gulp error after upgrading to nodejs v10.x and npm v6.4.0

[broweratcognitecdotcom]

@cognitec/[email protected] build /build/brower/gitrepos/FaceVACS-VideoScan-WA-Development/src/packages/@cognitec/http-request-indicator
gulp build

gulp[17785]: ../src/node_contextify.cc:629:static void node::contextify::ContextifyScript::New(const v8::FunctionCallbackInfov8::Value&): Assertion args[1]->IsString()' failed. 1: node::Abort() [gulp] 2: 0x8938b5 [gulp] 3: node::contextify::ContextifyScript::New(v8::FunctionCallbackInfo<v8::Value> const&) [gulp] 4: 0xaff5e8 [gulp] 5: v8::internal::Builtin_HandleApiCall(int, v8::internal::Object**, v8::internal::Isolate*) [gulp] 6: 0x2a7108d841bd Aborted npm ERR! code ELIFECYCLE npm ERR! errno 134 npm ERR! @cognitec/[email protected] build: gulp build`
npm ERR! Exit status 134
npm ERR!
npm ERR! Failed at the @cognitec/[email protected] build script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! /home/brower/.npm/_logs/2018-08-24T10_20_04_456Z-debug.log
(node:17654) UnhandledPromiseRejectionWarning: Error: Command failed: npm run build
at checkExecSyncError (child_process.js:603:11)
at execSync (child_process.js:640:13)
at buildCallback (/build/brower/gitrepos/FaceVACS-VideoScan-WA-Development/src/build/build-package.js:103:5)
at buildPackage (/build/brower/gitrepos/FaceVACS-VideoScan-WA-Development/src/build/build-package.js:151:13)
at build.buildPackages.forEach.package (/build/brower/gitrepos/FaceVACS-VideoScan-WA-Development/src/build/build.js:259:48)
at Array.forEach ()
at buildPackages (/build/brower/gitrepos/FaceVACS-VideoScan-WA-Development/src/build/build.js:259:29)
at menu5Callback (/build/brower/gitrepos/FaceVACS-VideoScan-WA-Development/src/build/build.js:249:5)
at menu.then.item (/build/brower/gitrepos/FaceVACS-VideoScan-WA-Development/src/build/build.js:214:13)
at process._tickCallback (internal/process/next_tick.js:68:7)
(node:17654) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:17654) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

We are unable to upgrade to Angular 6.

[broweratcognitecdotcom]

node-sass is extremely problematic in our linux environment. the hours or days we have spent sorting out node-sass problems is incredible. is there no other alternative to this?