diff --git a/libs/core/pxt.json b/libs/core/pxt.json
index ea2734b6..fcb72a91 100644
--- a/libs/core/pxt.json
+++ b/libs/core/pxt.json
@@ -121,14 +121,12 @@
                     "advertising_timeout": 0,
                     "tx_power": 6,
                     "dfu_service": 1,
-                    "event_service": 0,
-                    "device_info_service": 0
+                    "event_service": 1,
+                    "device_info_service": 1
                 },
-                "stack_size": 1280,
+                "stack_size": 2048,
                 "gatt_table_size": "0x600",
-                "panic_on_heap_full": 0,
-                "debug": 0,
-                "heap_debug": 0
+                "sram_end": "0x20008000"
             }
         },
         "userConfigs": [
diff --git a/pxtarget.json b/pxtarget.json
index 2138946f..13ba1805 100644
--- a/pxtarget.json
+++ b/pxtarget.json
@@ -109,10 +109,10 @@
         "useNewFunctions": true
     },
     "compileService": {
-        "yottaTarget": "calliope-mini-classic-gcc@https://github.com/calliope-mini/target-calliope-mini-classic-gcc#v1.2.0-yotta",
+        "yottaTarget": "calliope-mini-classic-gcc@https://github.com/calliope-mini/target-calliope-mini-classic-gcc#v1.2.0-yotta-32kb",
         "yottaCorePackage": "microbit",
         "githubCorePackage": "calliope-mini/microbit",
-        "gittag": "v2.2.0-rc6-calliope.rc3-iss0.3",
+        "gittag": "v2.2.0-rc6-calliope.rc4-32kb",
         "serviceId": "calliope",
         "dockerImage": "pext/yotta:latest"
     },