diff --git a/schema/defs-config.json b/schema/defs-config.json
index 47ad2c6c0..adad2fb3f 100644
--- a/schema/defs-config.json
+++ b/schema/defs-config.json
@@ -75,10 +75,17 @@
             "type": "string"
           }
         },
-        "layers": {
-          "type": "string"
+        "type": {
+          "type": "string",
+          "enum": [
+            "layers"
+          ]
         }
-      }
+      },
+      "required": [
+        "diff_ids",
+        "type"
+      ]
     },
     "history": {
       "type": "object",
diff --git a/schema/fs.go b/schema/fs.go
index 5f4db5d89..fd559a7c3 100644
--- a/schema/fs.go
+++ b/schema/fs.go
@@ -205,7 +205,7 @@ var _escData = map[string]*_escFile{
 	"/config-schema.json": {
 		local:   "config-schema.json",
 		size:    710,
-		modtime: 1466466955,
+		modtime: 1473949379,
 		compressed: `
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 Tdt2A4hjjIoUunPbvUUIrxTUYgBu05/HS/sewaFHZ4vrKWNHcSNMNiOjajwbcxUKfVVPxBczsPXaP7+Y
@@ -217,56 +217,56 @@ l/9nPbhN1oiixPffrmGZ7f1n3Wk307p0d+1S8eDmZvnOzdx8BQAA//964XeexgIAAA==
 
 	"/content-descriptor.json": {
 		local:   "content-descriptor.json",
-		size:    616,
-		modtime: 1466180793,
+		size:    637,
+		modtime: 1473949379,
 		compressed: `
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 `,
 	},
 
 	"/defs-config.json": {
 		local:   "defs-config.json",
-		size:    2154,
-		modtime: 1466467007,
+		size:    2270,
+		modtime: 1475248413,
 		compressed: `
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 `,
 	},
 
 	"/defs-image.json": {
 		local:   "defs-image.json",
-		size:    2528,
-		modtime: 1466438460,
+		size:    2550,
+		modtime: 1473999429,
 		compressed: `
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 `,
 	},
 
 	"/defs.json": {
 		local:   "defs.json",
 		size:    3193,
-		modtime: 1466180793,
+		modtime: 1473949379,
 		compressed: `
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@@ -285,7 +285,7 @@ MrVJbn8cB+ZnN/gbAAD//0JyEpx5DAAA
 	"/image-manifest-schema.json": {
 		local:   "image-manifest-schema.json",
 		size:    1032,
-		modtime: 1466180793,
+		modtime: 1474208561,
 		compressed: `
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@@ -300,7 +300,7 @@ X3p8DwgEAAA=
 	"/manifest-list-schema.json": {
 		local:   "manifest-list-schema.json",
 		size:    1010,
-		modtime: 1466180793,
+		modtime: 1473949379,
 		compressed: `
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