diff --git a/go.mod b/go.mod
index 795e4eb39..66f4a3b59 100644
--- a/go.mod
+++ b/go.mod
@@ -80,6 +80,7 @@ require (
 	github.com/onsi/ginkgo v1.9.0 // indirect
 	github.com/onsi/gomega v1.6.0 // indirect
 	github.com/opentracing/opentracing-go v1.1.0
+	github.com/otiai10/copy v1.0.2
 	github.com/polydawn/refmt v0.0.0-20190809202753-05966cbd336a
 	github.com/smartystreets/assertions v1.0.1 // indirect
 	github.com/smartystreets/goconvey v0.0.0-20190731233626-505e41936337 // indirect
diff --git a/go.sum b/go.sum
index e06831208..937485ffa 100644
--- a/go.sum
+++ b/go.sum
@@ -510,6 +510,11 @@ github.com/opentracing/opentracing-go v1.0.2/go.mod h1:UkNAQd3GIcIGf0SeVgPpRdFSt
 github.com/opentracing/opentracing-go v1.1.0 h1:pWlfV3Bxv7k65HYwkikxat0+s3pV4bsqf19k25Ur8rU=
 github.com/opentracing/opentracing-go v1.1.0/go.mod h1:UkNAQd3GIcIGf0SeVgPpRdFStlNbqXla1AfSYxPUl2o=
 github.com/openzipkin/zipkin-go v0.1.6/go.mod h1:QgAqvLzwWbR/WpD4A3cGpPtJrZXNIiJc5AZX7/PBEpw=
+github.com/otiai10/copy v1.0.2 h1:DDNipYy6RkIkjMwy+AWzgKiNTyj2RUI9yEMeETEpVyc=
+github.com/otiai10/copy v1.0.2/go.mod h1:c7RpqBkwMom4bYTSkLSym4VSJz/XtncWRAj/J4PEIMY=
+github.com/otiai10/curr v0.0.0-20150429015615-9b4961190c95/go.mod h1:9qAhocn7zKJG+0mI8eUu6xqkFDYS2kb2saOteoSB3cE=
+github.com/otiai10/mint v1.3.0 h1:Ady6MKVezQwHBkGzLFbrsywyp09Ah7rkmfjV3Bcr5uc=
+github.com/otiai10/mint v1.3.0/go.mod h1:F5AjcsTsWUqX+Na9fpHb52P8pcRX2CI6A3ctIT91xUo=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/pierrec/lz4 v2.0.5+incompatible/go.mod h1:pdkljMzZIN41W+lC3N2tnIh5sFi+IEE17M5jbnwPHcY=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
diff --git a/lib/sectorbuilder/sectorbuilder.go b/lib/sectorbuilder/sectorbuilder.go
index 84d06cccf..7a5d744ab 100644
--- a/lib/sectorbuilder/sectorbuilder.go
+++ b/lib/sectorbuilder/sectorbuilder.go
@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"path/filepath"
 	"strconv"
 	"sync"
 	"sync/atomic"
@@ -12,6 +11,7 @@ import (
 	sectorbuilder "github.com/filecoin-project/filecoin-ffi"
 	"github.com/ipfs/go-datastore"
 	logging "github.com/ipfs/go-log"
+	dcopy "github.com/otiai10/copy"
 	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/lotus/build"
@@ -688,15 +688,15 @@ func fallbackPostChallengeCount(sectors uint64) uint64 {
 }
 
 func (sb *SectorBuilder) ImportFrom(osb *SectorBuilder) error {
-	if err := copyAllFiles(osb.cacheDir, sb.cacheDir); err != nil {
+	if err := dcopy.Copy(osb.cacheDir, sb.cacheDir); err != nil {
 		return err
 	}
 
-	if err := copyAllFiles(osb.sealedDir, sb.sealedDir); err != nil {
+	if err := dcopy.Copy(osb.sealedDir, sb.sealedDir); err != nil {
 		return err
 	}
 
-	if err := copyAllFiles(osb.stagedDir, sb.stagedDir); err != nil {
+	if err := dcopy.Copy(osb.stagedDir, sb.stagedDir); err != nil {
 		return err
 	}
 
@@ -722,66 +722,3 @@ func (sb *SectorBuilder) SetLastSectorID(id uint64) error {
 	sb.lastID = id
 	return nil
 }
-
-func copyAllFiles(from, to string) error {
-	dir, err := os.Open(from)
-	if err != nil {
-		return err
-	}
-
-	names, err := dir.Readdirnames(0)
-	if err != nil {
-		return xerrors.Errorf("failed to list items in dir: %w", err)
-	}
-	for _, n := range names {
-		if err := copyFile(filepath.Join(from, n), filepath.Join(to, n)); err != nil {
-			return xerrors.Errorf("copying file failed: %w", err)
-		}
-	}
-
-	return nil
-}
-
-func copyFile(from, to string) error {
-	st, err := os.Stat(to)
-	if err != nil {
-		if !os.IsNotExist(err) {
-			return xerrors.Errorf("stat of target file returned unexpected error: %w", err)
-		}
-	}
-
-	if st != nil {
-		log.Warn("destination file %q already exists! skipping copy...", to)
-		return nil
-	}
-
-	dst, err := os.Create(to)
-	if err != nil {
-		return xerrors.Errorf("failed to create target file: %w", err)
-	}
-	defer dst.Close()
-
-	fromst, err := os.Stat(from)
-	if err != nil {
-		return err
-	}
-
-	if fromst.IsDir() {
-		if err := os.Mkdir(to, 0755); err != nil {
-			return xerrors.Errorf("making target directory failed: %w", err)
-		}
-		return copyAllFiles(from, to)
-	}
-
-	src, err := os.Open(from)
-	if err != nil {
-		return xerrors.Errorf("failed to open source file: %w", err)
-	}
-	defer src.Close()
-
-	if _, err := io.Copy(dst, src); err != nil {
-		return xerrors.Errorf("copy failed: %w", err)
-	}
-
-	return nil
-}