diff --git a/common/interpreter/wawaka_wasm/README.md b/common/interpreter/wawaka_wasm/README.md
index 5fa32786..91855386 100644
--- a/common/interpreter/wawaka_wasm/README.md
+++ b/common/interpreter/wawaka_wasm/README.md
@@ -30,8 +30,8 @@ enclave with Wawaka enabled, you will need to do the following:
 There are many toolchains that could be used to build a WASM code. By default, Wawaka contracts are
 compiled with the compilers provided by [WASI SDK](https://github.com/WebAssembly/wasi-sdk). To use
 WASI SDK, download and install the appropriate package file from
-https://github.com/WebAssembly/wasi-sdk/releases (we have verified that release wasi-sdk-12 works
-with WAMR version WAMR-1.1.2).
+https://github.com/WebAssembly/wasi-sdk/releases (we have verified that release wasi-sdk-21 works
+with WAMR version WAMR-1.3).
 
 ```bash
 wget -q -P /tmp https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-12/wasi-sdk_12.0_amd64.deb
@@ -46,14 +46,14 @@ SDK would be installed in the directory `/opt/wasi-sdk`.
 If wawaka is configured as the contract interpreter, the libraries implementing the WASM interpreter
 will be built for use with Intel SGX. The source for the WAMR interpreter is
 included as a submodule in the interpreters/ folder, and will
-always point to the latest tagged commit that we have validated: `WAMR-1.1.2`.
+always point to the latest tagged commit that we have validated: `WAMR-1.3`.
 If the PDO parent repo was not cloned with the `--recurse-submodules` flag,
 you will have to explictly pull the submodule source.
 
 ```
 cd ${PDO_SOURCE_ROOT}/interpreters/wasm-micro-runtime
 git submodule update --init
-git checkout WAMR-1.1.2 # optional
+git checkout WAMR-1.3 # optional
 ```
 
 The WAMR API is built during the Wawaka build, so no additional
diff --git a/contracts/wawaka/common/Util.cpp b/contracts/wawaka/common/Util.cpp
index 175e7b02..5807cae5 100644
--- a/contracts/wawaka/common/Util.cpp
+++ b/contracts/wawaka/common/Util.cpp
@@ -18,12 +18,20 @@
 
 #include "Types.h"
 #include "Util.h"
+#include "WasmExtensions.h"
 
 #ifdef USE_WASI_SDK
 #include <new>
 
-// this function does not appear to be defined in the wasi-sdk
-// lib c++. we need
+// -----------------------------------------------------------------
+// these functions do not appear to be defined in the wasi-sdk
+// lib c++. an error is generally raised about the failure to link
+// an import function. for ones with obvious implements like standard
+// new and delete, we provide viable implementation. for others that
+// are not supported, a message will be generated and the application
+// will abort.
+// -----------------------------------------------------------------
+
 std::new_handler std::get_new_handler() _NOEXCEPT
 {
     return NULL;
@@ -39,11 +47,32 @@ void * operator new[](size_t sz) throw(std::bad_alloc)
     return malloc(sz);
 }
 
+void * operator new(size_t sz, std::align_val_t v)
+{
+    CONTRACT_SAFE_LOG(4, "attempt to invoke unsupported aligned allocation");
+    std::abort();
+}
+
 void operator delete(void *ptr) _NOEXCEPT
 {
     free(ptr);
 }
 
+void operator delete(void *ptr, std::align_val_t) _NOEXCEPT
+{
+    CONTRACT_SAFE_LOG(4, "attempt to invoke unsupported aligned deallocation");
+    std::abort();
+}
+
+#include <stdio.h>
+int vfprintf(FILE *__restrict, const char *__restrict, __isoc_va_list)
+{
+    CONTRACT_SAFE_LOG(4, "attempt to invoke unsupported vfprintf");
+    std::abort();
+
+    return -1;
+}
+
 #endif
 
 /* ----------------------------------------------------------------- *
diff --git a/docker/pdo_base.dockerfile b/docker/pdo_base.dockerfile
index 0abac789..6ecf456e 100644
--- a/docker/pdo_base.dockerfile
+++ b/docker/pdo_base.dockerfile
@@ -68,7 +68,8 @@ RUN apt-get update \
 # -----------------------------------------------------------------
 # Install WASI toolkit
 # -----------------------------------------------------------------
-ARG WASI_VERSION=12
+##ARG WASI_VERSION=12
+ARG WASI_VERSION=21
 ARG WASI_PACKAGE="wasi-sdk_${WASI_VERSION}.0_amd64.deb"
 
 WORKDIR /tmp