A route may have its own listener: every request there is that route, paths unprefixed

Implemented-By: OpenCode session (model recorded in docs/implementer-log.md)

cmd/crossbar/main.go

@@ -11,6 +11,7 @@ import (
 	"net/http"
 	"os"
 	"os/signal"
+	"sort"
 	"syscall"
 	"time"
 
@@ -94,21 +95,56 @@ func run() error {
 	p := proxy.New(cfg, table, leases, lim, st, log)
 	p.SetWaker(waker)
 
-	var handler http.Handler = p
+	// Identity: gate the proxy on the route's peers when a backend is
-	if cfg.Identity != "off" {
+	// configured; off leaves the proxy unwrapped. The same checker gates each
+	// route's dedicated listener.
+	logIdentityMode(log, cfg.Identity)
+
 	var checker *identity.Checker
+	if cfg.Identity != "off" {
 		switch cfg.Identity {
 		case "tailscale":
 			checker = identity.NewChecker(identity.TailscaleResolver{})
 		default: // "header"
 			checker = identity.NewHeaderChecker()
 		}
+	}
+	var handler http.Handler = p
+	if checker != nil {
 		handler = identity.Middleware(checker, func(route string) ([]string, bool) {
 			rt, _, ok := cfg.Route(route)
 			return rt.Peers, ok
 		}, p)
 	}
 
+	// Routes with a dedicated listener each serve their own address, with every request there being
+	// that route and the path unprefixed. In sorted route order, one server each, the proxy's
+	// ForRoute handler wrapped in RouteMiddleware when identity is on. No admin mux on them.
+	type routeServer struct {
+		route string
+		srv   *http.Server
+	}
+	var routes []routeServer
+	listens := make([]string, 0, len(cfg.Routes))
+	for name := range cfg.Routes {
+		if cfg.Routes[name].Listen != "" {
+			listens = append(listens, name)
+		}
+	}
+	sort.Strings(listens)
+	for _, name := range listens {
+		rt := cfg.Routes[name]
+		var h http.Handler = p.ForRoute(name)
+		if checker != nil {
+			h = identity.RouteMiddleware(checker, rt.Peers, h)
+		}
+		routes = append(routes, routeServer{route: name, srv: &http.Server{
+			Addr:              rt.Listen,
+			Handler:           h,
+			ReadHeaderTimeout: 10 * time.Second,
+		}})
+	}
+
 	mux := http.NewServeMux()
 	mux.Handle("/_crossbar/", admin.Handler(cfg, table, leases, lim, st, hosts))
 	mux.Handle("/", handler)
@@ -173,22 +209,47 @@ func run() error {
 		ReadHeaderTimeout: 10 * time.Second,
 	}
 
-	serverErr := make(chan error, 1)
+	// Every listener shuts down together on ctx done; the first error other than a clean shutdown
+	// ends run and shuts the rest down.
+	servers := make([]*http.Server, 0, 1+len(routes))
+	servers = append(servers, srv)
+	for i := range routes {
+		servers = append(servers, routes[i].srv)
+	}
+	serverErr := make(chan error, len(servers))
+	start := func(s *http.Server, route string) {
 		go func() {
-		log.Info("listening", "addr", srv.Addr)
+			if route != "" {
-		serverErr <- srv.ListenAndServe()
+				log.Info("listening", "addr", s.Addr, "route", route)
+			} else {
+				log.Info("listening", "addr", s.Addr)
+			}
+			serverErr <- s.ListenAndServe()
 		}()
+	}
+	start(srv, "")
+	for _, rs := range routes {
+		start(rs.srv, rs.route)
+	}
 
 	select {
 	case <-ctx.Done():
 		log.Info("shutting down")
 		shutdownCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 		defer cancel()
-		return srv.Shutdown(shutdownCtx)
+		for _, s := range servers {
+			_ = s.Shutdown(shutdownCtx)
+		}
+		return nil
 	case err := <-serverErr:
 		if errors.Is(err, http.ErrServerClosed) {
 			return nil
 		}
+		shutdownCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+		for _, s := range servers {
+			_ = s.Shutdown(shutdownCtx)
+		}
 		return err
 	}
 }

docs/implementer-log.md

@@ -5,6 +5,7 @@ owner fills in the Model column. The reviewer adds findings under "Reviews" once
 
 | Task | Date | Status | Gate runs | First gate | Deviations | Notes | Model |
 |---|---|---|---|---|---|---|---|
+| v2.3/03-route-listeners | 2026-09-25 | done | 1 | pass | `cmd/crossbar/main.go` refactors the identity build so one `*identity.Checker` (nil when off) gates both the main proxy and every route's `RouteMiddleware` (task said "wrapped in RouteMiddleware when identity on"; the checker had to be shared, not rebuilt per server). `proxy.go` gains a shared `serve()` flow that both `ServeHTTP` and `ForRoute` converge on, so lease keying is identical whether a request hits the main proxy or a dedicated listener (required by `TestForRouteServesUnprefixedPaths` which asserts bm-a/bm-b share one bm lease). | Implemented `internal/config/route.go`: `Route.Listen` (`toml:"listen"`), `checkListen` validating in the order the task lists it — numeric port 1–65535, not on the template, not equal to the main listen, unique across routes (a second route in sorted-name order reports the clash with the earlier route's name). `internal/proxy/proxy.go`: `ForRoute(name)` returns 404 for an unknown route, 400 for a conflicting `X-Crossbar-Route`, 404 for any prefixed/admin/root path (so a dedicated listener never serves another route), else the shared serve with the path unprefixed. `internal/identity/middleware.go`: `RouteMiddleware` (fixed peers, no admin-path exemption, empty peers lets all through). `main.go`: per-route servers in sorted route order, shared shutdown on ctx done, first non-`ErrServerClosed` error ends run. All five given/protected files byte-identical; `make gate` → `gate: ok` first run, `make smoke` → `smoke: ok (stream spread 1004 ms)`. | ? |
 | v2.3/02-affinity-queue | 2026-09-25 | done | 1 | pass | `internal/proxy/proxy.go`'s slot (Acquire) path now releases on flush, not after `forward()`; the task only said Track must flush. | Implemented `internal/config/route.go` (Route with `Affinity`/`Queue *bool`, `PerRoute()`, `Queues()`; affinity validation `""`/`conversation`/`route`, error names `routes.<name>.affinity`; moved `checkRoutes`/`routeName`). `config.go`: one-line call to `checkRoutes`. `internal/limiter/limiter.go`: `Track(host, model) func()` increments inflight, idempotent release hands a slot to a waiter only when `inflight <= parallel`. `proxy.go`: `leaseFP = ""` in the lease key when `routeCfg.PerRoute()` (main Acquire and wake call) so `route`/template routes share one lease; `serveLeased` uses `p.lim.Track` when `routeCfg.Queues()` is false, else `Acquire`. `forward.go`: `forward()` gained a `release func()` param; `statusRecorder.onFlush` field with `Flush()` calling `onFlush()` before the underlying flush. This was required to fix a scheduling race caught by the given `TestQueueFalseNeitherHoldsNorRefuse`: the release originally ran after `forward()` returned, but `forward()` writes the SQLite row after the response bytes are flushed, so the loopback client finished `Do()` before `release()` ran and the test's non-polling `InFlight == 0` check fired on a still-3 inflight. Releasing when the response flushes makes inflight zero before the caller observes it. Both given tests byte-identical; `make gate` → `gate: ok`, `make smoke` → `smoke: ok (stream spread 1007 ms)`. | ? **Owner review:** the release-on-flush was reverted — it let every streaming request give back its slot at its first byte, so the limiter stopped limiting generation; the race it worked around was in the owner's given test (`InFlight == 0` checked before the deferred release), now fixed, with `TestLoadIsHeldForTheWholeStream` added. Session ended on a refused `/tmp` write while committing; owner committed. |
 | v2.3/01-control-plane | 2026-09-25 | done | 1 | pass | none | New `internal/proxy/control.go`: `isControlCall` (GET/HEAD on any allowed path, or POST to exactly `/tokenize`/`/v1/chat/completions/control`) and `resolveModel` (body `model` → `?model=` → route `default_model`). `proxy.go`: `allowedPath` admits `/slots` and `/tokenize`; the default_model-only fallback replaced by `resolveModel`; `isControlCall` computed once in `ServeHTTP`; `serveLeased` forwards a control call straight to `forward` (no limiter acquire, no context guard, no row); `wakeOnErrNoHost` threads `isControlCall(r.Method, rest)` through. `forward.go` gained a trailing `control bool` that skips `writeRecord` in both the normal and recover paths and logs at Debug instead of Info. Both given tests byte-identical; `make gate` → `gate: ok` on the first run. | ? |
 | v2.2/02-broadcasts | 2026-09-25 | done | 1 | pass | The Wake struct and checkWake live in `internal/config/identity.go` (added in task 04), not `config.go`, so I edited `identity.go` rather than `config.go`; `wake.go` logs a broadcast that fails to resolve/send before continuing (task rule 2 allows "logged or ignored"). | Added `Broadcasts` to `Wake` and `Wake.Addresses()` (Broadcast then Broadcasts, never empty for a parsed config); `checkWake` errors on both-set → `.broadcasts`, neither-or-empty-list → `.broadcast`, and a non-`host:port` entry → `.broadcasts`; `Target` gains `Broadcasts` and `Wake`/`sendAll` send to Broadcast then each Broadcasts in order, logging/past a failure and returning false only when no address could be sent; `main.go` fills `Target.Broadcasts` from `Wake.Addresses()` and leaves `Target.Broadcast` empty so `sendAll` does not double-send. Given `broadcasts_test.go` and `config_v22_test.go` byte-identical, v2 `wake_test.go`/`config_v2_test.go` untouched and green; `make gate` → `gate: ok` first run. | ? |

example.toml

@@ -31,3 +31,13 @@ default_model = "ornith-1.5-35b-a3b"
 [routes.hermes-x]
 hosts = ["beta", "alpha"]
 # peers = ["talos"]                    # v2: with identity = "tailscale", only these tailnet nodes may use the route
+
+# v2.3: a client that manages its own llama-server slot (it pins id_slot, polls /slots, steers a
+# running completion through /v1/chat/completions/control) and cannot put a route in the path.
+# The route gets its own port; every request there is this route and the path goes upstream as is.
+[routes.boxmaker-a]
+hosts         = ["beta", "alpha"]
+default_model = "ornith-1.5-35b-a3b"
+listen        = "127.0.0.1:17801"      # a tailnet address in production; never the main listen address
+affinity      = "route"                # one lease for the whole route, not one per conversation
+queue         = false                  # counted as load but never held or refused: the server's own slot queue does that

internal/config/listen_test.go

@@ -0,0 +1,54 @@
+package config_test
+
+// v2.3 task 03: a concrete route may own a dedicated listener. Every request that arrives on it is
+// that route, with the upstream path unprefixed, for clients that cannot put a route in the path
+// or a header (Boxmaker's inferproxy rewrites nothing).
+
+import (
+	"strings"
+	"testing"
+
+	"git.wntrmute.dev/kyle/crossbar/internal/config"
+)
+
+const listenBase = `
+listen = "127.0.0.1:7777"
+[hosts.a]
+base_url = "http://a:1"
+models = { "m" = { } }
+[routes.bm-a]
+hosts = ["a"]
+listen = "127.0.0.1:7801"
+[routes.bm-b]
+hosts = ["a"]
+listen = "127.0.0.1:7802"
+[routes.plain]
+hosts = ["a"]
+`
+
+func TestRouteListen(t *testing.T) {
+	c, err := config.Parse(strings.NewReader(listenBase))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for route, want := range map[string]string{"bm-a": "127.0.0.1:7801", "bm-b": "127.0.0.1:7802", "plain": ""} {
+		if got := c.Routes[route].Listen; got != want {
+			t.Errorf("%s listen = %q, want %q", route, got, want)
+		}
+	}
+}
+
+func TestRouteListenRejected(t *testing.T) {
+	for _, tc := range []struct{ name, text, want string }{
+		{"not host:port", strings.Replace(listenBase, `"127.0.0.1:7801"`, `"7801"`, 1), "routes.bm-a.listen"},
+		{"bad port", strings.Replace(listenBase, `"127.0.0.1:7801"`, `"127.0.0.1:http"`, 1), "routes.bm-a.listen"},
+		{"port zero", strings.Replace(listenBase, `"127.0.0.1:7801"`, `"127.0.0.1:0"`, 1), "routes.bm-a.listen"},
+		{"same as another route", strings.Replace(listenBase, `"127.0.0.1:7802"`, `"127.0.0.1:7801"`, 1), "listen"},
+		{"same as the main listener", strings.Replace(listenBase, `"127.0.0.1:7801"`, `"127.0.0.1:7777"`, 1), "routes.bm-a.listen"},
+		{"on a template", listenBase + "[routes.\"t-*\"]\nhosts = [\"a\"]\nlisten = \"127.0.0.1:7803\"\n", "t-*"},
+	} {
+		if _, err := config.Parse(strings.NewReader(tc.text)); err == nil || !strings.Contains(err.Error(), tc.want) {
+			t.Errorf("%s: err %v, want one containing %q", tc.name, err, tc.want)
+		}
+	}
+}

internal/config/route.go

@@ -2,8 +2,10 @@ package config
 
 import (
 	"fmt"
+	"net"
 	"regexp"
 	"sort"
+	"strconv"
 	"strings"
 )
 
@@ -22,6 +24,7 @@ type Route struct {
 	Peers        []string `toml:"peers"`
 	Affinity     string   `toml:"affinity"` // "" or "conversation" (the default), or "route"
 	Queue        *bool    `toml:"queue"`    // nil means true
+	Listen       string   `toml:"listen"`   // "" = none; else host:port of the route's own listener
 }
 
 // PerRoute reports affinity = "route": every request on the route (chat or control) shares one
@@ -80,6 +83,9 @@ func (c *Config) checkRoutes(peersDefined map[string]bool, identityDefined bool)
 		names = append(names, name)
 	}
 	sort.Strings(names)
+	// A route's own listener address, keyed for the uniqueness check: the value is the
+	// route that first claimed it, so the second route in sorted order reports the miss.
+	seenListen := make(map[string]string, len(c.Routes))
 	for _, name := range names {
 		r := c.Routes[name]
 
@@ -124,6 +130,39 @@ func (c *Config) checkRoutes(peersDefined map[string]bool, identityDefined bool)
 		if e := checkPeers(name, r.Peers, peersDefined[name], identityDefined, c.Identity); e != nil {
 			return e
 		}
+
+		if e := checkListen(name, r.Listen, c.Listen, seenListen); e != nil {
+			return e
+		}
 	}
 	return nil
 }
+
+// checkListen validates one route's own listener. The rules, in order, each naming the key
+// routes.<name>.listen: the value must split into host and a numeric port 1-65535, it must not be on
+// a template route, it must not be the top-level listen, and it must be unique across routes (the
+// second route in sorted name order reports the clash and the other route's name).
+func checkListen(name, listen, mainListen string, seenListen map[string]string) *Error {
+	if listen == "" {
+		return nil
+	}
+	_, port, err := net.SplitHostPort(listen)
+	if err != nil {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "must be host:port"}
+	}
+	n, err := strconv.Atoi(port)
+	if err != nil || n < 1 || n > 65535 {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "port must be 1-65535"}
+	}
+	if templateName.MatchString(name) {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "a template route cannot have its own listener"}
+	}
+	if listen == mainListen {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: "cannot be the main listen address"}
+	}
+	if other, dup := seenListen[listen]; dup {
+		return &Error{Field: fmt.Sprintf("routes.%s.listen", name), Msg: fmt.Sprintf("already used by route %s", other)}
+	}
+	seenListen[listen] = name
+	return nil
+}

internal/identity/middleware.go

@@ -45,6 +45,21 @@ func Middleware(c *Checker, peersFor func(route string) ([]string, bool), next h
 	})
 }
 
+// RouteMiddleware gates every request on a fixed set of peers, whatever path or X-Crossbar-Route
+// header it carries: on a route's dedicated listener the route is fixed, so the gate is that route's
+// peers for every request. There is no admin-path exemption — there is no admin on a route listener.
+// Empty peers lets everyone through, as for Middleware.
+func RouteMiddleware(c *Checker, peers []string, next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ctx := WithHeaderPeer(r.Context(), r.Header.Get(peerHeader))
+		if err := c.Allow(ctx, peers, r.RemoteAddr); err != nil {
+			writeForbidden(w)
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
 // writeForbidden answers the JSON 403 the tests and callers expect.
 func writeForbidden(w http.ResponseWriter) {
 	w.Header().Set("Content-Type", "application/json")

internal/identity/route_middleware_test.go

@@ -0,0 +1,47 @@
+package identity_test
+
+// v2.3 task 03: on a route's dedicated listener the route is fixed, so the gate is that route's
+// peers for every request, whatever path or X-Crossbar-Route header the caller sends.
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"git.wntrmute.dev/kyle/crossbar/internal/identity"
+)
+
+func TestRouteMiddleware(t *testing.T) {
+	inner := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { w.WriteHeader(204) })
+	checker := identity.NewChecker(fakeResolver{"100.64.0.5": "talos", "100.64.0.9": "titan"})
+	locked := identity.RouteMiddleware(checker, []string{"talos"}, inner)
+	open := identity.RouteMiddleware(checker, nil, inner)
+	for _, tc := range []struct {
+		name      string
+		h         http.Handler
+		path, hdr string
+		addr      string
+		want      int
+	}{
+		{"right peer", locked, "/v1/chat/completions", "", "100.64.0.5:5", 204},
+		{"wrong peer", locked, "/v1/chat/completions", "", "100.64.0.9:5", 403},
+		{"not a peer", locked, "/slots", "", "203.0.113.1:5", 403},
+		{"a path that looks like an open route is still this route", locked, "/open/v1/models", "", "100.64.0.9:5", 403},
+		{"a header naming another route does not change the gate", locked, "/v1/models", "open", "100.64.0.9:5", 403},
+		{"admin-looking path is gated too (no admin on this listener)", locked, "/_crossbar/hosts", "", "100.64.0.9:5", 403},
+		{"open route, anyone", open, "/v1/models", "", "203.0.113.1:5", 204},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			req := httptest.NewRequest(http.MethodGet, tc.path, nil)
+			req.RemoteAddr = tc.addr
+			if tc.hdr != "" {
+				req.Header.Set("X-Crossbar-Route", tc.hdr)
+			}
+			rec := httptest.NewRecorder()
+			tc.h.ServeHTTP(rec, req)
+			if rec.Code != tc.want {
+				t.Errorf("%s = %d, want %d (%s)", tc.path, rec.Code, tc.want, rec.Body.String())
+			}
+		})
+	}
+}

internal/proxy/listener_test.go

@@ -0,0 +1,112 @@
+package proxy_test
+
+// v2.3 task 03: Handler.ForRoute serves one route with unprefixed paths, for a route's dedicated
+// listener.
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"git.wntrmute.dev/kyle/crossbar/internal/proxy"
+)
+
+// dedicated serves r's route on its own test server, sharing r's health, leases, limiter and
+// store, as main does for a route with listen set.
+func dedicated(t *testing.T, r *rig, route string) *httptest.Server {
+	p := proxy.New(r.cfg, r.health, r.leases, r.lim, r.store, nil)
+	srv := httptest.NewServer(p.ForRoute(route))
+	t.Cleanup(srv.Close)
+	return srv
+}
+
+func call(t *testing.T, method, url, body string, hdr ...string) (*http.Response, string) {
+	t.Helper()
+	var req *http.Request
+	if body != "" {
+		req, _ = http.NewRequest(method, url, strings.NewReader(body))
+		req.Header.Set("Content-Type", "application/json")
+	} else {
+		req, _ = http.NewRequest(method, url, nil)
+	}
+	for i := 0; i+1 < len(hdr); i += 2 {
+		req.Header.Set(hdr[i], hdr[i+1])
+	}
+	resp, err := controlClient.Do(req)
+	if err != nil {
+		t.Fatalf("%s %s: %v", method, url, err)
+	}
+	return resp, drain(resp)
+}
+
+func TestForRouteServesUnprefixedPaths(t *testing.T) {
+	alpha, beta := newUpstream(t, "alpha"), newUpstream(t, "beta")
+	r := newRig(t, affinityHosts, alpha, beta)
+	srv := dedicated(t, r, "bm")
+
+	resp, body := call(t, http.MethodPost, srv.URL+"/v1/chat/completions", conversation(1, 1))
+	if resp.StatusCode != 200 {
+		t.Fatalf("chat on the dedicated listener: %d %s", resp.StatusCode, body)
+	}
+	host := resp.Header.Get("X-Crossbar-Host")
+	up := map[string]*upstream{"alpha": alpha, "beta": beta}[host]
+	if up == nil || up.lastReq().path != "/v1/chat/completions" {
+		t.Fatalf("upstream %q saw %+v, want /v1/chat/completions unchanged", host, up.lastReq())
+	}
+	resp, _ = call(t, http.MethodGet, srv.URL+"/slots?model=shared", "")
+	if resp.StatusCode != 200 || resp.Header.Get("X-Crossbar-Host") != host || up.lastReq().path != "/slots?model=shared" {
+		t.Errorf("/slots: %d on %q (last %+v), want 200 on %q", resp.StatusCode, resp.Header.Get("X-Crossbar-Host"), up.lastReq(), host)
+	}
+	resp, _ = call(t, http.MethodPost, srv.URL+"/v1/chat/completions/control", `{"id":"chatcmpl-1","action":"reasoning_end","model":"shared"}`)
+	if resp.StatusCode != 200 || resp.Header.Get("X-Crossbar-Host") != host {
+		t.Errorf("/control: %d on %q, want 200 on %q", resp.StatusCode, resp.Header.Get("X-Crossbar-Host"), host)
+	}
+	// The chat is accounted to the route the listener serves.
+	waitUntil(t, func() bool { return r.rows("bm") == 1 })
+	// The same route through the main listener shares the lease: same host.
+	resp = r.do(http.MethodPost, "/bm/v1/chat/completions", conversation(2, 1))
+	drain(resp)
+	if resp.Header.Get("X-Crossbar-Host") != host {
+		t.Errorf("main listener /bm went to %q, dedicated to %q; one route, one lease", resp.Header.Get("X-Crossbar-Host"), host)
+	}
+}
+
+func TestForRouteRefusals(t *testing.T) {
+	alpha, beta := newUpstream(t, "alpha"), newUpstream(t, "beta")
+	r := newRig(t, affinityHosts, alpha, beta)
+	srv := dedicated(t, r, "bm")
+	for _, tc := range []struct {
+		name, method, path string
+		hdr                []string
+		want               int
+		msg                string
+	}{
+		{"a prefixed path is not stripped", http.MethodGet, "/bm/v1/models", nil, 404, "not found"},
+		{"no admin here", http.MethodGet, "/_crossbar/hosts", nil, 404, "not found"},
+		{"root", http.MethodGet, "/", nil, 404, "not found"},
+		{"header naming another route", http.MethodGet, "/v1/models", []string{"X-Crossbar-Route", "r"}, 400, "conflicting route"},
+	} {
+		resp, body := call(t, tc.method, srv.URL+tc.path, "", tc.hdr...)
+		var e map[string]string
+		if resp.StatusCode != tc.want || json.Unmarshal([]byte(body), &e) != nil || e["error"] != tc.msg {
+			t.Errorf("%s: %d %s, want %d %q", tc.name, resp.StatusCode, body, tc.want, tc.msg)
+		}
+	}
+	// A header naming this same route is harmless.
+	resp, body := call(t, http.MethodGet, srv.URL+"/v1/models", "", "X-Crossbar-Route", "bm")
+	if resp.StatusCode != 200 {
+		t.Errorf("header naming the listener's own route: %d %s, want 200", resp.StatusCode, body)
+	}
+}
+
+func TestForRouteUnknownRoute(t *testing.T) {
+	alpha, beta := newUpstream(t, "alpha"), newUpstream(t, "beta")
+	r := newRig(t, affinityHosts, alpha, beta)
+	srv := dedicated(t, r, "nope")
+	resp, body := call(t, http.MethodGet, srv.URL+"/v1/models", "")
+	if resp.StatusCode != 404 || !strings.Contains(body, "unknown route") {
+		t.Errorf("ForRoute(unknown): %d %s, want 404 unknown route", resp.StatusCode, body)
+	}
+}

internal/proxy/proxy.go

@@ -198,15 +198,45 @@ func peekModel(r *http.Request) (string, []byte, error) {
 	return req.Model, body, nil
 }
 
-// ServeHTTP routes, fingerprints, leases a host, queues per (host, model), forwards with streaming,
+// ServeHTTP routes, then serves the request over the shared flow below: fingerprint, lease a host,
-// tees the response for usage/timings, and records one accounting row. Every error answer is JSON
+// queue per (host, model), forward with streaming, tee the response for usage/timings, and record
-// {"error":"…"}.
+// one accounting row. Every error answer is JSON {"error":"…"}.
 func (p *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	route, rest, code, msg := p.route(r)
 	if code != 0 {
 		p.writeError(w, code, msg)
 		return
 	}
+	p.serve(w, r, route, rest)
+}
+
+// ForRoute serves route alone, for its dedicated listener: every request there is this route, the
+// whole path passed upstream as it is (no route segment is taken from it). A request from an unknown
+// route is 404; a different X-Crossbar-Route header is a 400 (an equal one is ignored); a prefixed
+// path or a path outside the allowed set is 404. Then it runs the same serve flow as ServeHTTP.
+func (p *Handler) ForRoute(route string) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if _, _, ok := p.cfg.Route(route); !ok {
+			p.writeError(w, http.StatusNotFound, "unknown route")
+			return
+		}
+		if hdr := r.Header.Get(RouteHeader); hdr != "" && hdr != route {
+			p.writeError(w, http.StatusBadRequest, "conflicting route")
+			return
+		}
+		rest := r.URL.Path
+		if !allowedPath(rest) {
+			p.writeError(w, http.StatusNotFound, "not found")
+			return
+		}
+		p.serve(w, r, route, rest)
+	})
+}
+
+// serve fingerprints, leases a host, queues per (host, model), forwards with streaming, tees the
+// response for usage/timings, and records one accounting row. Both ServeHTTP and ForRoute reach this
+// after they have settled the route and the upstream path (rest).
+func (p *Handler) serve(w http.ResponseWriter, r *http.Request, route, rest string) {
 	routeCfg, _, _ := p.cfg.Route(route)
 	isControl := isControlCall(r.Method, rest)
 

tools/smoke.sh

@@ -1,5 +1,6 @@
 #!/bin/sh
-# Smoke run (v2): everything v1 checked, plus the context guard, wake-on-LAN and identity gating.
+# Smoke run (v2.3): everything v1 checked, plus the context guard, wake-on-LAN, identity gating and
+# a route's dedicated listener.
 # Prints "smoke: ok" or fails with the crossbar log.
 set -eu
 cd "$(dirname "$0")/.."
@@ -57,4 +58,14 @@ sleep 1
 curl -s "$base/_crossbar/usage?by=host" | grep -q '"cached_tokens":[1-9]' || fail "usage has no cached tokens"
 curl -s "$base/_crossbar/metrics" | grep -q 'crossbar_requests_total{route="hermes-x",host="beta",status="403"}' && fail "403s are refused before a lease and must not be counted as requests"
 curl -s "$base/_crossbar/metrics" | grep -q 'crossbar_host_healthy{host="beta"} 1' || fail "metrics missing beta health"
+# 6. v2.3: boxmaker-a has its own listener. Paths are unprefixed, the chat and a control call land
+#    on the same host (affinity = "route"), and the admin API is not served there.
+lb=http://127.0.0.1:17801
+h1=$(hdrs -X POST -H 'Content-Type: application/json' -d "$(conv C)" "$lb/v1/chat/completions")
+h2=$(hdrs "$lb/props?model=ornith-1.5-35b-a3b")
+case "$h1" in 200*) ;; *) fail "chat on the dedicated listener should be 200, got '$h1'";; esac
+[ "$(echo "$h1" | cut -d' ' -f2)" = "$(echo "$h2" | cut -d' ' -f2)" ] || fail "chat went to '$h1', /props to '$h2': one route, one host"
+h=$(curl -s -o /dev/null -w '%{http_code}' "$lb/_crossbar/hosts"); [ "$h" = "404" ] || fail "admin must not be served on a dedicated listener, got $h"
+h=$(curl -s -o /dev/null -w '%{http_code}' "$lb/boxmaker-a/v1/models"); [ "$h" = "404" ] || fail "a prefixed path on the dedicated listener should be 404, got $h"
+
 echo "smoke: ok (stream spread $((lastms - firstms)) ms)"