@@ -200,6 +200,7 @@ func (builder *Builder) Build(dockerfile io.Reader, stdout io.Writer) (*Image, e

 		image, base   *Image

 		config        *Config

 		maintainer    string

+		env           map[string]string   = make(map[string]string)

 		tmpContainers map[string]struct{} = make(map[string]struct{})

 		tmpImages     map[string]struct{} = make(map[string]struct{})

 	)

@@ -270,6 +271,10 @@ func (builder *Builder) Build(dockerfile io.Reader, stdout io.Writer) (*Image, e

 				return nil, err

 			}

+			for key, value := range env {

+				config.Env = append(config.Env, fmt.Sprintf("%s=%s", key, value))

+			}

+

 			if cache, err := builder.getCachedImage(image, config); err != nil {

 				return nil, err

 			} else if cache != nil {

@@ -278,11 +283,21 @@ func (builder *Builder) Build(dockerfile io.Reader, stdout io.Writer) (*Image, e

 				break

 			}

+			Debugf("Env -----> %v ------ %v\n", config.Env, env)

+

 			// Create the container and start it

 			c, err := builder.Create(config)

 			if err != nil {

 				return nil, err

 			}

+

+			if os.Getenv("DEBUG") != "" {

+				out, _ := c.StdoutPipe()

+				err2, _ := c.StderrPipe()

+				go io.Copy(os.Stdout, out)

+				go io.Copy(os.Stdout, err2)

+			}

+

 			if err := c.Start(); err != nil {

 				return nil, err

 			}

@@ -306,6 +321,21 @@ func (builder *Builder) Build(dockerfile io.Reader, stdout io.Writer) (*Image, e

 			image = base

 			break

+		case "env":

+			tmp := strings.SplitN(arguments, " ", 2)

+			if len(tmp) != 2 {

+				return nil, fmt.Errorf("Invalid ENV format")

+			}

+			key := strings.Trim(tmp[0], " ")

+			value := strings.Trim(tmp[1], " ")

+			fmt.Fprintf(stdout, "ENV %s %s\n", key, value)

+			env[key] = value

+			if image != nil {

+				fmt.Fprintf(stdout, "===> %s\n", image.ShortId())

+			} else {

+				fmt.Fprintf(stdout, "===> <nil>\n")

+			}

+			break

 		case "cmd":

 			fmt.Fprintf(stdout, "CMD %s\n", arguments)