diff --git a/cache/instructioncache/local/localinstructioncache.go b/cache/instructioncache/local/localinstructioncache.go
index bd45e866..7bacb66a 100644
--- a/cache/instructioncache/local/localinstructioncache.go
+++ b/cache/instructioncache/local/localinstructioncache.go
@@ -13,7 +13,6 @@ import (
 )
 
 const cacheKey = "buildkit.instructioncache"
-const contentCacheKey = "buildkit.instructioncache.content"
 
 const mappingBucket = "_contentMapping"
 
diff --git a/client/client_windows.go b/client/client_windows.go
index 637788c2..ab91df7c 100644
--- a/client/client_windows.go
+++ b/client/client_windows.go
@@ -1,7 +1,6 @@
 package client
 
 import (
-	"fmt"
 	"net"
 	"strings"
 	"time"
@@ -14,7 +13,3 @@ func dialer(address string, timeout time.Duration) (net.Conn, error) {
 	address = strings.Replace(address, "/", "\\", 0)
 	return winio.DialPipe(address, &timeout)
 }
-
-func dialAddress(address string) string {
-	return fmt.Sprintf("npipe://%s", address)
-}
diff --git a/client/llb/meta.go b/client/llb/meta.go
index 3f8f8be3..b8f8af96 100644
--- a/client/llb/meta.go
+++ b/client/llb/meta.go
@@ -18,25 +18,17 @@ var (
 func addEnv(key, value string) StateOption {
 	return addEnvf(key, value)
 }
+
 func addEnvf(key, value string, v ...interface{}) StateOption {
 	return func(s State) State {
 		return s.WithValue(keyEnv, getEnv(s).AddOrReplace(key, fmt.Sprintf(value, v...)))
 	}
 }
-func clearEnv() StateOption {
-	return func(s State) State {
-		return s.WithValue(keyEnv, EnvList{})
-	}
-}
-func delEnv(key string) StateOption {
-	return func(s State) State {
-		return s.WithValue(keyEnv, getEnv(s).Delete(key))
-	}
-}
 
 func dir(str string) StateOption {
 	return dirf(str)
 }
+
 func dirf(str string, v ...interface{}) StateOption {
 	return func(s State) State {
 		return s.WithValue(keyDir, fmt.Sprintf(str, v...))
diff --git a/frontend/dockerfile/dockerfile2llb/convert.go b/frontend/dockerfile/dockerfile2llb/convert.go
index 6a2755d6..b29de289 100644
--- a/frontend/dockerfile/dockerfile2llb/convert.go
+++ b/frontend/dockerfile/dockerfile2llb/convert.go
@@ -249,6 +249,8 @@ func dispatch(d *dispatchState, cmd instructions.Command, opt dispatchOpt) error
 
 	var err error
 	switch c := cmd.(type) {
+	case *instructions.MaintainerCommand:
+		err = dispatchMaintainer(d, c)
 	case *instructions.EnvCommand:
 		err = dispatchEnv(d, c, true)
 	case *instructions.RunCommand:
@@ -439,7 +441,7 @@ func dispatchCopy(d *dispatchState, c instructions.SourcesAndDest, sourceState l
 	return commitToHistory(&d.image, commitMessage.String(), true, &d.state)
 }
 
-func dispatchMaintainer(d *dispatchState, c instructions.MaintainerCommand) error {
+func dispatchMaintainer(d *dispatchState, c *instructions.MaintainerCommand) error {
 	d.image.Author = c.Maintainer
 	return commitToHistory(&d.image, fmt.Sprintf("MAINTAINER %v", c.Maintainer), false, nil)
 }
diff --git a/gometalinter.json b/gometalinter.json
index 2b3efa7d..e79b3f10 100644
--- a/gometalinter.json
+++ b/gometalinter.json
@@ -1,12 +1,13 @@
 {
   "Vendor": true,
   "Deadline": "8m",
-  "Exclude": ["solver/pb/ops.pb.go", "api/services/control/control.pb.go"],
+  "Exclude": [".*.pb.go"],
   "DisableAll": true,
   "Enable": [
     "gofmt",
     "goimports",
     "ineffassign",
-    "vet"
+    "vet",
+    "deadcode"
   ]
 }
diff --git a/session/grpchijack/dial.go b/session/grpchijack/dial.go
index 561cf58e..151ab549 100644
--- a/session/grpchijack/dial.go
+++ b/session/grpchijack/dial.go
@@ -14,12 +14,6 @@ import (
 	"google.golang.org/grpc/metadata"
 )
 
-var bufPool = sync.Pool{
-	New: func() interface{} {
-		return make([]byte, 32*1<<10)
-	},
-}
-
 func Dialer(api controlapi.ControlClient) session.Dialer {
 	return func(ctx context.Context, proto string, meta map[string][]string) (net.Conn, error) {
 
diff --git a/solver/llbbridge.go b/solver/llbbridge.go
index eb12ee76..8fac42cf 100644
--- a/solver/llbbridge.go
+++ b/solver/llbbridge.go
@@ -10,7 +10,6 @@ import (
 	"github.com/moby/buildkit/frontend"
 	"github.com/moby/buildkit/util/tracing"
 	"github.com/moby/buildkit/worker"
-	digest "github.com/opencontainers/go-digest"
 	"github.com/pkg/errors"
 )
 
@@ -22,10 +21,6 @@ type llbBridge struct {
 	worker.Worker
 }
 
-type resolveImageConfig interface {
-	ResolveImageConfig(ctx context.Context, ref string) (digest.Digest, []byte, error)
-}
-
 func (s *llbBridge) Solve(ctx context.Context, req frontend.SolveRequest) (cache.ImmutableRef, map[string][]byte, error) {
 	var f frontend.Frontend
 	if req.Frontend != "" {
diff --git a/solver/load.go b/solver/load.go
index 1914d073..d03f274d 100644
--- a/solver/load.go
+++ b/solver/load.go
@@ -22,11 +22,6 @@ func newVertex(dgst digest.Digest, op *pb.Op, opMeta *pb.OpMetadata, load func(d
 	return vtx, nil
 }
 
-func toInternalVertex(v Vertex) *vertex {
-	cache := make(map[digest.Digest]*vertex)
-	return loadInternalVertexHelper(v, cache)
-}
-
 func loadInternalVertexHelper(v Vertex, cache map[digest.Digest]*vertex) *vertex {
 	if v, ok := cache[v.Digest()]; ok {
 		return v
diff --git a/source/containerimage/pull.go b/source/containerimage/pull.go
index ee011147..98b125de 100644
--- a/source/containerimage/pull.go
+++ b/source/containerimage/pull.go
@@ -42,11 +42,6 @@ type SourceOpt struct {
 	CacheAccessor  cache.Accessor
 }
 
-type resolveRecord struct {
-	desc ocispec.Descriptor
-	ts   time.Time
-}
-
 type imageSource struct {
 	SourceOpt
 	g flightcontrol.Group