diff --git a/config.go b/config.go
index 269e0cbe5..19f423e2b 100644
--- a/config.go
+++ b/config.go
@@ -1,5 +1,9 @@
 package specs
 
+import (
+	"encoding/json"
+)
+
 // Spec is the base configuration for the container.  It specifies platform
 // independent configuration.
 type Spec struct {
@@ -21,8 +25,8 @@ type Spec struct {
 type Process struct {
 	// Terminal creates an interactive terminal for the container.
 	Terminal bool `json:"terminal"`
-	// User specifies user information for the process.
-	User User `json:"user"`
+	// User specifies user information for the process. It is a platform-specific structure.
+	User json.RawMessage `json:"user"`
 	// Args specifies the binary and arguments for the application to execute.
 	Args []string `json:"args"`
 	// Env populates the process environment for the process.
diff --git a/config_linux.go b/linux/config.go
similarity index 92%
rename from config_linux.go
rename to linux/config.go
index 4bfb78325..5338d7c9a 100644
--- a/config_linux.go
+++ b/linux/config.go
@@ -1,10 +1,12 @@
-// +build linux
+package linux
 
-package specs
+import (
+	"github.com/opencontainers/specs"
+)
 
 // LinuxSpec is the full specification for linux containers.
 type LinuxSpec struct {
-	Spec
+	specs.Spec
 	// Linux is platform specific configuration for linux based containers.
 	Linux Linux `json:"linux"`
 }
diff --git a/config-linux.md b/linux/config.md
similarity index 100%
rename from config-linux.md
rename to linux/config.md
diff --git a/runtime_config_linux.go b/linux/runtime-config.go
similarity index 98%
rename from runtime_config_linux.go
rename to linux/runtime-config.go
index 7ddffdd03..450338546 100644
--- a/runtime_config_linux.go
+++ b/linux/runtime-config.go
@@ -1,13 +1,17 @@
-package specs
+package linux
 
-import "os"
+import (
+	"os"
+
+	"github.com/opencontainers/specs"
+)
 
 // LinuxStateDirectory holds the container's state information
 const LinuxStateDirectory = "/run/opencontainer/containers"
 
 // LinuxRuntimeSpec is the full specification for linux containers.
 type LinuxRuntimeSpec struct {
-	RuntimeSpec
+	specs.RuntimeSpec
 	// LinuxRuntime is platform specific configuration for linux based containers.
 	Linux LinuxRuntime `json:"linux"`
 }
diff --git a/runtime-config-linux.md b/linux/runtime-config.md
similarity index 100%
rename from runtime-config-linux.md
rename to linux/runtime-config.md
diff --git a/runtime-linux.md b/linux/runtime.md
similarity index 100%
rename from runtime-linux.md
rename to linux/runtime.md