Install Golang 1.9:

```
wget https://storage.googleapis.com/golang/go1.9.linux-armv6l.tar.gz
sudo tar -C /usr/local -xzf go1.9.linux-armv6l.tar.gz
export PATH=$PATH:/usr/local/go/bin # put into ~/.profile
```

If already installed old golang with apt-get:

```
sudo apt remove golang
sudo apt-get autoremove
source .profile
```

Test:

```
go version
```