Add the Rakestrawhome built-in backend

internal/backend/registry.go

@@ -18,12 +18,20 @@ const (
 	// OpenRouterID is the reserved ID of Promptkit's built-in OpenRouter
 	// backend.
 	OpenRouterID = "openrouter"
+	// RakestrawHomeID is the reserved ID of Promptkit's built-in Rakestrawhome
+	// backend.
+	RakestrawHomeID = "rakestrawhome"
 
 	openRouterEndpoint  = "https://openrouter.ai/api/v1"
 	openRouterAPIKeyEnv = "OPENROUTER_API_KEY"
 
 	openRouterConcurrencyLimit = 16
-	defaultQueueCapacity       = 1024
+
+	rakestrawHomeEndpoint  = "https://inference.ai.rakestrawhome.com/v1"
+	rakestrawHomeAPIKeyEnv = "RAKESTRAWHOME_INFERENCE_API_KEY"
+
+	rakestrawHomeConcurrencyLimit = 4
+	defaultQueueCapacity          = 1024
 )
 
 // ErrBackendNotFound identifies a registry lookup for an unknown backend ID.
@@ -36,20 +44,16 @@ type Registry struct {
 	backends map[string]domain.Backend
 }
 
-// NewRegistry constructs a registry containing the built-in OpenRouter
-// definition followed by the supplied additions. Every ID must be unique.
+// NewRegistry constructs a registry containing the built-in definitions
+// followed by the supplied additions. Every ID must be unique.
 func NewRegistry(additions []domain.Backend) (*Registry, error) {
+	builtIns := builtInBackends()
 	registry := &Registry{
-		backends: make(map[string]domain.Backend, len(additions)+1),
+		backends: make(map[string]domain.Backend, len(builtIns)+len(additions)),
 	}
 
-	definitions := make([]domain.Backend, 0, len(additions)+1)
-	definitions = append(definitions, domain.Backend{
-		ID:               OpenRouterID,
-		Endpoint:         openRouterEndpoint,
-		APIKeyEnv:        openRouterAPIKeyEnv,
-		ConcurrencyLimit: openRouterConcurrencyLimit,
-	})
+	definitions := make([]domain.Backend, 0, len(builtIns)+len(additions))
+	definitions = append(definitions, builtIns...)
 	definitions = append(definitions, additions...)
 
 	for _, definition := range definitions {
@@ -71,6 +75,23 @@ func NewRegistry(additions []domain.Backend) (*Registry, error) {
 	return registry, nil
 }
 
+func builtInBackends() []domain.Backend {
+	return []domain.Backend{
+		{
+			ID:               OpenRouterID,
+			Endpoint:         openRouterEndpoint,
+			APIKeyEnv:        openRouterAPIKeyEnv,
+			ConcurrencyLimit: openRouterConcurrencyLimit,
+		},
+		{
+			ID:               RakestrawHomeID,
+			Endpoint:         rakestrawHomeEndpoint,
+			APIKeyEnv:        rakestrawHomeAPIKeyEnv,
+			ConcurrencyLimit: rakestrawHomeConcurrencyLimit,
+		},
+	}
+}
+
 // GetBackend returns a defensive copy of the backend registered with id.
 func (r *Registry) GetBackend(id string) (domain.Backend, error) {
 	if r == nil {