diff --git a/cmd/dendrite/main.go b/cmd/dendrite/main.go
new file mode 100644
index 000000000..0e5ab4033
--- /dev/null
+++ b/cmd/dendrite/main.go
@@ -0,0 +1,46 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+
+	"github.com/matrix-org/dendrite/cmd/dendrite/personalities"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+)
+
+type starter func(base *setup.BaseDendrite, cfg *config.Dendrite)
+
+// nolint:gocyclo
+func main() {
+	cfg := setup.ParseFlags(true)
+	component := flag.Arg(0)
+
+	base := setup.NewBaseDendrite(cfg, component, false) // TODO
+	defer base.Close()                                   // nolint: errcheck
+
+	components := map[string]starter{
+		"appservice":       personalities.Appservice,
+		"clientapi":        personalities.ClientAPI,
+		"eduserver":        personalities.EDUServer,
+		"federationapi":    personalities.FederationAPI,
+		"federationsender": personalities.FederationSender,
+		"keyserver":        personalities.KeyServer,
+		"mediaapi":         personalities.MediaAPI,
+		"monolith":         personalities.Monolith,
+		"roomserver":       personalities.RoomServer,
+		"signingkeyserver": personalities.SigningKeyServer,
+		"syncapi":          personalities.SyncAPI,
+		"userapi":          personalities.UserAPI,
+	}
+
+	if start, ok := components[component]; ok {
+		start(base, cfg)
+	} else {
+		fmt.Printf("dendrite: unknown component %q\n", component)
+		fmt.Println("valid components:")
+		for c := range components {
+			fmt.Printf("- %s\n", c)
+		}
+	}
+}
diff --git a/cmd/dendrite/personalities/appservice.go b/cmd/dendrite/personalities/appservice.go
new file mode 100644
index 000000000..d8a641b5d
--- /dev/null
+++ b/cmd/dendrite/personalities/appservice.go
@@ -0,0 +1,21 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/appservice"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+)
+
+func Appservice(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	userAPI := base.UserAPIClient()
+	rsAPI := base.RoomserverHTTPClient()
+
+	intAPI := appservice.NewInternalAPI(base, userAPI, rsAPI)
+	appservice.AddInternalRoutes(base.InternalAPIMux, intAPI)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.AppServiceAPI.InternalAPI.Listen, // internal listener
+		setup.NoListener, // external listener
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/clientapi.go b/cmd/dendrite/personalities/clientapi.go
new file mode 100644
index 000000000..9caecc64b
--- /dev/null
+++ b/cmd/dendrite/personalities/clientapi.go
@@ -0,0 +1,31 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/clientapi"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/internal/transactions"
+)
+
+func ClientAPI(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	accountDB := base.CreateAccountsDB()
+	federation := base.CreateFederationClient()
+
+	asQuery := base.AppserviceHTTPClient()
+	rsAPI := base.RoomserverHTTPClient()
+	fsAPI := base.FederationSenderHTTPClient()
+	eduInputAPI := base.EDUServerClient()
+	userAPI := base.UserAPIClient()
+	keyAPI := base.KeyServerHTTPClient()
+
+	clientapi.AddPublicRoutes(
+		base.PublicClientAPIMux, &base.Cfg.ClientAPI, accountDB, federation,
+		rsAPI, eduInputAPI, asQuery, transactions.New(), fsAPI, userAPI, keyAPI, nil,
+	)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.ClientAPI.InternalAPI.Listen,
+		base.Cfg.ClientAPI.ExternalAPI.Listen,
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/eduserver.go b/cmd/dendrite/personalities/eduserver.go
new file mode 100644
index 000000000..ab0fbac4b
--- /dev/null
+++ b/cmd/dendrite/personalities/eduserver.go
@@ -0,0 +1,19 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/eduserver"
+	"github.com/matrix-org/dendrite/eduserver/cache"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+)
+
+func EDUServer(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	intAPI := eduserver.NewInternalAPI(base, cache.New(), base.UserAPIClient())
+	eduserver.AddInternalRoutes(base.InternalAPIMux, intAPI)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.EDUServer.InternalAPI.Listen, // internal listener
+		setup.NoListener,                      // external listener
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/federationapi.go b/cmd/dendrite/personalities/federationapi.go
new file mode 100644
index 000000000..69f498f19
--- /dev/null
+++ b/cmd/dendrite/personalities/federationapi.go
@@ -0,0 +1,29 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/federationapi"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+)
+
+func FederationAPI(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	userAPI := base.UserAPIClient()
+	federation := base.CreateFederationClient()
+	serverKeyAPI := base.SigningKeyServerHTTPClient()
+	keyRing := serverKeyAPI.KeyRing()
+	fsAPI := base.FederationSenderHTTPClient()
+	rsAPI := base.RoomserverHTTPClient()
+	keyAPI := base.KeyServerHTTPClient()
+
+	federationapi.AddPublicRoutes(
+		base.PublicFederationAPIMux, base.PublicKeyAPIMux,
+		&base.Cfg.FederationAPI, userAPI, federation, keyRing,
+		rsAPI, fsAPI, base.EDUServerClient(), keyAPI,
+	)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.FederationAPI.InternalAPI.Listen,
+		base.Cfg.FederationAPI.ExternalAPI.Listen,
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/federationsender.go b/cmd/dendrite/personalities/federationsender.go
new file mode 100644
index 000000000..965aca202
--- /dev/null
+++ b/cmd/dendrite/personalities/federationsender.go
@@ -0,0 +1,26 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/federationsender"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+)
+
+func FederationSender(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	federation := base.CreateFederationClient()
+
+	serverKeyAPI := base.SigningKeyServerHTTPClient()
+	keyRing := serverKeyAPI.KeyRing()
+
+	rsAPI := base.RoomserverHTTPClient()
+	fsAPI := federationsender.NewInternalAPI(
+		base, federation, rsAPI, keyRing,
+	)
+	federationsender.AddInternalRoutes(base.InternalAPIMux, fsAPI)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.FederationSender.InternalAPI.Listen, // internal listener
+		setup.NoListener, // external listener
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/keyserver.go b/cmd/dendrite/personalities/keyserver.go
new file mode 100644
index 000000000..fbcd21bd8
--- /dev/null
+++ b/cmd/dendrite/personalities/keyserver.go
@@ -0,0 +1,20 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/keyserver"
+)
+
+func KeyServer(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	intAPI := keyserver.NewInternalAPI(&base.Cfg.KeyServer, base.CreateFederationClient())
+	intAPI.SetUserAPI(base.UserAPIClient())
+
+	keyserver.AddInternalRoutes(base.InternalAPIMux, intAPI)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.KeyServer.InternalAPI.Listen, // internal listener
+		setup.NoListener,                      // external listener
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/mediaapi.go b/cmd/dendrite/personalities/mediaapi.go
new file mode 100644
index 000000000..da648bf28
--- /dev/null
+++ b/cmd/dendrite/personalities/mediaapi.go
@@ -0,0 +1,20 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/mediaapi"
+)
+
+func MediaAPI(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	userAPI := base.UserAPIClient()
+	client := base.CreateClient()
+
+	mediaapi.AddPublicRoutes(base.PublicMediaAPIMux, &base.Cfg.MediaAPI, userAPI, client)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.MediaAPI.InternalAPI.Listen,
+		base.Cfg.MediaAPI.ExternalAPI.Listen,
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/monolith.go b/cmd/dendrite/personalities/monolith.go
new file mode 100644
index 000000000..b6da580de
--- /dev/null
+++ b/cmd/dendrite/personalities/monolith.go
@@ -0,0 +1,144 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/appservice"
+	"github.com/matrix-org/dendrite/eduserver"
+	"github.com/matrix-org/dendrite/eduserver/cache"
+	"github.com/matrix-org/dendrite/federationsender"
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/keyserver"
+	"github.com/matrix-org/dendrite/roomserver"
+	"github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/dendrite/signingkeyserver"
+	"github.com/matrix-org/dendrite/userapi"
+	"github.com/sirupsen/logrus"
+)
+
+func Monolith(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	httpAddr := config.HTTPAddress("http://" + *httpBindAddr)
+	httpsAddr := config.HTTPAddress("https://" + *httpsBindAddr)
+	httpAPIAddr := httpAddr
+
+	if *enableHTTPAPIs {
+		logrus.Warnf("DANGER! The -api option is enabled, exposing internal APIs on %q!", *apiBindAddr)
+		httpAPIAddr = config.HTTPAddress("http://" + *apiBindAddr)
+		// If the HTTP APIs are enabled then we need to update the Listen
+		// statements in the configuration so that we know where to find
+		// the API endpoints. They'll listen on the same port as the monolith
+		// itself.
+		cfg.AppServiceAPI.InternalAPI.Connect = httpAPIAddr
+		cfg.ClientAPI.InternalAPI.Connect = httpAPIAddr
+		cfg.EDUServer.InternalAPI.Connect = httpAPIAddr
+		cfg.FederationAPI.InternalAPI.Connect = httpAPIAddr
+		cfg.FederationSender.InternalAPI.Connect = httpAPIAddr
+		cfg.KeyServer.InternalAPI.Connect = httpAPIAddr
+		cfg.MediaAPI.InternalAPI.Connect = httpAPIAddr
+		cfg.RoomServer.InternalAPI.Connect = httpAPIAddr
+		cfg.SigningKeyServer.InternalAPI.Connect = httpAPIAddr
+		cfg.SyncAPI.InternalAPI.Connect = httpAPIAddr
+	}
+
+	base := setup.NewBaseDendrite(cfg, "Monolith", *enableHTTPAPIs)
+	defer base.Close() // nolint: errcheck
+
+	accountDB := base.CreateAccountsDB()
+	federation := base.CreateFederationClient()
+
+	skAPI := signingkeyserver.NewInternalAPI(
+		&base.Cfg.SigningKeyServer, federation, base.Caches,
+	)
+	if base.UseHTTPAPIs {
+		signingkeyserver.AddInternalRoutes(base.InternalAPIMux, skAPI, base.Caches)
+		skAPI = base.SigningKeyServerHTTPClient()
+	}
+	keyRing := skAPI.KeyRing()
+
+	rsImpl := roomserver.NewInternalAPI(
+		base, keyRing,
+	)
+	// call functions directly on the impl unless running in HTTP mode
+	rsAPI := rsImpl
+	if base.UseHTTPAPIs {
+		roomserver.AddInternalRoutes(base.InternalAPIMux, rsImpl)
+		rsAPI = base.RoomserverHTTPClient()
+	}
+	if traceInternal {
+		rsAPI = &api.RoomserverInternalAPITrace{
+			Impl: rsAPI,
+		}
+	}
+
+	fsAPI := federationsender.NewInternalAPI(
+		base, federation, rsAPI, keyRing,
+	)
+	if base.UseHTTPAPIs {
+		federationsender.AddInternalRoutes(base.InternalAPIMux, fsAPI)
+		fsAPI = base.FederationSenderHTTPClient()
+	}
+	// The underlying roomserver implementation needs to be able to call the fedsender.
+	// This is different to rsAPI which can be the http client which doesn't need this dependency
+	rsImpl.SetFederationSenderAPI(fsAPI)
+
+	keyAPI := keyserver.NewInternalAPI(&base.Cfg.KeyServer, fsAPI)
+	userAPI := userapi.NewInternalAPI(accountDB, &cfg.UserAPI, cfg.Derived.ApplicationServices, keyAPI)
+	keyAPI.SetUserAPI(userAPI)
+
+	eduInputAPI := eduserver.NewInternalAPI(
+		base, cache.New(), userAPI,
+	)
+	if base.UseHTTPAPIs {
+		eduserver.AddInternalRoutes(base.InternalAPIMux, eduInputAPI)
+		eduInputAPI = base.EDUServerClient()
+	}
+
+	asAPI := appservice.NewInternalAPI(base, userAPI, rsAPI)
+	if base.UseHTTPAPIs {
+		appservice.AddInternalRoutes(base.InternalAPIMux, asAPI)
+		asAPI = base.AppserviceHTTPClient()
+	}
+
+	monolith := setup.Monolith{
+		Config:    base.Cfg,
+		AccountDB: accountDB,
+		Client:    base.CreateClient(),
+		FedClient: federation,
+		KeyRing:   keyRing,
+
+		AppserviceAPI:       asAPI,
+		EDUInternalAPI:      eduInputAPI,
+		FederationSenderAPI: fsAPI,
+		RoomserverAPI:       rsAPI,
+		ServerKeyAPI:        skAPI,
+		UserAPI:             userAPI,
+		KeyAPI:              keyAPI,
+	}
+	monolith.AddAllPublicRoutes(
+		base.PublicClientAPIMux,
+		base.PublicFederationAPIMux,
+		base.PublicKeyAPIMux,
+		base.PublicMediaAPIMux,
+	)
+
+	// Expose the matrix APIs directly rather than putting them under a /api path.
+	go func() {
+		base.SetupAndServeHTTP(
+			httpAPIAddr, // internal API
+			httpAddr,    // external API
+			nil, nil,    // TLS settings
+		)
+	}()
+	// Handle HTTPS if certificate and key are provided
+	if *certFile != "" && *keyFile != "" {
+		go func() {
+			base.SetupAndServeHTTP(
+				setup.NoListener,  // internal API
+				httpsAddr,         // external API
+				certFile, keyFile, // TLS settings
+			)
+		}()
+	}
+
+	// We want to block forever to let the HTTP and HTTPS handler serve the APIs
+	select {}
+}
diff --git a/cmd/dendrite/personalities/roomserver.go b/cmd/dendrite/personalities/roomserver.go
new file mode 100644
index 000000000..37de6fc70
--- /dev/null
+++ b/cmd/dendrite/personalities/roomserver.go
@@ -0,0 +1,23 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/roomserver"
+)
+
+func RoomServer(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	serverKeyAPI := base.SigningKeyServerHTTPClient()
+	keyRing := serverKeyAPI.KeyRing()
+
+	fsAPI := base.FederationSenderHTTPClient()
+	rsAPI := roomserver.NewInternalAPI(base, keyRing)
+	rsAPI.SetFederationSenderAPI(fsAPI)
+	roomserver.AddInternalRoutes(base.InternalAPIMux, rsAPI)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.RoomServer.InternalAPI.Listen, // internal listener
+		setup.NoListener,                       // external listener
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/signingkeyserver.go b/cmd/dendrite/personalities/signingkeyserver.go
new file mode 100644
index 000000000..f94508022
--- /dev/null
+++ b/cmd/dendrite/personalities/signingkeyserver.go
@@ -0,0 +1,20 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/signingkeyserver"
+)
+
+func SigningKeyServer(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	federation := base.CreateFederationClient()
+
+	intAPI := signingkeyserver.NewInternalAPI(&base.Cfg.SigningKeyServer, federation, base.Caches)
+	signingkeyserver.AddInternalRoutes(base.InternalAPIMux, intAPI, base.Caches)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.SigningKeyServer.InternalAPI.Listen,
+		setup.NoListener,
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/syncapi.go b/cmd/dendrite/personalities/syncapi.go
new file mode 100644
index 000000000..9355e1b93
--- /dev/null
+++ b/cmd/dendrite/personalities/syncapi.go
@@ -0,0 +1,26 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/syncapi"
+)
+
+func SyncAPI(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	userAPI := base.UserAPIClient()
+	federation := base.CreateFederationClient()
+
+	rsAPI := base.RoomserverHTTPClient()
+
+	syncapi.AddPublicRoutes(
+		base.PublicClientAPIMux, userAPI, rsAPI,
+		base.KeyServerHTTPClient(),
+		federation, &cfg.SyncAPI,
+	)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.SyncAPI.InternalAPI.Listen,
+		base.Cfg.SyncAPI.ExternalAPI.Listen,
+		nil, nil,
+	)
+}
diff --git a/cmd/dendrite/personalities/userapi.go b/cmd/dendrite/personalities/userapi.go
new file mode 100644
index 000000000..15cb681f4
--- /dev/null
+++ b/cmd/dendrite/personalities/userapi.go
@@ -0,0 +1,21 @@
+package personalities
+
+import (
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dendrite/internal/setup"
+	"github.com/matrix-org/dendrite/userapi"
+)
+
+func UserAPI(base *setup.BaseDendrite, cfg *config.Dendrite) {
+	accountDB := base.CreateAccountsDB()
+
+	userAPI := userapi.NewInternalAPI(accountDB, &cfg.UserAPI, cfg.Derived.ApplicationServices, base.KeyServerHTTPClient())
+
+	userapi.AddInternalRoutes(base.InternalAPIMux, userAPI)
+
+	base.SetupAndServeHTTP(
+		base.Cfg.UserAPI.InternalAPI.Listen, // internal listener
+		setup.NoListener,                    // external listener
+		nil, nil,
+	)
+}