diff --git a/build_config.rb.lock b/build_config.rb.lock
index b20e30f..2f55416 100644
--- a/build_config.rb.lock
+++ b/build_config.rb.lock
@@ -52,8 +52,8 @@ builds:
     https://github.com/buty4649/mruby-yyjson.git:
       url: https://github.com/buty4649/mruby-yyjson.git
       branch: main
-      commit: 8f46e5c1c0e5c1dae8c45de5e7db059112cb3641
-      version: 1.2.0
+      commit: 3ecdfacf5a1bacee5d28292dbaf45b5febc1fbbf
+      version: 1.4.0
   linux-amd64:
     https://github.com/fastly/mruby-optparse.git:
       url: https://github.com/fastly/mruby-optparse.git
@@ -98,8 +98,8 @@ builds:
     https://github.com/buty4649/mruby-yyjson.git:
       url: https://github.com/buty4649/mruby-yyjson.git
       branch: main
-      commit: 8f46e5c1c0e5c1dae8c45de5e7db059112cb3641
-      version: 1.2.0
+      commit: 3ecdfacf5a1bacee5d28292dbaf45b5febc1fbbf
+      version: 1.4.0
   linux-arm64:
     https://github.com/fastly/mruby-optparse.git:
       url: https://github.com/fastly/mruby-optparse.git
@@ -144,8 +144,8 @@ builds:
     https://github.com/buty4649/mruby-yyjson.git:
       url: https://github.com/buty4649/mruby-yyjson.git
       branch: main
-      commit: 8f46e5c1c0e5c1dae8c45de5e7db059112cb3641
-      version: 1.2.0
+      commit: 3ecdfacf5a1bacee5d28292dbaf45b5febc1fbbf
+      version: 1.4.0
   darwin-amd64:
     https://github.com/fastly/mruby-optparse.git:
       url: https://github.com/fastly/mruby-optparse.git
@@ -226,8 +226,8 @@ builds:
     https://github.com/buty4649/mruby-yyjson.git:
       url: https://github.com/buty4649/mruby-yyjson.git
       branch: main
-      commit: 8f46e5c1c0e5c1dae8c45de5e7db059112cb3641
-      version: 1.2.0
+      commit: 3ecdfacf5a1bacee5d28292dbaf45b5febc1fbbf
+      version: 1.4.0
   windows-amd64:
     https://github.com/fastly/mruby-optparse.git:
       url: https://github.com/fastly/mruby-optparse.git
@@ -272,5 +272,5 @@ builds:
     https://github.com/buty4649/mruby-yyjson.git:
       url: https://github.com/buty4649/mruby-yyjson.git
       branch: main
-      commit: 8f46e5c1c0e5c1dae8c45de5e7db059112cb3641
-      version: 1.2.0
+      commit: 3ecdfacf5a1bacee5d28292dbaf45b5febc1fbbf
+      version: 1.4.0
diff --git a/mruby b/mruby
index 5072358..7c7ee5c 160000
--- a/mruby
+++ b/mruby
@@ -1 +1 @@
-Subproject commit 5072358276a45453e8cc9fe4d0b515f2e9a3e15d
+Subproject commit 7c7ee5c244d48a8473d67825dcd2528c769706ba