diff --git a/internal/http/request.go b/internal/http/request.go
index 6549e22..74f1030 100644
--- a/internal/http/request.go
+++ b/internal/http/request.go
@@ -3,6 +3,7 @@ package http
 import (
 	"net/http"
 	"net/url"
+	"slices"
 	"strings"
 
 	"github.com/nais/wonderwall/pkg/cookie"
@@ -34,15 +35,13 @@ func Accepts(r *http.Request, accepted ...string) bool {
 	// iterate over all Accept headers
 	for _, header := range r.Header.Values("Accept") {
 		// iterate over all comma-separated values in a single Accept header
-		for _, v := range strings.Split(header, ",") {
+		for v := range strings.SplitSeq(header, ",") {
 			v = strings.ToLower(v)
 			v = strings.TrimSpace(v)
 			v = strings.Split(v, ";")[0]
 
-			for _, accept := range accepted {
-				if v == accept {
-					return true
-				}
+			if slices.Contains(accepted, v) {
+				return true
 			}
 		}
 	}
diff --git a/pkg/handler/error_test.go b/pkg/handler/error_test.go
index 826b352..6f5324f 100644
--- a/pkg/handler/error_test.go
+++ b/pkg/handler/error_test.go
@@ -48,7 +48,7 @@ func TestHandler_Error(t *testing.T) {
 			r := idp.GetRequest(idp.RelyingPartyServer.URL)
 
 			// should be automatically redirected to the retry URI until maximum attempts are exhausted
-			for i := 0; i < errorhandler.MaxAutoRetryAttempts; i++ {
+			for range errorhandler.MaxAutoRetryAttempts {
 				w := httptest.NewRecorder()
 
 				test.fn(w, r, fmt.Errorf("some error"))
diff --git a/pkg/middleware/logentry.go b/pkg/middleware/logentry.go
index 313b98d..0ec00e5 100644
--- a/pkg/middleware/logentry.go
+++ b/pkg/middleware/logentry.go
@@ -85,7 +85,7 @@ func (l *logEntryAdapter) Write(status, bytes int, _ http.Header, elapsed time.D
 		Debugf("response: %d %s", status, http.StatusText(status))
 }
 
-func (l *logEntryAdapter) Panic(v interface{}, _ []byte) {
+func (l *logEntryAdapter) Panic(v any, _ []byte) {
 	stacktrace := "#"
 
 	fields := log.Fields{
diff --git a/pkg/mock/openid.go b/pkg/mock/openid.go
index d249100..57e507b 100644
--- a/pkg/mock/openid.go
+++ b/pkg/mock/openid.go
@@ -7,6 +7,7 @@ import (
 	"net/http/cookiejar"
 	"net/http/httptest"
 	"net/url"
+	"slices"
 	"strings"
 	"time"
 
@@ -309,13 +310,7 @@ func (ip *IdentityProviderHandler) parseAuthorizationRequest(query url.Values) (
 	for param, allowed := range allowedParamValues {
 		paramValue := query.Get(param)
 
-		found := false
-		for _, allowedValue := range allowed {
-			if paramValue == allowedValue {
-				found = true
-				break
-			}
-		}
+		found := slices.Contains(allowed, paramValue)
 
 		if !found {
 			return nil, fmt.Errorf("%q is an invalid value for %q, must be %q", paramValue, param, allowed)
diff --git a/pkg/openid/acr/acr.go b/pkg/openid/acr/acr.go
index 9f2ee18..2d483a4 100644
--- a/pkg/openid/acr/acr.go
+++ b/pkg/openid/acr/acr.go
@@ -2,6 +2,7 @@ package acr
 
 import (
 	"fmt"
+	"slices"
 )
 
 const (
@@ -40,10 +41,8 @@ func Validate(expected, actual string) error {
 		return fmt.Errorf("invalid acr: got %q, expected %q", actual, expected)
 	}
 
-	for _, accepted := range acceptedValues {
-		if actual == accepted {
-			return nil
-		}
+	if slices.Contains(acceptedValues, actual) {
+		return nil
 	}
 
 	return fmt.Errorf("invalid acr: got %q, must be one of %s", actual, acceptedValues)
diff --git a/pkg/openid/config/provider.go b/pkg/openid/config/provider.go
index 56b03fe..7ec6df0 100644
--- a/pkg/openid/config/provider.go
+++ b/pkg/openid/config/provider.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
+	"slices"
 
 	"github.com/lestrrat-go/jwx/v3/jwa"
 	log "github.com/sirupsen/logrus"
@@ -192,10 +193,8 @@ func (c *ProviderMetadata) validateLocaleValues(locale string) error {
 }
 
 func (c *ProviderMetadata) validateIDTokenSigningAlg(algorithm string) error {
-	for _, alg := range c.IDTokenSigningAlgValuesSupported {
-		if alg == algorithm {
-			return nil
-		}
+	if slices.Contains(c.IDTokenSigningAlgValuesSupported, algorithm) {
+		return nil
 	}
 
 	return fmt.Errorf("identity provider does not support '%s=%s', must be one of %s", config.OpenIDIDTokenSigningAlg, algorithm, c.IDTokenSigningAlgValuesSupported)
@@ -204,10 +203,5 @@ func (c *ProviderMetadata) validateIDTokenSigningAlg(algorithm string) error {
 type Supported []string
 
 func (in Supported) Contains(value string) bool {
-	for _, allowed := range in {
-		if allowed == value {
-			return true
-		}
-	}
-	return false
+	return slices.Contains(in, value)
 }
diff --git a/pkg/openid/oauth2.go b/pkg/openid/oauth2.go
index 92ab9ac..7908abf 100644
--- a/pkg/openid/oauth2.go
+++ b/pkg/openid/oauth2.go
@@ -2,6 +2,7 @@ package openid
 
 import (
 	"fmt"
+	"maps"
 	"net/url"
 
 	"github.com/nais/wonderwall/pkg/openid/scopes"
@@ -119,9 +120,7 @@ func (a RequestParams) URLValues() url.Values {
 // With returns a new RequestParams with the given RequestParams added.
 // Conflicting keys are overridden by the given RequestParams.
 func (a RequestParams) With(other RequestParams) RequestParams {
-	for key, val := range other {
-		a[key] = val
-	}
+	maps.Copy(a, other)
 
 	return a
 }
diff --git a/pkg/openid/tokens.go b/pkg/openid/tokens.go
index 34ad8a7..43b5073 100644
--- a/pkg/openid/tokens.go
+++ b/pkg/openid/tokens.go
@@ -240,7 +240,7 @@ func (in *IDToken) StringSliceClaim(claim string) ([]string, error) {
 	}
 
 	// the claim is a slice of interfaces...
-	claimValues, ok := gotClaim.([]interface{})
+	claimValues, ok := gotClaim.([]any)
 	if !ok {
 		return nil, fmt.Errorf("'%s' claim is not a slice", claim)
 	}