diff --git a/api.go b/api.go
index 8e3a22b..d391726 100644
--- a/api.go
+++ b/api.go
@@ -7,7 +7,9 @@ package api
 import (
 	"context"
 	"errors"
+	"iter"
 	"net/http"
+	"slices"
 	"time"
 
 	"github.com/gin-contrib/expvar"
@@ -59,6 +61,11 @@ func (e *Engine) Groups() []RouteGroup {
 	return e.groups
 }
 
+// GroupsIter returns an iterator over all registered route groups.
+func (e *Engine) GroupsIter() iter.Seq[RouteGroup] {
+	return slices.Values(e.groups)
+}
+
 // Register adds a route group to the engine.
 func (e *Engine) Register(group RouteGroup) {
 	e.groups = append(e.groups, group)
@@ -76,6 +83,21 @@ func (e *Engine) Channels() []string {
 	return channels
 }
 
+// ChannelsIter returns an iterator over WebSocket channel names from registered StreamGroups.
+func (e *Engine) ChannelsIter() iter.Seq[string] {
+	return func(yield func(string) bool) {
+		for _, g := range e.groups {
+			if sg, ok := g.(StreamGroup); ok {
+				for _, c := range sg.Channels() {
+					if !yield(c) {
+						return
+					}
+				}
+			}
+		}
+	}
+}
+
 // Handler builds the Gin engine and returns it as an http.Handler.
 // Each call produces a fresh handler reflecting the current set of groups.
 func (e *Engine) Handler() http.Handler {
diff --git a/bridge.go b/bridge.go
index 9b2a7e0..79e2e78 100644
--- a/bridge.go
+++ b/bridge.go
@@ -2,7 +2,11 @@
 
 package api
 
-import "github.com/gin-gonic/gin"
+import (
+	"iter"
+
+	"github.com/gin-gonic/gin"
+)
 
 // ToolDescriptor describes a tool that can be exposed as a REST endpoint.
 type ToolDescriptor struct {
@@ -73,6 +77,30 @@ func (b *ToolBridge) Describe() []RouteDescription {
 	return descs
 }
 
+// DescribeIter returns an iterator over OpenAPI route descriptions for all registered tools.
+func (b *ToolBridge) DescribeIter() iter.Seq[RouteDescription] {
+	return func(yield func(RouteDescription) bool) {
+		for _, t := range b.tools {
+			tags := []string{t.descriptor.Group}
+			if t.descriptor.Group == "" {
+				tags = []string{b.name}
+			}
+			rd := RouteDescription{
+				Method:      "POST",
+				Path:        "/" + t.descriptor.Name,
+				Summary:     t.descriptor.Description,
+				Description: t.descriptor.Description,
+				Tags:        tags,
+				RequestBody: t.descriptor.InputSchema,
+				Response:    t.descriptor.OutputSchema,
+			}
+			if !yield(rd) {
+				return
+			}
+		}
+	}
+}
+
 // Tools returns all registered tool descriptors.
 func (b *ToolBridge) Tools() []ToolDescriptor {
 	descs := make([]ToolDescriptor, len(b.tools))
@@ -81,3 +109,14 @@ func (b *ToolBridge) Tools() []ToolDescriptor {
 	}
 	return descs
 }
+
+// ToolsIter returns an iterator over all registered tool descriptors.
+func (b *ToolBridge) ToolsIter() iter.Seq[ToolDescriptor] {
+	return func(yield func(ToolDescriptor) bool) {
+		for _, t := range b.tools {
+			if !yield(t.descriptor) {
+				return
+			}
+		}
+	}
+}
diff --git a/cmd/api/cmd_sdk.go b/cmd/api/cmd_sdk.go
index 58cb7ce..6dd2cba 100644
--- a/cmd/api/cmd_sdk.go
+++ b/cmd/api/cmd_sdk.go
@@ -65,9 +65,11 @@ func addSDKCommand(parent *cli.Command) {
 		}
 
 		// Generate for each language.
-		languages := strings.Split(lang, ",")
-		for _, l := range languages {
+		for l := range strings.SplitSeq(lang, ",") {
 			l = strings.TrimSpace(l)
+			if l == "" {
+				continue
+			}
 			fmt.Fprintf(os.Stderr, "Generating %s SDK...\n", l)
 			if err := gen.Generate(context.Background(), l); err != nil {
 				return fmt.Errorf("generate %s: %w", l, err)
diff --git a/codegen.go b/codegen.go
index ff31a10..c3d25fe 100644
--- a/codegen.go
+++ b/codegen.go
@@ -5,25 +5,27 @@ package api
 import (
 	"context"
 	"fmt"
+	"iter"
+	"maps"
 	"os"
 	"os/exec"
 	"path/filepath"
-	"sort"
+	"slices"
 )
 
 // Supported SDK target languages.
 var supportedLanguages = map[string]string{
 	"go":               "go",
-	"typescript-fetch":  "typescript-fetch",
-	"typescript-axios":  "typescript-axios",
-	"python":            "python",
-	"java":              "java",
-	"csharp":            "csharp-netcore",
-	"ruby":              "ruby",
-	"swift":             "swift5",
-	"kotlin":            "kotlin",
-	"rust":              "rust",
-	"php":               "php",
+	"typescript-fetch": "typescript-fetch",
+	"typescript-axios": "typescript-axios",
+	"python":           "python",
+	"java":             "java",
+	"csharp":           "csharp-netcore",
+	"ruby":             "ruby",
+	"swift":            "swift5",
+	"kotlin":           "kotlin",
+	"rust":             "rust",
+	"php":              "php",
 }
 
 // SDKGenerator wraps openapi-generator-cli for SDK generation.
@@ -90,10 +92,10 @@ func (g *SDKGenerator) Available() bool {
 // SupportedLanguages returns the list of supported SDK target languages
 // in sorted order for deterministic output.
 func SupportedLanguages() []string {
-	langs := make([]string, 0, len(supportedLanguages))
-	for k := range supportedLanguages {
-		langs = append(langs, k)
-	}
-	sort.Strings(langs)
-	return langs
+	return slices.Sorted(maps.Keys(supportedLanguages))
+}
+
+// SupportedLanguagesIter returns an iterator over supported SDK target languages in sorted order.
+func SupportedLanguagesIter() iter.Seq[string] {
+	return slices.Values(SupportedLanguages())
 }
diff --git a/go.sum b/go.sum
index b1f8fdb..5ff5a09 100644
--- a/go.sum
+++ b/go.sum
@@ -1,6 +1,9 @@
 forge.lthn.ai/core/cli v0.0.1 h1:nqpc4Tv8a4H/ERei+/71DVQxkCFU8HPFJP4120qPXgk=
+forge.lthn.ai/core/cli v0.0.1/go.mod h1:xa3Nqw3sUtYYJ1k+1jYul18tgs6sBevCUsGsHJI1hHA=
 forge.lthn.ai/core/go v0.0.1 h1:ubk4nmkA3treOUNgPS28wKd1jB6cUlEQUV7jDdGa3zM=
+forge.lthn.ai/core/go v0.0.1/go.mod h1:59YsnuMaAGQUxIhX68oK2/HnhQJEPWL1iEZhDTrNCbY=
 forge.lthn.ai/core/go-crypt v0.0.1 h1:fmFc2SJ/VOXDRjkcYoLWfL7lI4HfPJeVS/Na6zHHcvw=
+forge.lthn.ai/core/go-crypt v0.0.1/go.mod h1:/j/rUN2ZMV7x1B5BYxH3QdwkgZg0HNBw5XuyFZeyxBY=
 github.com/99designs/gqlgen v0.17.87 h1:pSnCIMhBQezAE8bc1GNmfdLXFmnWtWl1GRDFEE/nHP8=
 github.com/99designs/gqlgen v0.17.87/go.mod h1:fK05f1RqSNfQpd4CfW5qk/810Tqi4/56Wf6Nem0khAg=
 github.com/KyleBanks/depth v1.2.1 h1:5h8fQADFrWtarTdtDudMmGsC7GPbOAu6RVB3ffsVFHc=
@@ -108,18 +111,30 @@ github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ4
 github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/go-openapi/jsonpointer v0.22.4 h1:dZtK82WlNpVLDW2jlA1YCiVJFVqkED1MegOUy9kR5T4=
+github.com/go-openapi/jsonpointer v0.22.4/go.mod h1:elX9+UgznpFhgBuaMQ7iu4lvvX1nvNsesQ3oxmYTw80=
 github.com/go-openapi/jsonreference v0.21.2 h1:Wxjda4M/BBQllegefXrY/9aq1fxBA8sI5M/lFU6tSWU=
+github.com/go-openapi/jsonreference v0.21.2/go.mod h1:pp3PEjIsJ9CZDGCNOyXIQxsNuroxm8FAJ/+quA0yKzQ=
 github.com/go-openapi/spec v0.22.0 h1:xT/EsX4frL3U09QviRIZXvkh80yibxQmtoEvyqug0Tw=
+github.com/go-openapi/spec v0.22.0/go.mod h1:K0FhKxkez8YNS94XzF8YKEMULbFrRw4m15i2YUht4L0=
 github.com/go-openapi/swag v0.19.15 h1:D2NRCBzS9/pEY3gP9Nl8aDqGUcPFrwG2p+CNFrLyrCM=
 github.com/go-openapi/swag/conv v0.25.1 h1:+9o8YUg6QuqqBM5X6rYL/p1dpWeZRhoIt9x7CCP+he0=
+github.com/go-openapi/swag/conv v0.25.1/go.mod h1:Z1mFEGPfyIKPu0806khI3zF+/EUXde+fdeksUl2NiDs=
 github.com/go-openapi/swag/jsonname v0.25.4 h1:bZH0+MsS03MbnwBXYhuTttMOqk+5KcQ9869Vye1bNHI=
+github.com/go-openapi/swag/jsonname v0.25.4/go.mod h1:GPVEk9CWVhNvWhZgrnvRA6utbAltopbKwDu8mXNUMag=
 github.com/go-openapi/swag/jsonutils v0.25.1 h1:AihLHaD0brrkJoMqEZOBNzTLnk81Kg9cWr+SPtxtgl8=
+github.com/go-openapi/swag/jsonutils v0.25.1/go.mod h1:JpEkAjxQXpiaHmRO04N1zE4qbUEg3b7Udll7AMGTNOo=
 github.com/go-openapi/swag/jsonutils/fixtures_test v0.25.1 h1:DSQGcdB6G0N9c/KhtpYc71PzzGEIc/fZ1no35x4/XBY=
+github.com/go-openapi/swag/jsonutils/fixtures_test v0.25.1/go.mod h1:kjmweouyPwRUEYMSrbAidoLMGeJ5p6zdHi9BgZiqmsg=
 github.com/go-openapi/swag/loading v0.25.1 h1:6OruqzjWoJyanZOim58iG2vj934TysYVptyaoXS24kw=
+github.com/go-openapi/swag/loading v0.25.1/go.mod h1:xoIe2EG32NOYYbqxvXgPzne989bWvSNoWoyQVWEZicc=
 github.com/go-openapi/swag/stringutils v0.25.1 h1:Xasqgjvk30eUe8VKdmyzKtjkVjeiXx1Iz0zDfMNpPbw=
+github.com/go-openapi/swag/stringutils v0.25.1/go.mod h1:JLdSAq5169HaiDUbTvArA2yQxmgn4D6h4A+4HqVvAYg=
 github.com/go-openapi/swag/typeutils v0.25.1 h1:rD/9HsEQieewNt6/k+JBwkxuAHktFtH3I3ysiFZqukA=
+github.com/go-openapi/swag/typeutils v0.25.1/go.mod h1:9McMC/oCdS4BKwk2shEB7x17P6HmMmA6dQRtAkSnNb8=
 github.com/go-openapi/swag/yamlutils v0.25.1 h1:mry5ez8joJwzvMbaTGLhw8pXUnhDK91oSJLDPF1bmGk=
+github.com/go-openapi/swag/yamlutils v0.25.1/go.mod h1:cm9ywbzncy3y6uPm/97ysW8+wZ09qsks+9RS8fLWKqg=
 github.com/go-openapi/testify/v2 v2.0.2 h1:X999g3jeLcoY8qctY/c/Z8iBHTbwLz7R2WXd6Ub6wls=
+github.com/go-openapi/testify/v2 v2.0.2/go.mod h1:HCPmvFFnheKK2BuwSA0TbbdxJ3I16pjwMkYkP4Ywn54=
 github.com/go-playground/assert/v2 v2.2.0 h1:JvknZsQTYeFEAhQwI4qEt9cyV5ONwRHC+lYKSsYSR8s=
 github.com/go-playground/assert/v2 v2.2.0/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
 github.com/go-playground/locales v0.14.1 h1:EWaQ/wswjilfKLTECiXz7Rh+3BjFhfDFKv/oXslEjJA=
@@ -202,6 +217,7 @@ github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0t
 github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/sergi/go-diff v1.4.0 h1:n/SP9D5ad1fORl+llWyN+D6qoUETXNZARKjyY2/KVCw=
+github.com/sergi/go-diff v1.4.0/go.mod h1:A0bzQcvG0E7Rwjx0REVgAGH58e96+X0MeOfepqsbeW4=
 github.com/sosodev/duration v1.3.1 h1:qtHBDMQ6lvMQsL15g4aopM4HEfOaYuhWBw3NPTtlqq4=
 github.com/sosodev/duration v1.3.1/go.mod h1:RQIBBX0+fMLc/D9+Jb/fwvVmo0eZvDDEERAikUR6SDg=
 github.com/spf13/cobra v1.10.2 h1:DMTTonx5m65Ic0GOoRY2c16WCbHxOOw6xxezuLaBpcU=
diff --git a/modernization_test.go b/modernization_test.go
new file mode 100644
index 0000000..2405717
--- /dev/null
+++ b/modernization_test.go
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+package api_test
+
+import (
+	"slices"
+	"testing"
+
+	api "forge.lthn.ai/core/go-api"
+)
+
+func TestEngine_GroupsIter(t *testing.T) {
+	e, _ := api.New()
+	g1 := &healthGroup{}
+	e.Register(g1)
+
+	var groups []api.RouteGroup
+	for g := range e.GroupsIter() {
+		groups = append(groups, g)
+	}
+
+	if len(groups) != 1 {
+		t.Fatalf("expected 1 group, got %d", len(groups))
+	}
+	if groups[0].Name() != "health-extra" {
+		t.Errorf("expected group name 'health-extra', got %q", groups[0].Name())
+	}
+}
+
+type streamGroupStub struct {
+	healthGroup
+	channels []string
+}
+
+func (s *streamGroupStub) Channels() []string { return s.channels }
+
+func TestEngine_ChannelsIter(t *testing.T) {
+	e, _ := api.New()
+	g1 := &streamGroupStub{channels: []string{"ch1", "ch2"}}
+	g2 := &streamGroupStub{channels: []string{"ch3"}}
+	e.Register(g1)
+	e.Register(g2)
+
+	var channels []string
+	for ch := range e.ChannelsIter() {
+		channels = append(channels, ch)
+	}
+
+	expected := []string{"ch1", "ch2", "ch3"}
+	if !slices.Equal(channels, expected) {
+		t.Fatalf("expected channels %v, got %v", expected, channels)
+	}
+}
+
+func TestToolBridge_Iterators(t *testing.T) {
+	b := api.NewToolBridge("/tools")
+	desc := api.ToolDescriptor{Name: "test", Group: "g1"}
+	b.Add(desc, nil)
+
+	// Test ToolsIter
+	var tools []api.ToolDescriptor
+	for t := range b.ToolsIter() {
+		tools = append(tools, t)
+	}
+	if len(tools) != 1 || tools[0].Name != "test" {
+		t.Errorf("ToolsIter failed, got %v", tools)
+	}
+
+	// Test DescribeIter
+	var descs []api.RouteDescription
+	for d := range b.DescribeIter() {
+		descs = append(descs, d)
+	}
+	if len(descs) != 1 || descs[0].Path != "/test" {
+		t.Errorf("DescribeIter failed, got %v", descs)
+	}
+}
+
+func TestCodegen_SupportedLanguagesIter(t *testing.T) {
+	var langs []string
+	for l := range api.SupportedLanguagesIter() {
+		langs = append(langs, l)
+	}
+
+	if !slices.Contains(langs, "go") {
+		t.Errorf("SupportedLanguagesIter missing 'go'")
+	}
+
+	// Should be sorted
+	if !slices.IsSorted(langs) {
+		t.Errorf("SupportedLanguagesIter should be sorted, got %v", langs)
+	}
+}
diff --git a/openapi_test.go b/openapi_test.go
index c4c58a7..e5107e7 100644
--- a/openapi_test.go
+++ b/openapi_test.go
@@ -20,16 +20,16 @@ type specStubGroup struct {
 	descs    []api.RouteDescription
 }
 
-func (s *specStubGroup) Name() string                        { return s.name }
-func (s *specStubGroup) BasePath() string                    { return s.basePath }
-func (s *specStubGroup) RegisterRoutes(rg *gin.RouterGroup)  {}
-func (s *specStubGroup) Describe() []api.RouteDescription    { return s.descs }
+func (s *specStubGroup) Name() string                       { return s.name }
+func (s *specStubGroup) BasePath() string                   { return s.basePath }
+func (s *specStubGroup) RegisterRoutes(rg *gin.RouterGroup) {}
+func (s *specStubGroup) Describe() []api.RouteDescription   { return s.descs }
 
 type plainStubGroup struct{}
 
-func (plainStubGroup) Name() string                        { return "plain" }
-func (plainStubGroup) BasePath() string                    { return "/plain" }
-func (plainStubGroup) RegisterRoutes(rg *gin.RouterGroup)  {}
+func (plainStubGroup) Name() string                       { return "plain" }
+func (plainStubGroup) BasePath() string                   { return "/plain" }
+func (plainStubGroup) RegisterRoutes(rg *gin.RouterGroup) {}
 
 // ── SpecBuilder tests ─────────────────────────────────────────────────────
 
diff --git a/secure_test.go b/secure_test.go
index efcdf75..781c017 100644
--- a/secure_test.go
+++ b/secure_test.go
@@ -101,9 +101,9 @@ func TestWithSecure_Good_AllHeadersPresent(t *testing.T) {
 
 	// Verify all security headers are present on a regular route.
 	checks := map[string]string{
-		"X-Frame-Options":           "DENY",
-		"X-Content-Type-Options":    "nosniff",
-		"Referrer-Policy":           "strict-origin-when-cross-origin",
+		"X-Frame-Options":        "DENY",
+		"X-Content-Type-Options": "nosniff",
+		"Referrer-Policy":        "strict-origin-when-cross-origin",
 	}
 
 	for header, want := range checks {
diff --git a/sse.go b/sse.go
index c3701c1..9adf7ee 100644
--- a/sse.go
+++ b/sse.go
@@ -143,4 +143,3 @@ func (b *SSEBroker) Drain() {
 		}
 	}
 }
-