diff --git a/pkg/server/handlers_backends.go b/pkg/server/handlers_backends.go
index 390ecb0..a60c6ce 100644
--- a/pkg/server/handlers_backends.go
+++ b/pkg/server/handlers_backends.go
@@ -66,17 +66,16 @@ func (h *Handler) LlamaCppUIProxy() http.HandlerFunc {
 			return
 		}
 
-		proxy, err := inst.GetProxy()
-		if err != nil {
-			writeError(w, http.StatusInternalServerError, "failed to get proxy", err.Error())
-			return
-		}
-
 		if !inst.IsRemote() {
 			h.stripLlamaCppPrefix(r, inst.Name)
 		}
 
-		proxy.ServeHTTP(w, r)
+		// Use instance's ServeHTTP which tracks inflight requests and handles shutting down state
+		err = inst.ServeHTTP(w, r)
+		if err != nil {
+			// Error is already handled in ServeHTTP (response written)
+			return
+		}
 	}
 }
 
@@ -118,17 +117,16 @@ func (h *Handler) LlamaCppProxy() http.HandlerFunc {
 			}
 		}
 
-		proxy, err := inst.GetProxy()
-		if err != nil {
-			writeError(w, http.StatusInternalServerError, "failed to get proxy", err.Error())
-			return
-		}
-
 		if !inst.IsRemote() {
 			h.stripLlamaCppPrefix(r, inst.Name)
 		}
 
-		proxy.ServeHTTP(w, r)
+		// Use instance's ServeHTTP which tracks inflight requests and handles shutting down state
+		err = inst.ServeHTTP(w, r)
+		if err != nil {
+			// Error is already handled in ServeHTTP (response written)
+			return
+		}
 	}
 }
 
diff --git a/pkg/server/handlers_instances.go b/pkg/server/handlers_instances.go
index 0480f22..43bed3e 100644
--- a/pkg/server/handlers_instances.go
+++ b/pkg/server/handlers_instances.go
@@ -332,12 +332,6 @@ func (h *Handler) InstanceProxy() http.HandlerFunc {
 			return
 		}
 
-		proxy, err := inst.GetProxy()
-		if err != nil {
-			writeError(w, http.StatusInternalServerError, "proxy_failed", "Failed to get proxy: "+err.Error())
-			return
-		}
-
 		if !inst.IsRemote() {
 			// Strip the "/api/v1/instances/<name>/proxy" prefix from the request URL
 			prefix := fmt.Sprintf("/api/v1/instances/%s/proxy", inst.Name)
@@ -348,6 +342,11 @@ func (h *Handler) InstanceProxy() http.HandlerFunc {
 		r.Header.Set("X-Forwarded-Host", r.Header.Get("Host"))
 		r.Header.Set("X-Forwarded-Proto", "http")
 
-		proxy.ServeHTTP(w, r)
+		// Use instance's ServeHTTP which tracks inflight requests and handles shutting down state
+		err = inst.ServeHTTP(w, r)
+		if err != nil {
+			// Error is already handled in ServeHTTP (response written)
+			return
+		}
 	}
 }
diff --git a/pkg/server/handlers_openai.go b/pkg/server/handlers_openai.go
index d221200..0937e6a 100644
--- a/pkg/server/handlers_openai.go
+++ b/pkg/server/handlers_openai.go
@@ -114,16 +114,15 @@ func (h *Handler) OpenAIProxy() http.HandlerFunc {
 			}
 		}
 
-		proxy, err := inst.GetProxy()
-		if err != nil {
-			writeError(w, http.StatusInternalServerError, "proxy_failed", err.Error())
-			return
-		}
-
 		// Recreate the request body from the bytes we read
 		r.Body = io.NopCloser(bytes.NewReader(bodyBytes))
 		r.ContentLength = int64(len(bodyBytes))
 
-		proxy.ServeHTTP(w, r)
+		// Use instance's ServeHTTP which tracks inflight requests and handles shutting down state
+		err = inst.ServeHTTP(w, r)
+		if err != nil {
+			// Error is already handled in ServeHTTP (response written)
+			return
+		}
 	}
 }