diff --git a/.123trigger b/.123trigger
index 22cd26f7..64aa348b 100644
--- a/.123trigger
+++ b/.123trigger
@@ -1,7 +1,6 @@
-5
+6
 3.2.2
 3.2.3
 3.2.4
 4.0.2
-
-4.1.2
\ No newline at end of file
+4.1.2
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3a76fa17..4d35fd1f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@ Contributed:
 Changes:
 
 - Adjust tests to align with JS coding standards
+- Allow for optional build with Rust stable bootstrap
 
 
 ## 4.1.2 Jul 9, 2021
diff --git a/scripts/build-wasm.sh b/scripts/build-wasm.sh
index 1cd6e99c..711c41d2 100755
--- a/scripts/build-wasm.sh
+++ b/scripts/build-wasm.sh
@@ -5,8 +5,7 @@
 
 set -e
 
-# also change in install-build-deps
-RUST_VER=nightly-2020-10-25
+source ../scripts/rust-version.sh
 
 WSM=bytes/wasm_bg.wasm
 OPT=bytes/wasm_opt.wasm
@@ -15,17 +14,18 @@ ASM=wasm-crypto-asmjs/build/cjs/data.js
 # build new via wasm-pack
 echo "*** Building Rust sources"
 cd wasm-crypto
-rustup run $RUST_VER xargo build --target wasm32-unknown-unknown --release
-# rustup run $RUST_VER cargo build --target wasm32-unknown-unknown --release -Z build-std=std,panic_abort
+if [ "$RUST_VER" == "stable" ]; then
+  RUSTC_BOOTSTRAP=1 cargo build --target wasm32-unknown-unknown --release -Z build-std=std,panic_abort
+else
+  rustup run $RUST_VER xargo build --target wasm32-unknown-unknown --release
+fi
 cd ..
 
 echo "*** Converting to WASM"
 ../bindgen/wasm-bindgen wasm-crypto/target/wasm32-unknown-unknown/release/wasm.wasm --out-dir bytes --target web
-# wasm-pack build --release --scope polkadot --target web
 
 # optimise
 echo "*** Optimising WASM output"
-# ../../wabt/bin/wasm-strip $WSM
 ../binaryen/bin/wasm-opt $WSM -Os -o $OPT
 
 # convert wasm to base64 structure
diff --git a/scripts/install-build-deps.sh b/scripts/install-build-deps.sh
index aa5c31be..2b966e36 100755
--- a/scripts/install-build-deps.sh
+++ b/scripts/install-build-deps.sh
@@ -5,8 +5,7 @@
 
 set -e
 
-# also change in build-package
-RUST_VER=nightly-2020-10-25
+source ./scripts/rust-version.sh
 
 BINARYEN_REPO=https://github.com/WebAssembly/binaryen
 BINARYEN_VER=version_97
@@ -24,7 +23,10 @@ unamestr=`uname`
 
 # toolchain with rust-src (for panic overrdides) and the right wasm32 toolchain
 rustup toolchain install $RUST_VER -c rust-src -t wasm32-unknown-unknown
-cargo install xargo
+
+if [ "$RUST_VER" != "stable" ]; then
+  cargo install xargo
+fi
 
 if [[ "$unamestr" == 'Linux' ]]; then
   echo "*** Detected Linux"
diff --git a/scripts/pack-wasm-base.cjs b/scripts/pack-wasm-base.cjs
index a610df76..0a82a745 100755
--- a/scripts/pack-wasm-base.cjs
+++ b/scripts/pack-wasm-base.cjs
@@ -5,39 +5,20 @@ const fflate = require('fflate/node');
 const fs = require('fs');
 const { formatNumber } = require('@polkadot/util');
 
-// const A_NAME = 'wasm-crypto-asmjs';
 const W_NAME = 'wasm-crypto-wasm';
 
-function hdr (package) {
-  return `// Copyright 2019-2021 @polkadot/${package} authors & contributors
+const data = fs.readFileSync('./bytes/wasm_opt.wasm');
+const compressed = Buffer.from(fflate.zlibSync(data, { level: 9 }));
+
+console.log(`*** Compressed WASM: ${formatNumber(data.length)} -> ${formatNumber(compressed.length)} (${(100 * compressed.length / data.length).toFixed(2)}%)`);
+
+fs.writeFileSync(`./${W_NAME}/build/cjs/bytes.js`, `// Copyright 2019-2021 @polkadot/${W_NAME} authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
 // Generated as part of the build, do not edit
-`;
-}
 
-function getWasmBuffer () {
-  const data = fs.readFileSync('./bytes/wasm_opt.wasm');
-  const compressed = Buffer.from(fflate.zlibSync(data, { level: 9 }));
-
-  console.log(`*** Compressed WASM: ${formatNumber(data.length)} -> ${formatNumber(compressed.length)} (${(100 * compressed.length / data.length).toFixed(2)}%)`);
-
-  return { compressed, sizeUncompressed: data.length };
-}
-
-// fs.writeFileSync(`./${A_NAME}/build/data.js`, `${hdr(A_NAME)}
-// export { asmJsInit } from './data.cjs';
-// `);
-
-// fs.writeFileSync(`./${W_NAME}/build/bytes.js`, `${hdr(W_NAME)}
-// export { bytes, sizeCompressed, sizeUncompressed } from './bytes.cjs';
-// `);
-
-const { compressed, sizeUncompressed } = getWasmBuffer();
-
-fs.writeFileSync(`./${W_NAME}/build/cjs/bytes.js`, `${hdr(W_NAME)}
 const sizeCompressed = ${compressed.length};
-const sizeUncompressed = ${sizeUncompressed};
+const sizeUncompressed = ${data.length};
 const bytes = '${compressed.toString('base64')}';
 
 module.exports = { bytes, sizeCompressed, sizeUncompressed };
diff --git a/scripts/rust-version.sh b/scripts/rust-version.sh
new file mode 100755
index 00000000..136f2e67
--- /dev/null
+++ b/scripts/rust-version.sh
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+# Copyright 2019-2021 @polkadot/wasm authors & contributors
+# This software may be modified and distributed under the terms
+# of the Apache-2.0 license. See the LICENSE file for details.
+
+RUST_VER=nightly-2020-10-25
+# RUST_VER=stable