grule engine build is failing

[nagarajtrivedi]

Hi all, I have downloaded the grule engine source code from the github
While trying to build the code

make build

it failed displaying the error message

~/go/grule-rule-engine$ make build
sed -i.origin.bak "s/1[ ]*<</int64(1) <</g" antlr/parser/grulev3/grulev3_parser.go
export GO111MODULE on;
go build ./...
go: cannot find GOROOT directory: /usr/local/opt/go/libexec
Makefile:9: recipe for target 'build' failed
make: *** [build] Error 2

I have properly set the export path in the ~/.bashrc file
export PATH=$PATH:$GOPATH/bin

and in the ~/.bash_profile
export GOPATH="${HOME}/go"
export GOROOT="/usr/local/opt/go/libexec"

and then did
source ~/.bashrc
source ~/.bash_profile

Even then it gave the error message
go: cannot find GOROOT directory: /usr/local/opt/go/libexec
Makefile:9: recipe for target 'build' failed
make: *** [build] Error 2

Let me know what could be the problem

Thanks
Nagaraj