diff --git a/core/internal/common/BUILD.bazel b/core/internal/common/BUILD.bazel
index 4312b88..1adbfd8 100644
--- a/core/internal/common/BUILD.bazel
+++ b/core/internal/common/BUILD.bazel
@@ -2,19 +2,8 @@
 
 go_library(
     name = "go_default_library",
-    srcs = [
-        "grpc.go",
-        "service.go",
-        "setup.go",
-        "storage.go",
-        "util.go",
-    ],
+    srcs = ["setup.go"],
     importpath = "git.monogon.dev/source/nexantic.git/core/internal/common",
-    visibility = ["//core:__subpackages__"],
-    deps = [
-        "//core/api/api:go_default_library",
-        "//core/api/common:go_default_library",
-        "@org_golang_google_grpc//:go_default_library",
-        "@org_uber_go_zap//:go_default_library",
-    ],
+    visibility = ["//:__subpackages__"],
+    deps = ["//core/api/api:go_default_library"],
 )
diff --git a/core/internal/common/grpc/BUILD.bazel b/core/internal/common/grpc/BUILD.bazel
new file mode 100644
index 0000000..85661c6
--- /dev/null
+++ b/core/internal/common/grpc/BUILD.bazel
@@ -0,0 +1,12 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["grpc.go"],
+    importpath = "git.monogon.dev/source/nexantic.git/core/internal/common/grpc",
+    visibility = ["//:__subpackages__"],
+    deps = [
+        "//core/api/api:go_default_library",
+        "@org_golang_google_grpc//:go_default_library",
+    ],
+)
diff --git a/core/internal/common/grpc.go b/core/internal/common/grpc/grpc.go
similarity index 98%
rename from core/internal/common/grpc.go
rename to core/internal/common/grpc/grpc.go
index 5512a5c..e9cfed0 100644
--- a/core/internal/common/grpc.go
+++ b/core/internal/common/grpc/grpc.go
@@ -14,7 +14,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package common
+package grpc
 
 import (
 	"git.monogon.dev/source/nexantic.git/core/generated/api"
diff --git a/core/internal/common/service/BUILD.bazel b/core/internal/common/service/BUILD.bazel
new file mode 100644
index 0000000..a06ca83
--- /dev/null
+++ b/core/internal/common/service/BUILD.bazel
@@ -0,0 +1,9 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["service.go"],
+    importpath = "git.monogon.dev/source/nexantic.git/core/internal/common/service",
+    visibility = ["//:__subpackages__"],
+    deps = ["@org_uber_go_zap//:go_default_library"],
+)
diff --git a/core/internal/common/service.go b/core/internal/common/service/service.go
similarity index 96%
rename from core/internal/common/service.go
rename to core/internal/common/service/service.go
index 3bdc1f9..e093ff6 100644
--- a/core/internal/common/service.go
+++ b/core/internal/common/service/service.go
@@ -14,7 +14,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package common
+package service
 
 import (
 	"errors"
@@ -74,7 +74,7 @@
 	return nil
 }
 
-// Stop stops the service. THis is an atomic operation and should only be called on a running service.
+// Stop stops the service. This is an atomic operation and should only be called on a running service.
 func (b *BaseService) Stop() error {
 	b.mutex.Lock()
 	defer b.mutex.Unlock()
diff --git a/core/internal/common/setup.go b/core/internal/common/setup.go
index 331d29a..1124d27 100644
--- a/core/internal/common/setup.go
+++ b/core/internal/common/setup.go
@@ -18,20 +18,25 @@
 
 import "git.monogon.dev/source/nexantic.git/core/generated/api"
 
+// TODO(leo): merge api and node packages and get rid of this extra layer of indirection?
+
 type (
 	SetupService interface {
 		CurrentState() SmalltownState
 		GetJoinClusterToken() string
-		SetupNewCluster(name string, externalHost string) error
+		SetupNewCluster() error
 		EnterJoinClusterMode() error
-		JoinCluster(name string, clusterString string, externalHost string, certs *api.ConsensusCertificates) error
+		JoinCluster(initialCluster string, certs *api.ConsensusCertificates) error
 	}
 
 	SmalltownState string
 )
 
 const (
-	StateSetupMode       SmalltownState = "setup"
+	// Node is unprovisioned and waits for Setup to be called.
+	StateSetupMode SmalltownState = "setup"
+	// Setup() has been called, node waits for a JoinCluster or BootstrapCluster call.
 	StateClusterJoinMode SmalltownState = "join"
-	StateConfigured      SmalltownState = "configured"
+	// Node is fully provisioned.
+	StateConfigured SmalltownState = "configured"
 )
diff --git a/core/internal/common/storage.go b/core/internal/common/storage.go
deleted file mode 100644
index caaa155..0000000
--- a/core/internal/common/storage.go
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright 2020 The Monogon Project Authors.
-//
-// SPDX-License-Identifier: Apache-2.0
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package common
-
-import "errors"
-
-type DataPlace uint32
-
-const (
-	PlaceESP  DataPlace = 0
-	PlaceData           = 1
-)
-
-var (
-	// ErrNotInitialized will be returned when trying to access a place that's not yet initialized
-	ErrNotInitialized = errors.New("This place is not initialized")
-	// ErrUnknownPlace will be returned when trying to access a place that's not known
-	ErrUnknownPlace = errors.New("This place is not known")
-)
-
-type StorageManager interface {
-	GetPathInPlace(place DataPlace, path string) (string, error)
-}
diff --git a/core/internal/common/util.go b/core/internal/common/util.go
deleted file mode 100644
index fc8a72b..0000000
--- a/core/internal/common/util.go
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright 2020 The Monogon Project Authors.
-//
-// SPDX-License-Identifier: Apache-2.0
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package common
-
-import "git.monogon.dev/source/nexantic.git/core/generated/common"
-
-func MapToKVs(input map[string]string) []*common.KV {
-	kvs := make([]*common.KV, len(input))
-
-	i := 0
-	for key, item := range input {
-		kvs[i] = &common.KV{
-			Key:   key,
-			Value: []byte(item),
-		}
-	}
-
-	return kvs
-}