diff --git a/pkg/manifests/errors.go b/pkg/manifests/errors.go
new file mode 100644
index 00000000000..8398d7efcfe
--- /dev/null
+++ b/pkg/manifests/errors.go
@@ -0,0 +1,16 @@
+package manifests
+
+import (
+	"errors"
+)
+
+var (
+	// ErrDigestNotFound is returned when we look for an image instance
+	// with a particular digest in a list or index, and fail to find it.
+	ErrDigestNotFound = errors.New("no image instance matching the specified digest was found in the list or index")
+	// ErrManifestTypeNotSupported is returned when we attempt to parse a
+	// manifest with a known MIME type as a list or index, or when we attempt
+	// to serialize a list or index to a manifest with a MIME type that we
+	// don't know how to encode.
+	ErrManifestTypeNotSupported = errors.New("manifest type not supported")
+)
diff --git a/pkg/manifests/manifests.go b/pkg/manifests/manifests.go
new file mode 100644
index 00000000000..ea9495ee73a
--- /dev/null
+++ b/pkg/manifests/manifests.go
@@ -0,0 +1,493 @@
+package manifests
+
+import (
+	"encoding/json"
+	"os"
+
+	"github.com/containers/image/v5/manifest"
+	digest "github.com/opencontainers/go-digest"
+	imgspec "github.com/opencontainers/image-spec/specs-go"
+	v1 "github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/pkg/errors"
+)
+
+// List is a generic interface for manipulating a manifest list or an image
+// index.
+type List interface {
+	AddInstance(manifestDigest digest.Digest, manifestSize int64, manifestType, os, architecture, osVersion string, osFeatures []string, variant string, features []string, annotations []string) error
+	Remove(instanceDigest digest.Digest) error
+
+	SetURLs(instanceDigest digest.Digest, urls []string) error
+	URLs(instanceDigest digest.Digest) ([]string, error)
+
+	SetAnnotations(instanceDigest *digest.Digest, annotations map[string]string) error
+	Annotations(instanceDigest *digest.Digest) (map[string]string, error)
+
+	SetOS(instanceDigest digest.Digest, os string) error
+	OS(instanceDigest digest.Digest) (string, error)
+
+	SetArchitecture(instanceDigest digest.Digest, arch string) error
+	Architecture(instanceDigest digest.Digest) (string, error)
+
+	SetOSVersion(instanceDigest digest.Digest, osVersion string) error
+	OSVersion(instanceDigest digest.Digest) (string, error)
+
+	SetVariant(instanceDigest digest.Digest, variant string) error
+	Variant(instanceDigest digest.Digest) (string, error)
+
+	SetFeatures(instanceDigest digest.Digest, features []string) error
+	Features(instanceDigest digest.Digest) ([]string, error)
+
+	SetOSFeatures(instanceDigest digest.Digest, osFeatures []string) error
+	OSFeatures(instanceDigest digest.Digest) ([]string, error)
+
+	Serialize(mimeType string) ([]byte, error)
+	Instances() []digest.Digest
+	OCIv1() *v1.Index
+	Docker() *manifest.Schema2List
+
+	findDocker(instanceDigest digest.Digest) (*manifest.Schema2ManifestDescriptor, error)
+	findOCIv1(instanceDigest digest.Digest) (*v1.Descriptor, error)
+}
+
+type list struct {
+	docker manifest.Schema2List
+	oci    v1.Index
+}
+
+// OCIv1 returns the list as a Docker schema 2 list.  The returned structure should NOT be modified.
+func (l *list) Docker() *manifest.Schema2List {
+	return &l.docker
+}
+
+// OCIv1 returns the list as an OCI image index.  The returned structure should NOT be modified.
+func (l *list) OCIv1() *v1.Index {
+	return &l.oci
+}
+
+// Create creates a new list.
+func Create() List {
+	return &list{
+		docker: manifest.Schema2List{
+			SchemaVersion: 2,
+			MediaType:     manifest.DockerV2ListMediaType,
+		},
+		oci: v1.Index{
+			Versioned: imgspec.Versioned{SchemaVersion: 2},
+		},
+	}
+}
+
+// AddInstance adds an entry for the specified manifest digest, with assorted
+// additional information specified in parameters, to the list or index.
+func (l *list) AddInstance(manifestDigest digest.Digest, manifestSize int64, manifestType, osName, architecture, osVersion string, osFeatures []string, variant string, features []string, annotations []string) error {
+	if err := l.Remove(manifestDigest); err != nil && !os.IsNotExist(errors.Cause(err)) {
+		return err
+	}
+
+	schema2platform := manifest.Schema2PlatformSpec{
+		Architecture: architecture,
+		OS:           osName,
+		OSVersion:    osVersion,
+		OSFeatures:   osFeatures,
+		Variant:      variant,
+		Features:     features,
+	}
+	l.docker.Manifests = append(l.docker.Manifests, manifest.Schema2ManifestDescriptor{
+		Schema2Descriptor: manifest.Schema2Descriptor{
+			MediaType: manifestType,
+			Size:      manifestSize,
+			Digest:    manifestDigest,
+		},
+		Platform: schema2platform,
+	})
+
+	ociv1platform := v1.Platform{
+		Architecture: architecture,
+		OS:           osName,
+		OSVersion:    osVersion,
+		OSFeatures:   osFeatures,
+		Variant:      variant,
+	}
+	l.oci.Manifests = append(l.oci.Manifests, v1.Descriptor{
+		MediaType: manifestType,
+		Size:      manifestSize,
+		Digest:    manifestDigest,
+		Platform:  &ociv1platform,
+	})
+
+	return nil
+}
+
+// Remove filters out any instances in the list which match the specified digest.
+func (l *list) Remove(instanceDigest digest.Digest) error {
+	err := errors.Wrapf(os.ErrNotExist, "no instance matching digest %q found in manifest list", instanceDigest)
+	newDockerManifests := make([]manifest.Schema2ManifestDescriptor, 0, len(l.docker.Manifests))
+	for i := range l.docker.Manifests {
+		if l.docker.Manifests[i].Digest != instanceDigest {
+			newDockerManifests = append(newDockerManifests, l.docker.Manifests[i])
+		} else {
+			err = nil
+		}
+	}
+	l.docker.Manifests = newDockerManifests
+	newOCIv1Manifests := make([]v1.Descriptor, 0, len(l.oci.Manifests))
+	for i := range l.oci.Manifests {
+		if l.oci.Manifests[i].Digest != instanceDigest {
+			newOCIv1Manifests = append(newOCIv1Manifests, l.oci.Manifests[i])
+		} else {
+			err = nil
+		}
+	}
+	l.oci.Manifests = newOCIv1Manifests
+	return err
+}
+
+func (l *list) findDocker(instanceDigest digest.Digest) (*manifest.Schema2ManifestDescriptor, error) {
+	for i := range l.docker.Manifests {
+		if l.docker.Manifests[i].Digest == instanceDigest {
+			return &l.docker.Manifests[i], nil
+		}
+	}
+	return nil, errors.Wrapf(ErrDigestNotFound, "no Docker manifest matching digest %q was found in list", instanceDigest.String())
+}
+
+func (l *list) findOCIv1(instanceDigest digest.Digest) (*v1.Descriptor, error) {
+	for i := range l.oci.Manifests {
+		if l.oci.Manifests[i].Digest == instanceDigest {
+			return &l.oci.Manifests[i], nil
+		}
+	}
+	return nil, errors.Wrapf(ErrDigestNotFound, "no OCI manifest matching digest %q was found in list", instanceDigest.String())
+}
+
+// SetURLs sets the URLs where the manifest might also be found.
+func (l *list) SetURLs(instanceDigest digest.Digest, urls []string) error {
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return err
+	}
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return err
+	}
+	oci.URLs = append([]string{}, urls...)
+	docker.URLs = append([]string{}, urls...)
+	return nil
+}
+
+// URLs retrieves the locations from which this object might possibly be downloaded.
+func (l *list) URLs(instanceDigest digest.Digest) ([]string, error) {
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return nil, err
+	}
+	return append([]string{}, oci.URLs...), nil
+}
+
+// SetAnnotations sets annotations on the image index, or on a specific manifest.
+// The field is specific to the OCI image index format, and is not present in Docker manifest lists.
+func (l *list) SetAnnotations(instanceDigest *digest.Digest, annotations map[string]string) error {
+	a := &l.oci.Annotations
+	if instanceDigest != nil {
+		oci, err := l.findOCIv1(*instanceDigest)
+		if err != nil {
+			return err
+		}
+		a = &oci.Annotations
+	}
+	(*a) = make(map[string]string)
+	for k, v := range annotations {
+		(*a)[k] = v
+	}
+	return nil
+}
+
+// Annotations retrieves the annotations which have been set on the image index, or on one instance.
+// The field is specific to the OCI image index format, and is not present in Docker manifest lists.
+func (l *list) Annotations(instanceDigest *digest.Digest) (map[string]string, error) {
+	a := l.oci.Annotations
+	if instanceDigest != nil {
+		oci, err := l.findOCIv1(*instanceDigest)
+		if err != nil {
+			return nil, err
+		}
+		a = oci.Annotations
+	}
+	annotations := make(map[string]string)
+	for k, v := range a {
+		annotations[k] = v
+	}
+	return annotations, nil
+}
+
+// SetOS sets the OS field in the platform information associated with the instance with the specified digest.
+func (l *list) SetOS(instanceDigest digest.Digest, os string) error {
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return err
+	}
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return err
+	}
+	docker.Platform.OS = os
+	oci.Platform.OS = os
+	return nil
+}
+
+// OS retrieves the OS field in the platform information associated with the instance with the specified digest.
+func (l *list) OS(instanceDigest digest.Digest) (string, error) {
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return "", err
+	}
+	return oci.Platform.OS, nil
+}
+
+// SetArchitecture sets the Architecture field in the platform information associated with the instance with the specified digest.
+func (l *list) SetArchitecture(instanceDigest digest.Digest, arch string) error {
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return err
+	}
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return err
+	}
+	docker.Platform.Architecture = arch
+	oci.Platform.Architecture = arch
+	return nil
+}
+
+// Architecture retrieves the Architecture field in the platform information associated with the instance with the specified digest.
+func (l *list) Architecture(instanceDigest digest.Digest) (string, error) {
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return "", err
+	}
+	return oci.Platform.Architecture, nil
+}
+
+// SetOSVersion sets the OSVersion field in the platform information associated with the instance with the specified digest.
+func (l *list) SetOSVersion(instanceDigest digest.Digest, osVersion string) error {
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return err
+	}
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return err
+	}
+	docker.Platform.OSVersion = osVersion
+	oci.Platform.OSVersion = osVersion
+	return nil
+}
+
+// OSVersion retrieves the OSVersion field in the platform information associated with the instance with the specified digest.
+func (l *list) OSVersion(instanceDigest digest.Digest) (string, error) {
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return "", err
+	}
+	return oci.Platform.OSVersion, nil
+}
+
+// SetVariant sets the Variant field in the platform information associated with the instance with the specified digest.
+func (l *list) SetVariant(instanceDigest digest.Digest, variant string) error {
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return err
+	}
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return err
+	}
+	docker.Platform.Variant = variant
+	oci.Platform.Variant = variant
+	return nil
+}
+
+// Variant retrieves the Variant field in the platform information associated with the instance with the specified digest.
+func (l *list) Variant(instanceDigest digest.Digest) (string, error) {
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return "", err
+	}
+	return oci.Platform.Variant, nil
+}
+
+// SetFeatures sets the features list in the platform information associated with the instance with the specified digest.
+// The field is specific to the Docker manifest list format, and is not present in OCI's image indexes.
+func (l *list) SetFeatures(instanceDigest digest.Digest, features []string) error {
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return err
+	}
+	docker.Platform.Features = append([]string{}, features...)
+	// no OCI equivalent
+	return nil
+}
+
+// Features retrieves the features list from the platform information associated with the instance with the specified digest.
+// The field is specific to the Docker manifest list format, and is not present in OCI's image indexes.
+func (l *list) Features(instanceDigest digest.Digest) ([]string, error) {
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return nil, err
+	}
+	return append([]string{}, docker.Platform.Features...), nil
+}
+
+// SetOSFeatures sets the OS features list in the platform information associated with the instance with the specified digest.
+func (l *list) SetOSFeatures(instanceDigest digest.Digest, osFeatures []string) error {
+	docker, err := l.findDocker(instanceDigest)
+	if err != nil {
+		return err
+	}
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return err
+	}
+	docker.Platform.OSFeatures = append([]string{}, osFeatures...)
+	oci.Platform.OSFeatures = append([]string{}, osFeatures...)
+	return nil
+}
+
+// OSFeatures retrieves the OS features list from the platform information associated with the instance with the specified digest.
+func (l *list) OSFeatures(instanceDigest digest.Digest) ([]string, error) {
+	oci, err := l.findOCIv1(instanceDigest)
+	if err != nil {
+		return nil, err
+	}
+	return append([]string{}, oci.Platform.OSFeatures...), nil
+}
+
+// FromBlob builds a list from an encoded manifest list or image index.
+func FromBlob(manifestBytes []byte) (List, error) {
+	manifestType := manifest.GuessMIMEType(manifestBytes)
+	list := &list{
+		docker: manifest.Schema2List{
+			SchemaVersion: 2,
+			MediaType:     manifest.DockerV2ListMediaType,
+		},
+		oci: v1.Index{
+			Versioned: imgspec.Versioned{SchemaVersion: 2},
+		},
+	}
+	switch manifestType {
+	default:
+		return nil, errors.Wrapf(ErrManifestTypeNotSupported, "unable to load manifest list: unsupported format %q", manifestType)
+	case manifest.DockerV2ListMediaType:
+		if err := json.Unmarshal(manifestBytes, &list.docker); err != nil {
+			return nil, errors.Wrapf(err, "unable to parse Docker manifest list from image")
+		}
+		for _, m := range list.docker.Manifests {
+			list.oci.Manifests = append(list.oci.Manifests, v1.Descriptor{
+				MediaType: m.Schema2Descriptor.MediaType,
+				Size:      m.Schema2Descriptor.Size,
+				Digest:    m.Schema2Descriptor.Digest,
+				Platform: &v1.Platform{
+					Architecture: m.Platform.Architecture,
+					OS:           m.Platform.OS,
+					OSVersion:    m.Platform.OSVersion,
+					OSFeatures:   m.Platform.OSFeatures,
+					Variant:      m.Platform.Variant,
+				},
+			})
+		}
+	case v1.MediaTypeImageIndex:
+		if err := json.Unmarshal(manifestBytes, &list.oci); err != nil {
+			return nil, errors.Wrapf(err, "unable to parse OCIv1 manifest list")
+		}
+		for _, m := range list.oci.Manifests {
+			platform := m.Platform
+			if platform == nil {
+				platform = &v1.Platform{}
+			}
+			list.docker.Manifests = append(list.docker.Manifests, manifest.Schema2ManifestDescriptor{
+				Schema2Descriptor: manifest.Schema2Descriptor{
+					MediaType: m.MediaType,
+					Size:      m.Size,
+					Digest:    m.Digest,
+				},
+				Platform: manifest.Schema2PlatformSpec{
+					Architecture: platform.Architecture,
+					OS:           platform.OS,
+					OSVersion:    platform.OSVersion,
+					OSFeatures:   platform.OSFeatures,
+					Variant:      platform.Variant,
+				},
+			})
+		}
+	}
+	return list, nil
+}
+
+func (l *list) preferOCI() bool {
+	// If we have any data that's only in the OCI format, use that.
+	for _, m := range l.oci.Manifests {
+		if len(m.URLs) > 0 {
+			return true
+		}
+		if len(m.Annotations) > 0 {
+			return true
+		}
+	}
+	// If we have any data that's only in the Docker format, use that.
+	for _, m := range l.docker.Manifests {
+		if len(m.Platform.Features) > 0 {
+			return false
+		}
+	}
+	// If we have no manifests, remember that the Docker format is
+	// explicitly typed, so use that.  Otherwise, default to using the OCI
+	// format.
+	return len(l.docker.Manifests) != 0
+}
+
+// Serialize encodes the list using the specified format, or by selecting one
+// which it thinks is appropriate.
+func (l *list) Serialize(mimeType string) ([]byte, error) {
+	var manifestBytes []byte
+	switch mimeType {
+	case "":
+		if l.preferOCI() {
+			manifest, err := json.Marshal(&l.oci)
+			if err != nil {
+				return nil, errors.Wrapf(err, "error marshalling OCI image index")
+			}
+			manifestBytes = manifest
+		} else {
+			manifest, err := json.Marshal(&l.docker)
+			if err != nil {
+				return nil, errors.Wrapf(err, "error marshalling Docker manifest list")
+			}
+			manifestBytes = manifest
+		}
+	case v1.MediaTypeImageIndex:
+		manifest, err := json.Marshal(&l.oci)
+		if err != nil {
+			return nil, errors.Wrapf(err, "error marshalling OCI image index")
+		}
+		manifestBytes = manifest
+	case manifest.DockerV2ListMediaType:
+		manifest, err := json.Marshal(&l.docker)
+		if err != nil {
+			return nil, errors.Wrapf(err, "error marshalling Docker manifest list")
+		}
+		manifestBytes = manifest
+	default:
+		return nil, errors.Wrapf(ErrManifestTypeNotSupported, "serializing list to type %q not implemented", mimeType)
+	}
+	return manifestBytes, nil
+}
+
+// Instances returns the list of image instances mentioned in this list.
+func (l *list) Instances() []digest.Digest {
+	instances := make([]digest.Digest, 0, len(l.oci.Manifests))
+	for _, instance := range l.oci.Manifests {
+		instances = append(instances, instance.Digest)
+	}
+	return instances
+}
diff --git a/pkg/manifests/manifests_test.go b/pkg/manifests/manifests_test.go
new file mode 100644
index 00000000000..1f160c384e1
--- /dev/null
+++ b/pkg/manifests/manifests_test.go
@@ -0,0 +1,369 @@
+package manifests
+
+import (
+	"io/ioutil"
+	"os"
+	"reflect"
+	"testing"
+
+	"github.com/containers/image/v5/manifest"
+	"github.com/containers/storage/pkg/reexec"
+	digest "github.com/opencontainers/go-digest"
+	v1 "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+const (
+	expectedInstance = digest.Digest("sha256:c829b1810d2dbb456e74a695fd3847530c8319e5a95dca623e9f1b1b89020d8b")
+	ociFixture       = "testdata/fedora.index.json"
+	dockerFixture    = "testdata/fedora.list.json"
+)
+
+var (
+	_ List = &list{}
+)
+
+func TestMain(m *testing.M) {
+	if reexec.Init() {
+		return
+	}
+	os.Exit(m.Run())
+}
+
+func TestCreate(t *testing.T) {
+	list := Create()
+	if list == nil {
+		t.Fatalf("error creating an empty list")
+	}
+}
+
+func TestFromBlob(t *testing.T) {
+	for _, version := range []string{
+		ociFixture,
+		dockerFixture,
+	} {
+		bytes, err := ioutil.ReadFile(version)
+		if err != nil {
+			t.Fatalf("error loading %s: %v", version, err)
+		}
+		list, err := FromBlob(bytes)
+		if err != nil {
+			t.Fatalf("error parsing %s: %v", version, err)
+		}
+		if len(list.Docker().Manifests) != len(list.OCIv1().Manifests) {
+			t.Fatalf("%s: expected the same number of manifests, but %d != %d", version, len(list.Docker().Manifests), len(list.OCIv1().Manifests))
+		}
+		for i := range list.Docker().Manifests {
+			d := list.Docker().Manifests[i]
+			o := list.OCIv1().Manifests[i]
+			if d.Platform.OS != o.Platform.OS {
+				t.Fatalf("%s: expected the same OS", version)
+			}
+			if d.Platform.Architecture != o.Platform.Architecture {
+				t.Fatalf("%s: expected the same Architecture", version)
+			}
+		}
+	}
+}
+
+func TestAddInstance(t *testing.T) {
+	manifestBytes, err := ioutil.ReadFile("testdata/fedora-minimal.schema2.json")
+	if err != nil {
+		t.Fatalf("error loading testdata/fedora-minimal.schema2.json: %v", err)
+	}
+	manifestType := manifest.GuessMIMEType(manifestBytes)
+	manifestDigest, err := manifest.Digest(manifestBytes)
+	if err != nil {
+		t.Fatalf("error digesting testdata/fedora-minimal.schema2.json: %v", err)
+	}
+	for _, version := range []string{
+		ociFixture,
+		dockerFixture,
+	} {
+		bytes, err := ioutil.ReadFile(version)
+		if err != nil {
+			t.Fatalf("error loading %s: %v", version, err)
+		}
+		list, err := FromBlob(bytes)
+		if err != nil {
+			t.Fatalf("error parsing %s: %v", version, err)
+		}
+		if err = list.AddInstance(manifestDigest, int64(len(manifestBytes)), manifestType, "linux", "amd64", "", nil, "", nil, nil); err != nil {
+			t.Fatalf("adding an instance failed in %s: %v", version, err)
+		}
+		if d, err := list.findDocker(manifestDigest); d == nil || err != nil {
+			t.Fatalf("adding an instance failed in %s: %v", version, err)
+		}
+		if o, err := list.findOCIv1(manifestDigest); o == nil || err != nil {
+			t.Fatalf("adding an instance failed in %s: %v", version, err)
+		}
+	}
+}
+
+func TestRemove(t *testing.T) {
+	bytes, err := ioutil.ReadFile(ociFixture)
+	if err != nil {
+		t.Fatalf("error loading blob: %v", err)
+	}
+	list, err := FromBlob(bytes)
+	if err != nil {
+		t.Fatalf("error parsing blob: %v", err)
+	}
+	before := len(list.OCIv1().Manifests)
+	instanceDigest := expectedInstance
+	if d, err := list.findDocker(instanceDigest); d == nil || err != nil {
+		t.Fatalf("finding expected instance failed: %v", err)
+	}
+	if o, err := list.findOCIv1(instanceDigest); o == nil || err != nil {
+		t.Fatalf("finding expected instance failed: %v", err)
+	}
+	err = list.Remove(instanceDigest)
+	if err != nil {
+		t.Fatalf("error parsing blob: %v", err)
+	}
+	after := len(list.Docker().Manifests)
+	if after != before-1 {
+		t.Fatalf("removing instance should have succeeded")
+	}
+	if d, err := list.findDocker(instanceDigest); d != nil || err == nil {
+		t.Fatalf("finding instance should have failed")
+	}
+	if o, err := list.findOCIv1(instanceDigest); o != nil || err == nil {
+		t.Fatalf("finding instance should have failed")
+	}
+}
+
+func testString(t *testing.T, values []string, set func(List, digest.Digest, string) error, get func(List, digest.Digest) (string, error)) {
+	bytes, err := ioutil.ReadFile(ociFixture)
+	if err != nil {
+		t.Fatalf("error loading blob: %v", err)
+	}
+	list, err := FromBlob(bytes)
+	if err != nil {
+		t.Fatalf("error parsing blob: %v", err)
+	}
+	for _, testString := range values {
+		if err = set(list, expectedInstance, testString); err != nil {
+			t.Fatalf("error setting %q: %v", testString, err)
+		}
+		b, err := list.Serialize("")
+		if err != nil {
+			t.Fatalf("error serializing list: %v", err)
+		}
+		list, err := FromBlob(b)
+		if err != nil {
+			t.Fatalf("error parsing list: %v", err)
+		}
+		value, err := get(list, expectedInstance)
+		if err != nil {
+			t.Fatalf("error retrieving value %q: %v", testString, err)
+		}
+		if value != testString {
+			t.Fatalf("expected value %q, got %q: %v", value, testString, err)
+		}
+	}
+}
+
+func testStringSlice(t *testing.T, values [][]string, set func(List, digest.Digest, []string) error, get func(List, digest.Digest) ([]string, error)) {
+	bytes, err := ioutil.ReadFile(ociFixture)
+	if err != nil {
+		t.Fatalf("error loading blob: %v", err)
+	}
+	list, err := FromBlob(bytes)
+	if err != nil {
+		t.Fatalf("error parsing blob: %v", err)
+	}
+	for _, testSlice := range values {
+		if err = set(list, expectedInstance, testSlice); err != nil {
+			t.Fatalf("error setting %v: %v", testSlice, err)
+		}
+		b, err := list.Serialize("")
+		if err != nil {
+			t.Fatalf("error serializing list: %v", err)
+		}
+		list, err := FromBlob(b)
+		if err != nil {
+			t.Fatalf("error parsing list: %v", err)
+		}
+		values, err := get(list, expectedInstance)
+		if err != nil {
+			t.Fatalf("error retrieving value %v: %v", testSlice, err)
+		}
+		if !reflect.DeepEqual(values, testSlice) {
+			t.Fatalf("expected values %v, got %v: %v", testSlice, values, err)
+		}
+	}
+}
+
+func testMap(t *testing.T, values []map[string]string, set func(List, *digest.Digest, map[string]string) error, get func(List, *digest.Digest) (map[string]string, error)) {
+	bytes, err := ioutil.ReadFile(ociFixture)
+	if err != nil {
+		t.Fatalf("error loading blob: %v", err)
+	}
+	list, err := FromBlob(bytes)
+	if err != nil {
+		t.Fatalf("error parsing blob: %v", err)
+	}
+	instance := expectedInstance
+	for _, instanceDigest := range []*digest.Digest{nil, &instance} {
+		for _, testMap := range values {
+			if err = set(list, instanceDigest, testMap); err != nil {
+				t.Fatalf("error setting %v: %v", testMap, err)
+			}
+			b, err := list.Serialize("")
+			if err != nil {
+				t.Fatalf("error serializing list: %v", err)
+			}
+			list, err := FromBlob(b)
+			if err != nil {
+				t.Fatalf("error parsing list: %v", err)
+			}
+			values, err := get(list, instanceDigest)
+			if err != nil {
+				t.Fatalf("error retrieving value %v: %v", testMap, err)
+			}
+			if len(values) != len(testMap) {
+				t.Fatalf("expected %d map entries, got %d", len(testMap), len(values))
+			}
+			for k, v := range testMap {
+				if values[k] != v {
+					t.Fatalf("expected map value %q=%q, got %q", k, v, values[k])
+				}
+			}
+		}
+	}
+}
+
+func TestAnnotations(t *testing.T) {
+	testMap(t,
+		[]map[string]string{{"A": "B", "C": "D"}, {"E": "F", "G": "H"}},
+		func(l List, i *digest.Digest, m map[string]string) error {
+			return l.SetAnnotations(i, m)
+		},
+		func(l List, i *digest.Digest) (map[string]string, error) {
+			return l.Annotations(i)
+		},
+	)
+}
+
+func TestArchitecture(t *testing.T) {
+	testString(t,
+		[]string{"abacus", "sliderule"},
+		func(l List, i digest.Digest, s string) error {
+			return l.SetArchitecture(i, s)
+		},
+		func(l List, i digest.Digest) (string, error) {
+			return l.Architecture(i)
+		},
+	)
+}
+
+func TestFeatures(t *testing.T) {
+	testStringSlice(t,
+		[][]string{{"chrome", "hubcaps"}, {"climate", "control"}},
+		func(l List, i digest.Digest, s []string) error {
+			return l.SetFeatures(i, s)
+		},
+		func(l List, i digest.Digest) ([]string, error) {
+			return l.Features(i)
+		},
+	)
+}
+
+func TestOS(t *testing.T) {
+	testString(t,
+		[]string{"linux", "darwin"},
+		func(l List, i digest.Digest, s string) error {
+			return l.SetOS(i, s)
+		},
+		func(l List, i digest.Digest) (string, error) {
+			return l.OS(i)
+		},
+	)
+}
+
+func TestOSFeatures(t *testing.T) {
+	testStringSlice(t,
+		[][]string{{"ipv6", "containers"}, {"nested", "virtualization"}},
+		func(l List, i digest.Digest, s []string) error {
+			return l.SetOSFeatures(i, s)
+		},
+		func(l List, i digest.Digest) ([]string, error) {
+			return l.OSFeatures(i)
+		},
+	)
+}
+
+func TestOSVersion(t *testing.T) {
+	testString(t,
+		[]string{"el7", "el8"},
+		func(l List, i digest.Digest, s string) error {
+			return l.SetOSVersion(i, s)
+		},
+		func(l List, i digest.Digest) (string, error) {
+			return l.OSVersion(i)
+		},
+	)
+}
+
+func TestURLs(t *testing.T) {
+	testStringSlice(t,
+		[][]string{{"https://example.com", "https://example.net"}, {"http://example.com", "http://example.net"}},
+		func(l List, i digest.Digest, s []string) error {
+			return l.SetURLs(i, s)
+		},
+		func(l List, i digest.Digest) ([]string, error) {
+			return l.URLs(i)
+		},
+	)
+}
+
+func TestVariant(t *testing.T) {
+	testString(t,
+		[]string{"workstation", "cloud", "server"},
+		func(l List, i digest.Digest, s string) error {
+			return l.SetVariant(i, s)
+		},
+		func(l List, i digest.Digest) (string, error) {
+			return l.Variant(i)
+		},
+	)
+}
+
+func TestSerialize(t *testing.T) {
+	for _, version := range []string{
+		ociFixture,
+		dockerFixture,
+	} {
+		bytes, err := ioutil.ReadFile(version)
+		if err != nil {
+			t.Fatalf("error loading %s: %v", version, err)
+		}
+		list, err := FromBlob(bytes)
+		if err != nil {
+			t.Fatalf("error parsing %s: %v", version, err)
+		}
+		for _, mimeType := range []string{"", v1.MediaTypeImageIndex, manifest.DockerV2ListMediaType} {
+			b, err := list.Serialize(mimeType)
+			if err != nil {
+				t.Fatalf("error serializing %s with type %q: %v", version, mimeType, err)
+			}
+			l, err := FromBlob(b)
+			if err != nil {
+				t.Fatalf("error parsing %s re-encoded as %q: %v\n%s", version, mimeType, err, string(b))
+			}
+			if !reflect.DeepEqual(list.Docker().Manifests, l.Docker().Manifests) {
+				t.Fatalf("re-encoded %s as %q was different\n%#v\n%#v", version, mimeType, list, l)
+			}
+			for i := range list.OCIv1().Manifests {
+				manifest := list.OCIv1().Manifests[i]
+				m := l.OCIv1().Manifests[i]
+				if manifest.Digest != m.Digest ||
+					manifest.MediaType != m.MediaType ||
+					manifest.Size != m.Size ||
+					!reflect.DeepEqual(list.OCIv1().Manifests[i].Platform, l.OCIv1().Manifests[i].Platform) {
+					t.Fatalf("re-encoded %s OCI %d as %q was different\n%#v\n%#v", version, i, mimeType, list, l)
+				}
+			}
+		}
+	}
+}
diff --git a/pkg/manifests/testdata/fedora-minimal.schema2.json b/pkg/manifests/testdata/fedora-minimal.schema2.json
new file mode 100644
index 00000000000..4d294837f7a
--- /dev/null
+++ b/pkg/manifests/testdata/fedora-minimal.schema2.json
@@ -0,0 +1,16 @@
+{
+    "schemaVersion": 2,
+    "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+    "config": {
+        "mediaType": "application/vnd.docker.container.image.v1+json",
+        "size": 1316,
+        "digest": "sha256:847a6054047619b8908f61e0211e3480ab20ce4b6cf17b03db081322ade301d3"
+    },
+    "layers": [
+        {
+            "mediaType": "application/vnd.docker.image.rootfs.diff.tar.gzip",
+            "size": 42163967,
+            "digest": "sha256:8fad33c002fa130aceec4fd0cadc8bad0d7561667ab24aee75dea825be933de0"
+        }
+    ]
+}
diff --git a/pkg/manifests/testdata/fedora.index.json b/pkg/manifests/testdata/fedora.index.json
new file mode 100644
index 00000000000..503f80d0404
--- /dev/null
+++ b/pkg/manifests/testdata/fedora.index.json
@@ -0,0 +1,45 @@
+{
+    "manifests": [
+        {
+            "digest": "sha256:f81f09918379d5442d20dff82a298f29698197035e737f76e511d5af422cabd7",
+            "mediaType": "application/vnd.oci.image.manifest.v1+json",
+            "platform": {
+                "architecture": "amd64",
+                "os": "linux"
+            },
+            "size": 529
+        },
+        {
+            "digest": "sha256:c829b1810d2dbb456e74a695fd3847530c8319e5a95dca623e9f1b1b89020d8b",
+            "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+            "platform": {
+                "architecture": "arm64",
+                "os": "linux",
+                "variant": "v8"
+            },
+            "size": 529
+        },
+        {
+            "digest": "sha256:68b26da78d8790df143479ec2e3174c57cedb1c2e84ce1b2675d942d6848f2da",
+            "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+            "platform": {
+                "architecture": "ppc64le",
+                "os": "linux"
+            },
+            "size": 529
+        },
+        {
+            "digest": "sha256:15352d97781ffdf357bf3459c037be3efac4133dc9070c2dce7eca7c05c3e736",
+            "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+            "platform": {
+                "architecture": "s390x",
+                "os": "linux"
+            },
+            "size": 529
+        }
+    ],
+    "schemaVersion": 2,
+    "annotations": {
+      "foo": "bar"
+    }
+}
diff --git a/pkg/manifests/testdata/fedora.list.json b/pkg/manifests/testdata/fedora.list.json
new file mode 100644
index 00000000000..11898ba3754
--- /dev/null
+++ b/pkg/manifests/testdata/fedora.list.json
@@ -0,0 +1,43 @@
+{
+    "manifests": [
+        {
+            "digest": "sha256:f81f09918379d5442d20dff82a298f29698197035e737f76e511d5af422cabd7",
+            "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+            "platform": {
+                "architecture": "amd64",
+                "os": "linux"
+            },
+            "size": 529
+        },
+        {
+            "digest": "sha256:c829b1810d2dbb456e74a695fd3847530c8319e5a95dca623e9f1b1b89020d8b",
+            "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+            "platform": {
+                "architecture": "arm64",
+                "os": "linux",
+                "variant": "v8"
+            },
+            "size": 529
+        },
+        {
+            "digest": "sha256:68b26da78d8790df143479ec2e3174c57cedb1c2e84ce1b2675d942d6848f2da",
+            "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+            "platform": {
+                "architecture": "ppc64le",
+                "os": "linux"
+            },
+            "size": 529
+        },
+        {
+            "digest": "sha256:15352d97781ffdf357bf3459c037be3efac4133dc9070c2dce7eca7c05c3e736",
+            "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+            "platform": {
+                "architecture": "s390x",
+                "os": "linux"
+            },
+            "size": 529
+        }
+    ],
+    "mediaType": "application/vnd.docker.distribution.manifest.list.v2+json",
+    "schemaVersion": 2
+}
diff --git a/pkg/manifests/testdata/fedora.schema2.json b/pkg/manifests/testdata/fedora.schema2.json
new file mode 100644
index 00000000000..43cd2bb3f8d
--- /dev/null
+++ b/pkg/manifests/testdata/fedora.schema2.json
@@ -0,0 +1,16 @@
+{
+    "schemaVersion": 2,
+    "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
+    "config": {
+        "mediaType": "application/vnd.docker.container.image.v1+json",
+        "size": 2037,
+        "digest": "sha256:e9ed59d2baf72308f3a811ebc49ff3f4e0175abf40bf636bea0160759c637999"
+    },
+    "layers": [
+        {
+            "mediaType": "application/vnd.docker.image.rootfs.diff.tar.gzip",
+            "size": 69532283,
+            "digest": "sha256:5a915a173fbc36dc8e1410afdd9de2b08f71efb226f8eb1ebcdc00a1acbced62"
+        }
+    ]
+}