLoginWithTeamNonWhitelisted(t *testing.T) {
 }
 
 func newTestServer(responses map[string]interface{}) *httptest.Server {
-	var s *httptest.Server
-	s = httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	return httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		response := responses[r.RequestURI]
 		w.Header().Add("Content-Type", "application/json")
 		json.NewEncoder(w).Encode(response)
 	}))
-	return s
 }
 
 func newClient() *http.Client {
diff --git a/connector/keystone/keystone.go b/connector/keystone/keystone.go
index 0a2440db..dc74a01f 100644
--- a/connector/keystone/keystone.go
+++ b/connector/keystone/keystone.go
@@ -241,6 +241,9 @@ func (p *conn) getUserGroups(ctx context.Context, userID string, token string) (
 	// https://developer.openstack.org/api-ref/identity/v3/#list-groups-to-which-a-user-belongs
 	groupsURL := p.Host + "/v3/users/" + userID + "/groups"
 	req, err := http.NewRequest("GET", groupsURL, nil)
+	if err != nil {
+		return nil, err
+	}
 	req.Header.Set("X-Auth-Token", token)
 	req = req.WithContext(ctx)
 	resp, err := client.Do(req)
diff --git a/connector/oidc/oidc.go b/connector/oidc/oidc.go
index 327b1079..4a64df8b 100644
--- a/connector/oidc/oidc.go
+++ b/connector/oidc/oidc.go
@@ -148,7 +148,6 @@ type oidcConnector struct {
 	redirectURI               string
 	oauth2Config              *oauth2.Config
 	verifier                  *oidc.IDTokenVerifier
-	ctx                       context.Context
 	cancel                    context.CancelFunc
 	logger                    log.Logger
 	hostedDomains             []string
diff --git a/connector/saml/saml.go b/connector/saml/saml.go
index 3358583d..7bc6730e 100644
--- a/connector/saml/saml.go
+++ b/connector/saml/saml.go
@@ -20,6 +20,7 @@ import (
 	"github.com/russellhaering/goxmldsig/etreeutils"
 )
 
+// nolint
 const (
 	bindingRedirect = "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect"
 	bindingPOST     = "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST"
diff --git a/connector/saml/saml_test.go b/connector/saml/saml_test.go
index 4497d059..d9aaf3f4 100644
--- a/connector/saml/saml_test.go
+++ b/connector/saml/saml_test.go
@@ -424,14 +424,6 @@ func TestConfigCAData(t *testing.T) {
 	}
 }
 
-const (
-	defaultSSOIssuer   = "http://www.okta.com/exk91cb99lKkKSYoy0h7"
-	defaultRedirectURI = "http://localhost:5556/dex/callback"
-
-	// Response ID embedded in our testdata.
-	testDataResponseID = "_fd1b3ef9-ec09-44a7-a66b-0d39c250f6a0"
-)
-
 // Deprecated: Use testing framework established above.
 func runVerify(t *testing.T, ca string, resp string, shouldSucceed bool) {
 	cert, err := loadCert(ca)
@@ -458,27 +450,6 @@ func runVerify(t *testing.T, ca string, resp string, shouldSucceed bool) {
 	}
 }
 
-// Deprecated: Use testing framework established above.
-func newProvider(ssoIssuer string, redirectURI string) *provider {
-	if ssoIssuer == "" {
-		ssoIssuer = defaultSSOIssuer
-	}
-	if redirectURI == "" {
-		redirectURI = defaultRedirectURI
-	}
-	now, _ := time.Parse(time.RFC3339, "2017-01-24T20:48:41Z")
-	timeFunc := func() time.Time { return now }
-	return &provider{
-		ssoIssuer:    ssoIssuer,
-		ssoURL:       "http://idp.org/saml/sso",
-		now:          timeFunc,
-		usernameAttr: "user",
-		emailAttr:    "email",
-		redirectURI:  redirectURI,
-		logger:       logrus.New(),
-	}
-}
-
 func TestVerify(t *testing.T) {
 	runVerify(t, "testdata/okta-ca.pem", "testdata/okta-resp.xml", true)
 }
diff --git a/server/oauth2.go b/server/oauth2.go
index 79c4bf1a..6104b549 100644
--- a/server/oauth2.go
+++ b/server/oauth2.go
@@ -89,6 +89,7 @@ func tokenErr(w http.ResponseWriter, typ, description string, statusCode int) er
 	return nil
 }
 
+// nolint
 const (
 	errInvalidRequest          = "invalid_request"
 	errUnauthorizedClient      = "unauthorized_client"
diff --git a/server/rotation.go b/server/rotation.go
index 579fe3d1..464dccf0 100644
--- a/server/rotation.go
+++ b/server/rotation.go
@@ -92,7 +92,6 @@ func (s *Server) startKeyRotation(ctx context.Context, strategy rotationStrategy
 			}
 		}
 	}()
-	return
 }
 
 func (k keyRotater) rotate() error {
diff --git a/server/server.go b/server/server.go
index 69b4d0d7..e1258151 100644
--- a/server/server.go
+++ b/server/server.go
@@ -426,7 +426,6 @@ func (s *Server) startGarbageCollection(ctx context.Context, frequency time.Dura
 			}
 		}
 	}()
-	return
 }
 
 // ConnectorConfig is a configuration that can open a connector.
diff --git a/server/server_test.go b/server/server_test.go
index 2b4c6453..6759f240 100644
--- a/server/server_test.go
+++ b/server/server_test.go
@@ -552,7 +552,6 @@ func TestOAuth2CodeFlow(t *testing.T) {
 					t.Errorf("state did not match, want=%q got=%q", state, gotState)
 				}
 				w.WriteHeader(http.StatusOK)
-				return
 			}))
 
 			defer oauth2Client.Close()
@@ -1204,7 +1203,6 @@ func TestRefreshTokenFlow(t *testing.T) {
 			t.Errorf("state did not match, want=%q got=%q", state, gotState)
 		}
 		w.WriteHeader(http.StatusOK)
-		return
 	}))
 	defer oauth2Client.server.Close()
 
@@ -1242,8 +1240,7 @@ func TestRefreshTokenFlow(t *testing.T) {
 	}
 
 	// try to refresh expired token with old refresh token.
-	newToken, err := oauth2Client.config.TokenSource(ctx, tok).Token()
-	if newToken != nil {
-		t.Errorf("Token refreshed with invalid refresh token.")
+	if _, err := oauth2Client.config.TokenSource(ctx, tok).Token(); err == nil {
+		t.Errorf("Token refreshed with invalid refresh token, error expected.")
 	}
 }
diff --git a/storage/etcd/types.go b/storage/etcd/types.go
index 8d34e0da..0d8f521a 100644
--- a/storage/etcd/types.go
+++ b/storage/etcd/types.go
@@ -183,24 +183,6 @@ type Keys struct {
 	NextRotation     time.Time                 `json:"next_rotation"`
 }
 
-func fromStorageKeys(keys storage.Keys) Keys {
-	return Keys{
-		SigningKey:       keys.SigningKey,
-		SigningKeyPub:    keys.SigningKeyPub,
-		VerificationKeys: keys.VerificationKeys,
-		NextRotation:     keys.NextRotation,
-	}
-}
-
-func toStorageKeys(keys Keys) storage.Keys {
-	return storage.Keys{
-		SigningKey:       keys.SigningKey,
-		SigningKeyPub:    keys.SigningKeyPub,
-		VerificationKeys: keys.VerificationKeys,
-		NextRotation:     keys.NextRotation,
-	}
-}
-
 // OfflineSessions is a mirrored struct from storage with JSON struct tags
 type OfflineSessions struct {
 	UserID  string                              `json:"user_id,omitempty"`
diff --git a/storage/sql/config.go b/storage/sql/config.go
index c33fcf20..0095b57d 100644
--- a/storage/sql/config.go
+++ b/storage/sql/config.go
@@ -72,6 +72,7 @@ func (s *SQLite3) open(logger log.Logger) (*conn, error) {
 	return c, nil
 }
 
+// nolint
 const (
 	// postgres SSL modes
 	pgSSLDisable    = "disable"
@@ -80,6 +81,7 @@ const (
 	pgSSLVerifyFull = "verify-full"
 )
 
+// nolint
 const (
 	// MySQL SSL modes
 	mysqlSSLTrue       = "true"