Fixed bug in libnss-resolver DNS resolution

Dockerfile

@@ -1,19 +1,25 @@
-FROM golang:1.9-alpine
+FROM golang:1.9
 
-RUN apk add --no-cache \
-  ca-certificates \
-  git \
-  gcc \
-  libffi-dev \
-  make \
-  musl-dev \
-  rpm \
-  ruby \
-  ruby-dev \
-  tar \
-  && go get -u github.com/golang/dep/... \
+# Install Ruby
+WORKDIR /tmp
+RUN apt-get -y update \
+    && apt-get -y install build-essential zlib1g-dev libssl-dev libreadline6-dev libyaml-dev
+RUN wget https://cache.ruby-lang.org/pub/ruby/2.4/ruby-2.4.2.tar.gz \
+    && tar xzf ruby-2.4.2.tar.gz \
+    && cd ruby-2.4.2 \
+    && ./configure --prefix=/usr/local \
+    && make \
+    && make install
+
+# Install fpm for package building
+RUN apt-get install -y rpm \
+    && apt-get clean \
+    && rm -rf /var/lib/apt/lists \
+    && gem install --no-rdoc --no-ri fpm
+
+# Back to the Go thingies
+WORKDIR /go
+RUN go get -u github.com/golang/dep/... \
   && go get -u github.com/alecthomas/gometalinter \
   && go get -u github.com/goreleaser/goreleaser
-
 RUN gometalinter --install --update
-RUN gem install --no-rdoc --no-ri fpm

commands/dns.go

@@ -209,7 +209,7 @@ func (cmd *DNS) configureLinuxResolver() error {
 	// Is libnss-resolver in use
 	if _, err := os.Stat("/etc/resolver"); err == nil {
 		// Install for libnss-resolver connection to dnsdock
-		exec.Command("bash", "-c", fmt.Sprintf("echo 'nameserver %s' | sudo tee /etc/resolver/vm", bridgeIP)).Run()
+		exec.Command("bash", "-c", fmt.Sprintf("echo 'nameserver %s:53' | sudo tee /etc/resolver/vm", bridgeIP)).Run()
 	}
 
 	return nil

docker-compose.yml

@@ -19,10 +19,10 @@ services:
   # Build rig, dropping off a working binary in build/darwin/rig.
   compile:
     extends: base
-    command: go build -o build/darwin/rig cmd/main.go
+    command: go build -o build/${GOOS:-darwin}/rig cmd/main.go
     environment:
-      - GOOS=darwin
-      - GOARCH=amd64
+      GOOS: ${GOOS:-darwin}
+      GOARCH: ${GOARCH:-amd64}
 
   # Install project dependencies.
   install: