diff --git a/context.go b/context.go
index 5e629fc..8529f8c 100644
--- a/context.go
+++ b/context.go
@@ -1,9 +1,8 @@
 package maps
 
 import (
+	"context"
 	"net/http"
-
-	"golang.org/x/net/context"
 )
 
 type contextKey int
diff --git a/directions.go b/directions.go
index 1c04a3e..3c8a972 100644
--- a/directions.go
+++ b/directions.go
@@ -1,12 +1,11 @@
 package maps
 
 import (
+	"context"
 	"fmt"
 	"net/url"
 	"strings"
 	"time"
-
-	"golang.org/x/net/context"
 )
 
 const (
diff --git a/distance.go b/distance.go
index 57aec55..45a0714 100644
--- a/distance.go
+++ b/distance.go
@@ -1,11 +1,10 @@
 package maps
 
 import (
+	"context"
 	"fmt"
 	"net/url"
 	"time"
-
-	"golang.org/x/net/context"
 )
 
 // DistanceMatrix requests travel distance and time for a matrix of origins and destinations.
diff --git a/elevation.go b/elevation.go
index 50489d8..83c25b1 100644
--- a/elevation.go
+++ b/elevation.go
@@ -1,10 +1,9 @@
 package maps
 
 import (
+	"context"
 	"fmt"
 	"net/url"
-
-	"golang.org/x/net/context"
 )
 
 // Elevation requests elevation data for a series of locations.
diff --git a/geocode.go b/geocode.go
index a1d5e59..34bce74 100644
--- a/geocode.go
+++ b/geocode.go
@@ -1,11 +1,10 @@
 package maps
 
 import (
+	"context"
 	"fmt"
 	"net/url"
 	"strings"
-
-	"golang.org/x/net/context"
 )
 
 const (
diff --git a/maps.go b/maps.go
index e787466..b020447 100644
--- a/maps.go
+++ b/maps.go
@@ -1,6 +1,7 @@
 package maps
 
 import (
+	"context"
 	"crypto/hmac"
 	"crypto/sha1"
 	"encoding/base64"
@@ -8,8 +9,6 @@ import (
 	"fmt"
 	"net/http"
 	"strings"
-
-	"golang.org/x/net/context"
 )
 
 const (
diff --git a/maps_test.go b/maps_test.go
index ee44709..6682295 100644
--- a/maps_test.go
+++ b/maps_test.go
@@ -1,22 +1,25 @@
 package maps
 
 import (
-	"flag"
 	"image/color"
+	"log"
 	"net/http"
+	"os"
 	"testing"
 	"time"
 )
 
 var (
-	apiKey = flag.String("apiKey", "", "Google Maps API key")
-
-	ctx  = NewContext("", &http.Client{})
-	wctx = NewWorkContext("clientID", "privKey", &http.Client{})
+	apiKey string
+	ctx    = NewContext("", &http.Client{})
+	wctx   = NewWorkContext("clientID", "privKey", &http.Client{})
 )
 
 func init() {
-	flag.Parse()
+	apiKey = os.Getenv("API_KEY")
+	if apiKey == "" {
+		log.Fatal("API_KEY must be provided")
+	}
 }
 
 func TestDirections(t *testing.T) {
@@ -200,7 +203,7 @@ func TestSnapToRoads(t *testing.T) {
 		t.Errorf("unexpected error, got %v, want %v", err, ErrNoAPIKey)
 	}
 
-	keyCtx := NewContext(*apiKey, &http.Client{})
+	keyCtx := NewContext(apiKey, &http.Client{})
 	r, err := SnapToRoads(keyCtx, path, opts)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
diff --git a/roads.go b/roads.go
index 0f163f8..a6846e9 100644
--- a/roads.go
+++ b/roads.go
@@ -1,10 +1,9 @@
 package maps
 
 import (
+	"context"
 	"errors"
 	"net/url"
-
-	"code.google.com/p/go.net/context"
 )
 
 const roadsAPIBaseURL = "https://roads.googleapis.com/v1/"
diff --git a/static.go b/static.go
index 2483978..19f08ba 100644
--- a/static.go
+++ b/static.go
@@ -1,14 +1,13 @@
 package maps
 
 import (
+	"context"
 	"fmt"
 	"image/color"
 	"io"
 	"net/http"
 	"net/url"
 	"strings"
-
-	"golang.org/x/net/context"
 )
 
 const (
diff --git a/streetview.go b/streetview.go
index 7673cb6..f655890 100644
--- a/streetview.go
+++ b/streetview.go
@@ -1,12 +1,11 @@
 package maps
 
 import (
+	"context"
 	"fmt"
 	"io"
 	"net/http"
 	"net/url"
-
-	"golang.org/x/net/context"
 )
 
 // StreetView requests a static StreetView image of the requested size.
diff --git a/timezone.go b/timezone.go
index f698080..cb74a55 100644
--- a/timezone.go
+++ b/timezone.go
@@ -1,11 +1,10 @@
 package maps
 
 import (
+	"context"
 	"fmt"
 	"net/url"
 	"time"
-
-	"golang.org/x/net/context"
 )
 
 // TimeZone requests time zone information about a location.