diff --git a/metropolis/test/localregistry/BUILD.bazel b/metropolis/test/localregistry/BUILD.bazel
new file mode 100644
index 0000000..548960a
--- /dev/null
+++ b/metropolis/test/localregistry/BUILD.bazel
@@ -0,0 +1,19 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "localregistry",
+    srcs = ["localregistry.go"],
+    importpath = "source.monogon.dev/metropolis/test/localregistry",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//metropolis/test/localregistry/spec",
+        "@com_github_docker_distribution//:distribution",
+        "@com_github_docker_distribution//manifest/manifestlist",
+        "@com_github_docker_distribution//manifest/ocischema",
+        "@com_github_docker_distribution//manifest/schema2",
+        "@com_github_docker_distribution//reference",
+        "@com_github_opencontainers_go_digest//:go-digest",
+        "@io_bazel_rules_go//go/runfiles:go_default_library",
+        "@org_golang_google_protobuf//encoding/prototext",
+    ],
+)
diff --git a/metropolis/test/localregistry/def.bzl b/metropolis/test/localregistry/def.bzl
new file mode 100644
index 0000000..c5fc560
--- /dev/null
+++ b/metropolis/test/localregistry/def.bzl
@@ -0,0 +1,35 @@
+#load("@io_bazel_rules_docker//container:providers.bzl", "ImageInfo")
+
+def _localregistry_manifest_impl(ctx):
+    manifest_out = ctx.actions.declare_file(ctx.label.name+".prototxt")
+
+    images = []
+    referenced = [manifest_out]
+    for i in ctx.attr.images:
+        image_file = i.files.to_list()[0]
+        image = struct(
+            name = i.label.package + "/" + i.label.name,
+            path = image_file.short_path,
+        )
+        referenced.append(image_file)
+        images.append(image)
+
+    ctx.actions.write(manifest_out, proto.encode_text(struct(images = images)))
+    return [DefaultInfo(runfiles = ctx.runfiles(files = referenced), files = depset([manifest_out]))]
+
+
+localregistry_manifest = rule(
+    implementation = _localregistry_manifest_impl,
+    doc = """
+        Builds a manifest for serving images directly from the build files.
+    """,
+    attrs = {
+        "images": attr.label_list(
+            mandatory = True,
+            doc = """
+                List of images to be served from the local registry.
+            """,
+           providers = [],
+        ),
+    },
+)
diff --git a/metropolis/test/localregistry/localregistry.go b/metropolis/test/localregistry/localregistry.go
new file mode 100644
index 0000000..120eb61
--- /dev/null
+++ b/metropolis/test/localregistry/localregistry.go
@@ -0,0 +1,172 @@
+// Package localregistry implements a read-only OCI Distribution / Docker
+// V2 container image registry backed by local layers.
+package localregistry
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+
+	"github.com/bazelbuild/rules_go/go/runfiles"
+	"github.com/docker/distribution"
+	"github.com/docker/distribution/manifest/manifestlist"
+	"github.com/docker/distribution/manifest/ocischema"
+	"github.com/docker/distribution/manifest/schema2"
+	"github.com/docker/distribution/reference"
+	"github.com/opencontainers/go-digest"
+	"google.golang.org/protobuf/encoding/prototext"
+
+	"source.monogon.dev/metropolis/test/localregistry/spec"
+)
+
+type Server struct {
+	manifests map[string][]byte
+	blobs     map[digest.Digest]blobMeta
+}
+
+type blobMeta struct {
+	filePath      string
+	mediaType     string
+	contentLength int64
+}
+
+func manifestDescriptorFromBazel(image *spec.Image) (manifestlist.ManifestDescriptor, error) {
+	indexPath, err := runfiles.Rlocation(filepath.Join("_main", image.Path, "index.json"))
+	if err != nil {
+		return manifestlist.ManifestDescriptor{}, fmt.Errorf("while locating manifest list file: %w", err)
+	}
+
+	manifestListRaw, err := os.ReadFile(indexPath)
+	if err != nil {
+		return manifestlist.ManifestDescriptor{}, fmt.Errorf("while opening manifest list file: %w", err)
+	}
+
+	var imageManifestList manifestlist.ManifestList
+	if err := json.Unmarshal(manifestListRaw, &imageManifestList); err != nil {
+		return manifestlist.ManifestDescriptor{}, fmt.Errorf("while unmarshaling manifest list for %q: %w", image.Name, err)
+	}
+
+	if len(imageManifestList.Manifests) != 1 {
+		return manifestlist.ManifestDescriptor{}, fmt.Errorf("unexpected manifest list length > 1")
+	}
+
+	return imageManifestList.Manifests[0], nil
+}
+
+func manifestFromBazel(s *Server, image *spec.Image, md manifestlist.ManifestDescriptor) (ocischema.Manifest, error) {
+	manifestPath, err := runfiles.Rlocation(filepath.Join("_main", image.Path, "blobs", md.Digest.Algorithm().String(), md.Digest.Hex()))
+	if err != nil {
+		return ocischema.Manifest{}, fmt.Errorf("while locating manifest file: %w", err)
+	}
+	manifestRaw, err := os.ReadFile(manifestPath)
+	if err != nil {
+		return ocischema.Manifest{}, fmt.Errorf("while opening manifest file: %w", err)
+	}
+
+	var imageManifest ocischema.Manifest
+	if err := json.Unmarshal(manifestRaw, &imageManifest); err != nil {
+		return ocischema.Manifest{}, fmt.Errorf("while unmarshaling manifest for %q: %w", image.Name, err)
+	}
+
+	// For Digest lookups
+	s.manifests[image.Name] = manifestRaw
+	s.manifests[md.Digest.String()] = manifestRaw
+
+	return imageManifest, nil
+}
+
+func addBazelBlobFromDescriptor(s *Server, image *spec.Image, dd distribution.Descriptor) error {
+	path, err := runfiles.Rlocation(filepath.Join("_main", image.Path, "blobs", dd.Digest.Algorithm().String(), dd.Digest.Hex()))
+	if err != nil {
+		return fmt.Errorf("while locating blob: %w", err)
+	}
+	s.blobs[dd.Digest] = blobMeta{filePath: path, mediaType: dd.MediaType, contentLength: dd.Size}
+	return nil
+}
+
+func FromBazelManifest(mb []byte) (*Server, error) {
+	var bazelManifest spec.Manifest
+	if err := prototext.Unmarshal(mb, &bazelManifest); err != nil {
+		log.Fatalf("failed to parse manifest: %v", err)
+	}
+	s := Server{
+		manifests: make(map[string][]byte),
+		blobs:     make(map[digest.Digest]blobMeta),
+	}
+	for _, i := range bazelManifest.Images {
+		md, err := manifestDescriptorFromBazel(i)
+		if err != nil {
+			return nil, err
+		}
+
+		if err := addBazelBlobFromDescriptor(&s, i, md.Descriptor); err != nil {
+			return nil, err
+		}
+
+		m, err := manifestFromBazel(&s, i, md)
+		if err != nil {
+			return nil, err
+		}
+
+		if err := addBazelBlobFromDescriptor(&s, i, m.Config); err != nil {
+			return nil, err
+		}
+		for _, l := range m.Layers {
+			if err := addBazelBlobFromDescriptor(&s, i, l); err != nil {
+				return nil, err
+			}
+		}
+	}
+	return &s, nil
+}
+
+var (
+	versionCheckEp = regexp.MustCompile(`^/v2/$`)
+	manifestEp     = regexp.MustCompile("^/v2/(" + reference.NameRegexp.String() + ")/manifests/(" + reference.TagRegexp.String() + "|" + digest.DigestRegexp.String() + ")$")
+	blobEp         = regexp.MustCompile("^/v2/(" + reference.NameRegexp.String() + ")/blobs/(" + digest.DigestRegexp.String() + ")$")
+)
+
+func (s *Server) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if req.Method != http.MethodGet && req.Method != http.MethodHead {
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		fmt.Fprintf(w, "Registry is read-only, only GET and HEAD are allowed\n")
+		return
+	}
+	w.Header().Set("Content-Type", "application/json")
+	if versionCheckEp.MatchString(req.URL.Path) {
+		w.WriteHeader(http.StatusOK)
+		fmt.Fprintf(w, "{}")
+		return
+	} else if matches := manifestEp.FindStringSubmatch(req.URL.Path); len(matches) > 0 {
+		name := matches[1]
+		manifest, ok := s.manifests[name]
+		if !ok {
+			w.WriteHeader(http.StatusNotFound)
+			fmt.Fprintf(w, "Image not found")
+			return
+		}
+		w.Header().Set("Content-Type", schema2.MediaTypeManifest)
+		w.Header().Set("Content-Length", strconv.FormatInt(int64(len(manifest)), 10))
+		w.WriteHeader(http.StatusOK)
+		io.Copy(w, bytes.NewReader(manifest))
+	} else if matches := blobEp.FindStringSubmatch(req.URL.Path); len(matches) > 0 {
+		bm, ok := s.blobs[digest.Digest(matches[2])]
+		if !ok {
+			w.WriteHeader(http.StatusNotFound)
+			fmt.Fprintf(w, "Blob not found")
+			return
+		}
+		w.Header().Set("Content-Type", bm.mediaType)
+		w.Header().Set("Content-Length", strconv.FormatInt(bm.contentLength, 10))
+		http.ServeFile(w, req, bm.filePath)
+	} else {
+		w.WriteHeader(http.StatusNotFound)
+	}
+}
diff --git a/metropolis/test/localregistry/spec/BUILD.bazel b/metropolis/test/localregistry/spec/BUILD.bazel
new file mode 100644
index 0000000..71253d1
--- /dev/null
+++ b/metropolis/test/localregistry/spec/BUILD.bazel
@@ -0,0 +1,23 @@
+load("@rules_proto//proto:defs.bzl", "proto_library")
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+load("@io_bazel_rules_go//proto:def.bzl", "go_proto_library")
+
+proto_library(
+    name = "spec_proto",
+    srcs = ["manifest.proto"],
+    visibility = ["//visibility:public"],
+)
+
+go_proto_library(
+    name = "spec_go_proto",
+    importpath = "source.monogon.dev/metropolis/test/localregistry/spec",
+    proto = ":spec_proto",
+    visibility = ["//visibility:public"],
+)
+
+go_library(
+    name = "spec",
+    embed = [":spec_go_proto"],
+    importpath = "source.monogon.dev/metropolis/test/localregistry/spec",
+    visibility = ["//visibility:public"],
+)
diff --git a/metropolis/test/localregistry/spec/gomod-generated-placeholder.go b/metropolis/test/localregistry/spec/gomod-generated-placeholder.go
new file mode 100644
index 0000000..f09cd57
--- /dev/null
+++ b/metropolis/test/localregistry/spec/gomod-generated-placeholder.go
@@ -0,0 +1 @@
+package spec
diff --git a/metropolis/test/localregistry/spec/manifest.proto b/metropolis/test/localregistry/spec/manifest.proto
new file mode 100644
index 0000000..bb53581
--- /dev/null
+++ b/metropolis/test/localregistry/spec/manifest.proto
@@ -0,0 +1,19 @@
+syntax = "proto3";
+
+package monogon.metropolis.pkg.localregistry;
+
+option go_package = "source.monogon.dev/metropolis/test/localregistry/spec";
+
+// Single image metadata
+message Image {
+    // Name of the image (no domain or tag, just slash-separated path)
+    string name = 1;
+    // Path to the image
+    string path = 2;
+}
+
+// Main message
+message Manifest {
+    // List of images for the local registry
+    repeated Image images = 1;
+}
\ No newline at end of file