diff --git a/Gopkg.lock b/Gopkg.lock
index e7d72ae..c4bb16e 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -11,11 +11,11 @@
 
 [[projects]]
   branch = "monitor-mempool-operations"
-  digest = "1:3c7349246af8fcbaccd2f7fb8c6b3ffefe8e270d11606b4dd512289147deecfe"
+  digest = "1:ed4fa2fe2ea95f23e336eb44796e971f5bd285e879dee6f9bee6067604904431"
   name = "github.com/ecadlabs/go-tezos"
   packages = ["."]
   pruneopts = "UT"
-  revision = "e92de97b5b89346b71af72e79df4a539f1932305"
+  revision = "fbbb6f7a57d122f85ca042752a4edd5ba8156ebc"
 
 [[projects]]
   digest = "1:db2e37856e0f3e8ad322792ca2ede9bcf821f4d482ca0ef300e6a9d85776a99a"
@@ -117,7 +117,7 @@
   name = "golang.org/x/sys"
   packages = ["windows"]
   pruneopts = "UT"
-  revision = "d432491b91382bba9c2a91776aa47c9430183a6f"
+  revision = "c5567b49c5d04a5f83870795b8c0e2df43a8ce32"
 
 [solve-meta]
   analyzer-name = "dep"
diff --git a/collector/mempool.go b/collector/mempool.go
new file mode 100644
index 0000000..9867c0c
--- /dev/null
+++ b/collector/mempool.go
@@ -0,0 +1,85 @@
+package collector
+
+import (
+	"context"
+	"sync"
+
+	"github.com/ecadlabs/go-tezos"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type MempoolOperationsCollector struct {
+	prometheus.Collector // refers to counter
+
+	counter *prometheus.CounterVec
+	service *tezos.Service
+	chainID string
+	wg      sync.WaitGroup
+	cancel  context.CancelFunc
+}
+
+func (m *MempoolOperationsCollector) listener(ctx context.Context, pool string) {
+	ch := make(chan []*tezos.Operation, 100)
+	defer close(ch)
+
+	go func() {
+		for ops := range ch {
+			for _, op := range ops {
+				for _, elem := range op.Contents {
+					m.counter.WithLabelValues(pool, op.Protocol, elem.OperationElemKind()).Inc()
+				}
+			}
+		}
+	}()
+
+	for {
+		err := m.service.MonitorMempoolOperations(ctx, m.chainID, pool, ch)
+		if err == context.Canceled {
+			return
+		}
+	}
+}
+
+func NewMempoolOperationsCollectorCollector(service *tezos.Service, chainID string, pools []string) *MempoolOperationsCollector {
+	counter := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "tezos_node_mempool_operations_total",
+			Help: "The total number of mempool operations.",
+		},
+		[]string{"pool", "proto", "kind"},
+	)
+
+	c := MempoolOperationsCollector{
+		Collector: counter,
+		counter:   counter,
+		service:   service,
+		chainID:   chainID,
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	c.cancel = cancel
+
+	for _, p := range pools {
+		c.wg.Add(1)
+		go c.listener(ctx, p)
+	}
+
+	return &c
+}
+
+func (m *MempoolOperationsCollector) Shutdown(ctx context.Context) error {
+	m.cancel()
+
+	sem := make(chan struct{})
+	go func() {
+		m.wg.Wait()
+		close(sem)
+	}()
+
+	select {
+	case <-sem:
+		return nil
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+}
diff --git a/collector/network.go b/collector/network.go
index 617537b..66889b7 100644
--- a/collector/network.go
+++ b/collector/network.go
@@ -49,11 +49,13 @@ var (
 		nil,
 		nil)
 
-	mempoolDesc = prometheus.NewDesc(
-		"tezos_node_mempool_operations",
-		"The current number of mempool operations.",
-		[]string{"pool", "proto", "kind"},
-		nil)
+	/*
+		mempoolDesc = prometheus.NewDesc(
+			"tezos_node_mempool_operations",
+			"The current number of mempool operations.",
+			[]string{"pool", "proto", "kind"},
+			nil)
+	*/
 
 	rpcFailedDesc = prometheus.NewDesc(
 		"tezos_rpc_failed",
@@ -70,10 +72,7 @@ type NetworkCollector struct {
 }
 
 // NewNetworkCollector returns a new NetworkCollector.
-func NewNetworkCollector(
-	service *tezos.Service,
-	timeout time.Duration,
-	chainID string) *NetworkCollector {
+func NewNetworkCollector(service *tezos.Service, timeout time.Duration, chainID string) *NetworkCollector {
 	return &NetworkCollector{
 		service: service,
 		timeout: timeout,
@@ -197,6 +196,7 @@ func getPeerStats(ctx context.Context, service *tezos.Service) (map[string]map[s
 	return peerStats, nil
 }
 
+/*
 func getMempoolStats(ctx context.Context, service *tezos.Service, chainID string) (map[string]map[string]map[string]int, error) {
 	buildStats := func(ops []*tezos.Operation) map[string]map[string]int {
 		stats := map[string]map[string]int{}
@@ -240,6 +240,7 @@ func getMempoolStats(ctx context.Context, service *tezos.Service, chainID string
 		"unprocessed":    buildStats(opsFromOpsAlt(ops.Unprocessed)),
 	}, nil
 }
+*/
 
 // Collect implements prometheus.Collector and is called by the Prometheus registry when collecting metrics.
 func (c *NetworkCollector) Collect(ch chan<- prometheus.Metric) {
@@ -300,14 +301,16 @@ func (c *NetworkCollector) Collect(ch chan<- prometheus.Metric) {
 		ch <- prometheus.MustNewConstMetric(bootstrappedDesc, prometheus.GaugeValue, v)
 	}
 
-	mempoolStats, err := getMempoolStats(ctx, &srv, c.chainID)
-	if err == nil {
-		for pool, stats := range mempoolStats {
-			for proto, protoStats := range stats {
-				for kind, count := range protoStats {
-					ch <- prometheus.MustNewConstMetric(mempoolDesc, prometheus.GaugeValue, float64(count), pool, proto, kind)
+	/*
+		mempoolStats, err := getMempoolStats(ctx, &srv, c.chainID)
+		if err == nil {
+			for pool, stats := range mempoolStats {
+				for proto, protoStats := range stats {
+					for kind, count := range protoStats {
+						ch <- prometheus.MustNewConstMetric(mempoolDesc, prometheus.GaugeValue, float64(count), pool, proto, kind)
+					}
 				}
 			}
 		}
-	}
+	*/
 }
diff --git a/main.go b/main.go
index 7d48e69..f2ee2ef 100644
--- a/main.go
+++ b/main.go
@@ -38,6 +38,12 @@ func main() {
 	reg.MustRegister(prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{}))
 	reg.MustRegister(prometheus.NewGoCollector())
 	reg.MustRegister(collector.NewNetworkCollector(service, defaultTimeout, *chainID))
+	reg.MustRegister(collector.NewMempoolOperationsCollectorCollector(service, *chainID, []string{
+		"applied",
+		"branch_refused",
+		"refused",
+		"branch_delayed",
+	}))
 
 	http.Handle("/metrics", promhttp.HandlerFor(reg, promhttp.HandlerOpts{}))
 	if err := http.ListenAndServe(*metricsAddr, nil); err != nil {
diff --git a/vendor/github.com/ecadlabs/go-tezos/client.go b/vendor/github.com/ecadlabs/go-tezos/client.go
index 99e6241..8ab120d 100644
--- a/vendor/github.com/ecadlabs/go-tezos/client.go
+++ b/vendor/github.com/ecadlabs/go-tezos/client.go
@@ -63,6 +63,8 @@ type RPCClient struct {
 	UserAgent string
 	// Optional callback for metrics.
 	RPCStatusCallback func(req *http.Request, status int, duration time.Duration, err error)
+	// Optional callback for metrics.
+	RPCHeaderCallback func(req *http.Request, resp *http.Response, duration time.Duration)
 }
 
 // NewRPCClient returns a new Tezos RPC client.
@@ -133,6 +135,10 @@ func (c *RPCClient) Do(req *http.Request, v interface{}) (err error) {
 	timestamp := time.Now()
 
 	resp, err := c.Client.Do(req)
+	if c.RPCHeaderCallback != nil {
+		duration := time.Since(timestamp)
+		c.RPCHeaderCallback(req, resp, duration)
+	}
 
 	if c.RPCStatusCallback != nil {
 		defer func() {