diff --git a/cmd/sdrd/http_handlers.go b/cmd/sdrd/http_handlers.go
index 19a1338..2ed3f12 100644
--- a/cmd/sdrd/http_handlers.go
+++ b/cmd/sdrd/http_handlers.go
@@ -39,6 +39,12 @@ func registerAPIHandlers(mux *http.ServeMux, cfgPath string, cfgManager *runtime
 				http.Error(w, err.Error(), http.StatusBadRequest)
 				return
 			}
+			if update.Pipeline != nil && update.Pipeline.Profile != nil {
+				if prof, ok := pipeline.ResolveProfile(next, *update.Pipeline.Profile); ok {
+					pipeline.MergeProfile(&next, prof)
+					cfgManager.Replace(next)
+				}
+			}
 			sourceChanged := prev.CenterHz != next.CenterHz || prev.SampleRate != next.SampleRate || prev.GainDb != next.GainDb || prev.AGC != next.AGC || prev.TunerBwKHz != next.TunerBwKHz
 			if sourceChanged {
 				if err := srcMgr.ApplyConfig(next); err != nil {
diff --git a/internal/config/config_test.go b/internal/config/config_test.go
index e7b28e1..0218fe1 100644
--- a/internal/config/config_test.go
+++ b/internal/config/config_test.go
@@ -45,3 +45,20 @@ func TestLoadConfig(t *testing.T) {
 		t.Fatalf("event path default not applied")
 	}
 }
+
+func TestProfileDefaultsPresent(t *testing.T) {
+	cfg := Default()
+	if len(cfg.Profiles) < 2 {
+		t.Fatalf("expected built-in profiles")
+	}
+	found := false
+	for _, p := range cfg.Profiles {
+		if p.Name == "wideband-balanced" {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Fatalf("missing wideband-balanced profile")
+	}
+}
diff --git a/internal/pipeline/profile.go b/internal/pipeline/profile.go
new file mode 100644
index 0000000..e4e9ce0
--- /dev/null
+++ b/internal/pipeline/profile.go
@@ -0,0 +1,36 @@
+package pipeline
+
+import "sdr-wideband-suite/internal/config"
+
+func ResolveProfile(cfg config.Config, name string) (config.ProfileConfig, bool) {
+	for _, p := range cfg.Profiles {
+		if p.Name == name {
+			return p, true
+		}
+	}
+	return config.ProfileConfig{}, false
+}
+
+func MergeProfile(cfg *config.Config, profile config.ProfileConfig) {
+	if cfg == nil {
+		return
+	}
+	if profile.Pipeline != nil {
+		cfg.Pipeline = *profile.Pipeline
+	}
+	if profile.Surveillance != nil {
+		cfg.Surveillance = *profile.Surveillance
+	}
+	if profile.Refinement != nil {
+		cfg.Refinement = *profile.Refinement
+	}
+	if profile.Resources != nil {
+		cfg.Resources = *profile.Resources
+	}
+	if cfg.Surveillance.AnalysisFFTSize > 0 {
+		cfg.FFTSize = cfg.Surveillance.AnalysisFFTSize
+	}
+	if cfg.Surveillance.FrameRate > 0 {
+		cfg.FrameRate = cfg.Surveillance.FrameRate
+	}
+}
diff --git a/internal/pipeline/profile_test.go b/internal/pipeline/profile_test.go
new file mode 100644
index 0000000..f121ad9
--- /dev/null
+++ b/internal/pipeline/profile_test.go
@@ -0,0 +1,33 @@
+package pipeline
+
+import (
+	"testing"
+
+	"sdr-wideband-suite/internal/config"
+)
+
+func TestResolveAndMergeProfile(t *testing.T) {
+	cfg := config.Default()
+	cfg.Profiles = append(cfg.Profiles, config.ProfileConfig{
+		Name:        "custom-test",
+		Description: "test profile",
+		Pipeline: &config.PipelineConfig{Mode: "custom", Goals: config.PipelineGoalConfig{Intent: "custom-intent", MonitorSpanHz: 12.5e6}},
+		Surveillance: &config.SurveillanceConfig{AnalysisFFTSize: 16384, FrameRate: 8, Strategy: "single-resolution"},
+		Refinement: &config.RefinementConfig{Enabled: true, MaxConcurrent: 20, MinCandidateSNRDb: 4},
+		Resources: &config.ResourceConfig{PreferGPU: true, MaxRefinementJobs: 20, MaxRecordingStreams: 32},
+	})
+	p, ok := ResolveProfile(cfg, "custom-test")
+	if !ok {
+		t.Fatalf("expected profile")
+	}
+	MergeProfile(&cfg, p)
+	if cfg.Pipeline.Mode != "custom" || cfg.Pipeline.Goals.Intent != "custom-intent" {
+		t.Fatalf("pipeline not merged: %+v", cfg.Pipeline)
+	}
+	if cfg.FFTSize != 16384 || cfg.FrameRate != 8 {
+		t.Fatalf("surveillance not merged into legacy fields: fft=%d fps=%d", cfg.FFTSize, cfg.FrameRate)
+	}
+	if cfg.Resources.MaxRefinementJobs != 20 {
+		t.Fatalf("resources not merged: %+v", cfg.Resources)
+	}
+}
diff --git a/internal/runtime/runtime.go b/internal/runtime/runtime.go
index 8cb5f2e..8af9d9e 100644
--- a/internal/runtime/runtime.go
+++ b/internal/runtime/runtime.go
@@ -10,7 +10,8 @@ import (
 )
 
 type PipelineUpdate struct {
-	Mode *string `json:"mode"`
+	Mode    *string `json:"mode"`
+	Profile *string `json:"profile"`
 }
 
 type SurveillanceUpdate struct {
diff --git a/internal/runtime/runtime_test.go b/internal/runtime/runtime_test.go
index 2bc5171..4660d22 100644
--- a/internal/runtime/runtime_test.go
+++ b/internal/runtime/runtime_test.go
@@ -23,6 +23,7 @@ func TestApplyConfigUpdate(t *testing.T) {
 	cfarScale := 5.5
 
 	mode := "wideband-balanced"
+	profile := "wideband-balanced"
 	survFPS := 12
 	maxRefJobs := 24
 	updated, err := mgr.ApplyConfig(ConfigUpdate{
@@ -30,7 +31,7 @@ func TestApplyConfigUpdate(t *testing.T) {
 		SampleRate: &sampleRate,
 		FFTSize:    &fftSize,
 		TunerBwKHz: &bw,
-		Pipeline:   &PipelineUpdate{Mode: &mode},
+		Pipeline:   &PipelineUpdate{Mode: &mode, Profile: &profile},
 		Surveillance: &SurveillanceUpdate{FrameRate: &survFPS},
 		Resources: &ResourcesUpdate{MaxRefinementJobs: &maxRefJobs},
 		Detector: &DetectorUpdate{