diff --git a/core/node/libp2p/pubsub.go b/core/node/libp2p/pubsub.go
index 072d74ee142..2730df14430 100644
--- a/core/node/libp2p/pubsub.go
+++ b/core/node/libp2p/pubsub.go
@@ -1,26 +1,75 @@
 package libp2p
 
 import (
+	"context"
+	"errors"
+	"fmt"
+
+	datastore "github.com/ipfs/go-datastore"
 	pubsub "github.com/libp2p/go-libp2p-pubsub"
 	"github.com/libp2p/go-libp2p/core/discovery"
 	"github.com/libp2p/go-libp2p/core/host"
+	"github.com/libp2p/go-libp2p/core/peer"
 	"go.uber.org/fx"
 
 	"github.com/ipfs/kubo/core/node/helpers"
+	"github.com/ipfs/kubo/repo"
 )
 
+type P2PPubSubIn struct {
+	fx.In
+
+	Repo      repo.Repo
+	Host      host.Host
+	Discovery discovery.Discovery
+}
+
 func FloodSub(pubsubOptions ...pubsub.Option) interface{} {
-	return func(mctx helpers.MetricsCtx, lc fx.Lifecycle, host host.Host, disc discovery.Discovery) (service *pubsub.PubSub, err error) {
-		return pubsub.NewFloodSub(helpers.LifecycleCtx(mctx, lc), host, append(pubsubOptions, pubsub.WithDiscovery(disc))...)
+	return func(mctx helpers.MetricsCtx, lc fx.Lifecycle, params P2PPubSubIn) (service *pubsub.PubSub, err error) {
+		return pubsub.NewFloodSub(
+			helpers.LifecycleCtx(mctx, lc),
+			params.Host,
+			append(pubsubOptions,
+				pubsub.WithDiscovery(params.Discovery),
+				pubsub.WithDefaultValidator(pubsub.NewBasicSeqnoValidator(makePubSubMetadataStore(params.Repo.Datastore()))))...,
+		)
 	}
 }
 
 func GossipSub(pubsubOptions ...pubsub.Option) interface{} {
-	return func(mctx helpers.MetricsCtx, lc fx.Lifecycle, host host.Host, disc discovery.Discovery) (service *pubsub.PubSub, err error) {
-		return pubsub.NewGossipSub(helpers.LifecycleCtx(mctx, lc), host, append(
-			pubsubOptions,
-			pubsub.WithDiscovery(disc),
-			pubsub.WithFloodPublish(true))...,
+	return func(mctx helpers.MetricsCtx, lc fx.Lifecycle, params P2PPubSubIn) (service *pubsub.PubSub, err error) {
+		return pubsub.NewGossipSub(
+			helpers.LifecycleCtx(mctx, lc),
+			params.Host,
+			append(
+				pubsubOptions,
+				pubsub.WithDiscovery(params.Discovery),
+				pubsub.WithFloodPublish(true),
+				pubsub.WithDefaultValidator(pubsub.NewBasicSeqnoValidator(makePubSubMetadataStore(params.Repo.Datastore()))))...,
 		)
 	}
 }
+
+func makePubSubMetadataStore(ds datastore.Datastore) pubsub.PeerMetadataStore {
+	return &pubsubMetadataStore{ds: ds}
+}
+
+type pubsubMetadataStore struct {
+	ds datastore.Datastore
+}
+
+func (m *pubsubMetadataStore) Get(ctx context.Context, p peer.ID) ([]byte, error) {
+	k := datastore.NewKey(fmt.Sprintf("/pubsub/seqno/%s", p))
+
+	v, err := m.ds.Get(ctx, k)
+	if err != nil && errors.Is(err, datastore.ErrNotFound) {
+		return nil, nil
+	}
+
+	return v, err
+}
+
+func (m *pubsubMetadataStore) Put(ctx context.Context, p peer.ID, v []byte) error {
+	k := datastore.NewKey(fmt.Sprintf("/pubsub/seqno/%s", p))
+	return m.ds.Put(ctx, k, v)
+}
diff --git a/test/integration/pubsub_msg_seen_cache_test.go b/test/integration/pubsub_msg_seen_cache_test.go
index 85cc8ae9f1e..702677ad35a 100644
--- a/test/integration/pubsub_msg_seen_cache_test.go
+++ b/test/integration/pubsub_msg_seen_cache_test.go
@@ -30,7 +30,7 @@ import (
 )
 
 func TestMessageSeenCacheTTL(t *testing.T) {
-	t.Skip("skipping PubSub seen cache TTL test due to flakiness")
+	t.Skip("the behaviour of seen cache has changed wrt to timing and this test cannot capture this behaviour now; it also has unit tests in go-libp2p-pubsub.")
 	if err := RunMessageSeenCacheTTLTest(t, "10s"); err != nil {
 		t.Fatal(err)
 	}