diff --git a/promql/engine_test.go b/promql/engine_test.go
index 61786950e..c3bec1315 100644
--- a/promql/engine_test.go
+++ b/promql/engine_test.go
@@ -8,10 +8,6 @@ import (
 	"golang.org/x/net/context"
 )
 
-var noop = testStmt(func(context.Context) error {
-	return nil
-})
-
 func TestQueryConcurrency(t *testing.T) {
 	engine := NewEngine(nil, nil)
 	defer engine.Stop()
diff --git a/promql/parse.go b/promql/parse.go
index c91df6fb3..5cb1fef68 100644
--- a/promql/parse.go
+++ b/promql/parse.go
@@ -925,8 +925,6 @@ func (p *parser) offset() time.Duration {
 //		[<metric_identifier>] <label_matchers>
 //
 func (p *parser) vectorSelector(name string) *VectorSelector {
-	const ctx = "metric selector"
-
 	var matchers metric.LabelMatchers
 	// Parse label matching if any.
 	if t := p.peek(); t.typ == itemLeftBrace {
diff --git a/retrieval/discovery/dns.go b/retrieval/discovery/dns.go
index 7c744f8c0..cd1c01bf6 100644
--- a/retrieval/discovery/dns.go
+++ b/retrieval/discovery/dns.go
@@ -36,7 +36,6 @@ const (
 
 	// Constants for instrumentation.
 	namespace = "prometheus"
-	interval  = "interval"
 )
 
 var (
diff --git a/retrieval/discovery/nerve.go b/retrieval/discovery/nerve.go
index f99c9d61f..8422ce38b 100644
--- a/retrieval/discovery/nerve.go
+++ b/retrieval/discovery/nerve.go
@@ -28,8 +28,6 @@ import (
 )
 
 const (
-	nerveNodePrefix = "member_"
-
 	nerveLabelPrefix         = model.MetaLabelPrefix + "nerve_"
 	nervePathLabel           = nerveLabelPrefix + "path"
 	nerveEndpointLabelPrefix = nerveLabelPrefix + "endpoint"
diff --git a/retrieval/discovery/serverset.go b/retrieval/discovery/serverset.go
index 5a13af63c..48748518f 100644
--- a/retrieval/discovery/serverset.go
+++ b/retrieval/discovery/serverset.go
@@ -30,8 +30,6 @@ import (
 )
 
 const (
-	serversetNodePrefix = "member_"
-
 	serversetLabelPrefix         = model.MetaLabelPrefix + "serverset_"
 	serversetStatusLabel         = serversetLabelPrefix + "status"
 	serversetPathLabel           = serversetLabelPrefix + "path"
diff --git a/retrieval/scrape.go b/retrieval/scrape.go
index c2ff4496e..925d8151f 100644
--- a/retrieval/scrape.go
+++ b/retrieval/scrape.go
@@ -14,7 +14,6 @@
 package retrieval
 
 import (
-	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -37,9 +36,6 @@ const (
 	scrapeHealthMetricName   = "up"
 	scrapeDurationMetricName = "scrape_duration_seconds"
 
-	// Capacity of the channel to buffer samples during ingestion.
-	ingestedSamplesCap = 256
-
 	// Constants for instrumentation.
 	namespace = "prometheus"
 	interval  = "interval"
@@ -47,8 +43,6 @@ const (
 )
 
 var (
-	errSkippedScrape = errors.New("scrape skipped due to throttled ingestion")
-
 	targetIntervalLength = prometheus.NewSummaryVec(
 		prometheus.SummaryOpts{
 			Namespace:  namespace,
diff --git a/storage/remote/opentsdb/client.go b/storage/remote/opentsdb/client.go
index dcf56ecc5..46575313f 100644
--- a/storage/remote/opentsdb/client.go
+++ b/storage/remote/opentsdb/client.go
@@ -21,7 +21,6 @@ import (
 	"math"
 	"net/http"
 	"net/url"
-	"regexp"
 	"time"
 
 	"github.com/prometheus/common/log"
@@ -36,10 +35,6 @@ const (
 	contentTypeJSON = "application/json"
 )
 
-var (
-	illegalCharsRE = regexp.MustCompile(`[^a-zA-Z0-9_\-./]`)
-)
-
 // Client allows sending batches of Prometheus samples to OpenTSDB.
 type Client struct {
 	url        string