diff --git a/metropolis/node/kubernetes/csi.go b/metropolis/node/kubernetes/csi.go
new file mode 100644
index 0000000..4b44a1a
--- /dev/null
+++ b/metropolis/node/kubernetes/csi.go
@@ -0,0 +1,246 @@
+// 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 kubernetes
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+	"regexp"
+
+	"github.com/container-storage-interface/spec/lib/go/csi"
+	"github.com/golang/protobuf/ptypes/wrappers"
+	"golang.org/x/sys/unix"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+	pluginregistration "k8s.io/kubelet/pkg/apis/pluginregistration/v1"
+
+	"git.monogon.dev/source/nexantic.git/metropolis/node/common/fsquota"
+	"git.monogon.dev/source/nexantic.git/metropolis/node/common/supervisor"
+	"git.monogon.dev/source/nexantic.git/metropolis/node/core/localstorage"
+	"git.monogon.dev/source/nexantic.git/metropolis/node/core/logtree"
+)
+
+// Derived from K8s spec for acceptable names, but shortened to 130 characters to avoid issues with
+// maximum path length. We don't provision longer names so this applies only if you manually create
+// a volume with a name of more than 130 characters.
+var acceptableNames = regexp.MustCompile("^[a-z][a-bz0-9-.]{0,128}[a-z0-9]$")
+
+const volumeDir = "volumes"
+
+type csiPluginServer struct {
+	KubeletDirectory *localstorage.DataKubernetesKubeletDirectory
+	VolumesDirectory *localstorage.DataVolumesDirectory
+
+	logger logtree.LeveledLogger
+}
+
+func (s *csiPluginServer) Run(ctx context.Context) error {
+	s.logger = supervisor.Logger(ctx)
+
+	pluginListener, err := net.ListenUnix("unix", &net.UnixAddr{Name: s.KubeletDirectory.Plugins.VFS.FullPath(), Net: "unix"})
+	if err != nil {
+		return fmt.Errorf("failed to listen on CSI socket: %w", err)
+	}
+	pluginListener.SetUnlinkOnClose(true)
+
+	pluginServer := grpc.NewServer()
+	csi.RegisterIdentityServer(pluginServer, s)
+	csi.RegisterNodeServer(pluginServer, s)
+	// Enable graceful shutdown since we don't have long-running RPCs and most of them shouldn't and can't be
+	// cancelled anyways.
+	if err := supervisor.Run(ctx, "csi-node", supervisor.GRPCServer(pluginServer, pluginListener, true)); err != nil {
+		return err
+	}
+
+	registrationListener, err := net.ListenUnix("unix", &net.UnixAddr{Name: s.KubeletDirectory.PluginsRegistry.VFSReg.FullPath(), Net: "unix"})
+	if err != nil {
+		return fmt.Errorf("failed to listen on CSI registration socket: %w", err)
+	}
+	registrationListener.SetUnlinkOnClose(true)
+
+	registrationServer := grpc.NewServer()
+	pluginregistration.RegisterRegistrationServer(registrationServer, s)
+	if err := supervisor.Run(ctx, "registration", supervisor.GRPCServer(registrationServer, registrationListener, true)); err != nil {
+		return err
+	}
+	supervisor.Signal(ctx, supervisor.SignalHealthy)
+	supervisor.Signal(ctx, supervisor.SignalDone)
+	return nil
+}
+
+func (*csiPluginServer) NodeStageVolume(ctx context.Context, req *csi.NodeStageVolumeRequest) (*csi.NodeStageVolumeResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method NodeStageVolume not supported")
+}
+
+func (*csiPluginServer) NodeUnstageVolume(ctx context.Context, req *csi.NodeUnstageVolumeRequest) (*csi.NodeUnstageVolumeResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method NodeUnstageVolume not supported")
+}
+
+func (s *csiPluginServer) NodePublishVolume(ctx context.Context, req *csi.NodePublishVolumeRequest) (*csi.NodePublishVolumeResponse, error) {
+	if !acceptableNames.MatchString(req.VolumeId) {
+		return nil, status.Error(codes.InvalidArgument, "invalid characters in volume id")
+	}
+
+	// TODO(q3k): move this logic to localstorage?
+	volumePath := filepath.Join(s.VolumesDirectory.FullPath(), req.VolumeId)
+
+	switch req.VolumeCapability.AccessMode.Mode {
+	case csi.VolumeCapability_AccessMode_SINGLE_NODE_WRITER:
+	case csi.VolumeCapability_AccessMode_SINGLE_NODE_READER_ONLY:
+	default:
+		return nil, status.Error(codes.InvalidArgument, "unsupported access mode")
+	}
+	switch req.VolumeCapability.AccessType.(type) {
+	case *csi.VolumeCapability_Mount:
+	default:
+		return nil, status.Error(codes.InvalidArgument, "unsupported access type")
+	}
+
+	err := unix.Mount(volumePath, req.TargetPath, "", unix.MS_BIND, "")
+	switch {
+	case err == unix.ENOENT:
+		return nil, status.Error(codes.NotFound, "volume not found")
+	case err != nil:
+		return nil, status.Errorf(codes.Unavailable, "failed to bind-mount volume: %v", err)
+	}
+
+	if req.Readonly {
+		err := unix.Mount(volumePath, req.TargetPath, "", unix.MS_BIND|unix.MS_REMOUNT|unix.MS_RDONLY, "")
+		if err != nil {
+			_ = unix.Unmount(req.TargetPath, 0) // Best-effort
+			return nil, status.Errorf(codes.Unavailable, "failed to remount volume: %v", err)
+		}
+	}
+	return &csi.NodePublishVolumeResponse{}, nil
+}
+
+func (*csiPluginServer) NodeUnpublishVolume(ctx context.Context, req *csi.NodeUnpublishVolumeRequest) (*csi.NodeUnpublishVolumeResponse, error) {
+	if err := unix.Unmount(req.TargetPath, 0); err != nil {
+		return nil, status.Errorf(codes.Unavailable, "failed to unmount volume: %v", err)
+	}
+	return &csi.NodeUnpublishVolumeResponse{}, nil
+}
+
+func (*csiPluginServer) NodeGetVolumeStats(ctx context.Context, req *csi.NodeGetVolumeStatsRequest) (*csi.NodeGetVolumeStatsResponse, error) {
+	quota, err := fsquota.GetQuota(req.VolumePath)
+	if os.IsNotExist(err) {
+		return nil, status.Error(codes.NotFound, "volume does not exist at this path")
+	} else if err != nil {
+		return nil, status.Errorf(codes.Unavailable, "failed to get quota: %v", err)
+	}
+
+	return &csi.NodeGetVolumeStatsResponse{
+		Usage: []*csi.VolumeUsage{
+			{
+				Total:     int64(quota.Bytes),
+				Unit:      csi.VolumeUsage_BYTES,
+				Used:      int64(quota.BytesUsed),
+				Available: int64(quota.Bytes - quota.BytesUsed),
+			},
+			{
+				Total:     int64(quota.Inodes),
+				Unit:      csi.VolumeUsage_INODES,
+				Used:      int64(quota.InodesUsed),
+				Available: int64(quota.Inodes - quota.InodesUsed),
+			},
+		},
+	}, nil
+}
+
+func (*csiPluginServer) NodeExpandVolume(ctx context.Context, req *csi.NodeExpandVolumeRequest) (*csi.NodeExpandVolumeResponse, error) {
+	if req.CapacityRange.LimitBytes <= 0 {
+		return nil, status.Error(codes.InvalidArgument, "invalid expanded volume size: at or below zero bytes")
+	}
+	if err := fsquota.SetQuota(req.VolumePath, uint64(req.CapacityRange.LimitBytes), 0); err != nil {
+		return nil, status.Errorf(codes.Unavailable, "failed to update quota: %v", err)
+	}
+	return &csi.NodeExpandVolumeResponse{CapacityBytes: req.CapacityRange.LimitBytes}, nil
+}
+
+func rpcCapability(cap csi.NodeServiceCapability_RPC_Type) *csi.NodeServiceCapability {
+	return &csi.NodeServiceCapability{
+		Type: &csi.NodeServiceCapability_Rpc{
+			Rpc: &csi.NodeServiceCapability_RPC{Type: cap},
+		},
+	}
+}
+
+func (*csiPluginServer) NodeGetCapabilities(ctx context.Context, req *csi.NodeGetCapabilitiesRequest) (*csi.NodeGetCapabilitiesResponse, error) {
+	return &csi.NodeGetCapabilitiesResponse{
+		Capabilities: []*csi.NodeServiceCapability{
+			rpcCapability(csi.NodeServiceCapability_RPC_EXPAND_VOLUME),
+			rpcCapability(csi.NodeServiceCapability_RPC_GET_VOLUME_STATS),
+		},
+	}, nil
+}
+
+func (*csiPluginServer) NodeGetInfo(ctx context.Context, req *csi.NodeGetInfoRequest) (*csi.NodeGetInfoResponse, error) {
+	hostname, err := os.Hostname()
+	if err != nil {
+		return nil, status.Errorf(codes.Unavailable, "failed to get node identity: %v", err)
+	}
+	return &csi.NodeGetInfoResponse{
+		NodeId: hostname,
+	}, nil
+}
+
+// CSI Identity endpoints
+func (*csiPluginServer) GetPluginInfo(ctx context.Context, req *csi.GetPluginInfoRequest) (*csi.GetPluginInfoResponse, error) {
+	return &csi.GetPluginInfoResponse{
+		Name:          "com.smalltown.vfs",
+		VendorVersion: "0.0.1", // TODO(lorenz): Maybe stamp?
+	}, nil
+}
+
+func (*csiPluginServer) GetPluginCapabilities(ctx context.Context, req *csi.GetPluginCapabilitiesRequest) (*csi.GetPluginCapabilitiesResponse, error) {
+	return &csi.GetPluginCapabilitiesResponse{
+		Capabilities: []*csi.PluginCapability{
+			{
+				Type: &csi.PluginCapability_VolumeExpansion_{
+					VolumeExpansion: &csi.PluginCapability_VolumeExpansion{
+						Type: csi.PluginCapability_VolumeExpansion_ONLINE,
+					},
+				},
+			},
+		},
+	}, nil
+}
+
+func (s *csiPluginServer) Probe(ctx context.Context, req *csi.ProbeRequest) (*csi.ProbeResponse, error) {
+	return &csi.ProbeResponse{Ready: &wrappers.BoolValue{Value: true}}, nil
+}
+
+// Registration endpoints
+func (s *csiPluginServer) GetInfo(ctx context.Context, req *pluginregistration.InfoRequest) (*pluginregistration.PluginInfo, error) {
+	return &pluginregistration.PluginInfo{
+		Type:              "CSIPlugin",
+		Name:              "com.smalltown.vfs",
+		Endpoint:          s.KubeletDirectory.Plugins.VFS.FullPath(),
+		SupportedVersions: []string{"1.2"}, // Keep in sync with container-storage-interface/spec package version
+	}, nil
+}
+
+func (s *csiPluginServer) NotifyRegistrationStatus(ctx context.Context, req *pluginregistration.RegistrationStatus) (*pluginregistration.RegistrationStatusResponse, error) {
+	if req.Error != "" {
+		s.logger.Warningf("Kubelet failed registering CSI plugin: %v", req.Error)
+	}
+	return &pluginregistration.RegistrationStatusResponse{}, nil
+}