gradle-docker-plugin: Building images on OSX does not seem to work

The task is defined as such:

task buildImage(type: DockerBuildImage) {
    inputDir = createDockerFile.destFile.parentFile
    tag = "myTag"
}

If I run this, I get a Connection Refused message:

Connect to localhost:2375 [localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1] failed: Connection refused

This makes sense, that’s not where docker is running locally. If I grab the URL from docker-machine and specify it as such:

docker {
    url = "http://192.168.99.100:2376"
}

I can get past the Connection Refused message, but it still fails with a broken pipe:

[pool-16-thread-1] INFO org.apache.http.impl.execchain.RetryExec - I/O exception (java.net.SocketException) caught when processing request: Broken pipe
[pool-16-thread-1] ERROR com.github.dockerjava.core.async.ResultCallbackTemplate - Error during callback
org.apache.http.client.ClientProtocolException
    at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:188)
    at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:72)
    at com.github.dockerjava.jaxrs.connector.ApacheConnector.apply(ApacheConnector.java:441)
    at org.glassfish.jersey.client.ClientRuntime.invoke(ClientRuntime.java:246)
    at org.glassfish.jersey.client.JerseyInvocation$2.call(JerseyInvocation.java:683)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:228)
    at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:424)
    at org.glassfish.jersey.client.JerseyInvocation.invoke(JerseyInvocation.java:679)
    at org.glassfish.jersey.client.JerseyInvocation$Builder.method(JerseyInvocation.java:435)
    at org.glassfish.jersey.client.JerseyInvocation$Builder.post(JerseyInvocation.java:338)
    at com.github.dockerjava.jaxrs.async.POSTCallbackNotifier.response(POSTCallbackNotifier.java:29)
    at com.github.dockerjava.jaxrs.async.AbstractCallbackNotifier.call(AbstractCallbackNotifier.java:45)
    at com.github.dockerjava.jaxrs.async.AbstractCallbackNotifier.call(AbstractCallbackNotifier.java:22)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.http.client.NonRepeatableRequestException: Cannot retry request with a non-repeatable request entity
    at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:102)
    at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:108)
    at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:186)
    ... 18 more
Caused by: java.net.SocketException: Broken pipe
    at java.net.SocketOutputStream.socketWrite0(Native Method)
    at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:109)
    at java.net.SocketOutputStream.write(SocketOutputStream.java:153)
    at org.apache.http.impl.io.SessionOutputBufferImpl.streamWrite(SessionOutputBufferImpl.java:123)
    at org.apache.http.impl.io.SessionOutputBufferImpl.flushBuffer(SessionOutputBufferImpl.java:135)
    at org.apache.http.impl.io.SessionOutputBufferImpl.write(SessionOutputBufferImpl.java:164)
    at org.apache.http.impl.io.SessionOutputBufferImpl.write(SessionOutputBufferImpl.java:175)
    at org.apache.http.impl.io.SessionOutputBufferImpl.writeLine(SessionOutputBufferImpl.java:213)
    at org.apache.http.impl.io.ChunkedOutputStream.flushCacheWithAppend(ChunkedOutputStream.java:125)
    at org.apache.http.impl.io.ChunkedOutputStream.write(ChunkedOutputStream.java:181)
    at org.glassfish.jersey.message.internal.CommittingOutputStream.write(CommittingOutputStream.java:229)
    at org.glassfish.jersey.message.internal.WriterInterceptorExecutor$UnCloseableOutputStream.write(WriterInterceptorExecutor.java:299)
    at org.glassfish.jersey.message.internal.ReaderWriter.writeTo(ReaderWriter.java:114)
    at org.glassfish.jersey.message.internal.AbstractMessageReaderWriterProvider.writeTo(AbstractMessageReaderWriterProvider.java:77)
    at org.glassfish.jersey.message.internal.InputStreamProvider.writeTo(InputStreamProvider.java:105)
    at org.glassfish.jersey.message.internal.InputStreamProvider.writeTo(InputStreamProvider.java:60)
    at org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor.invokeWriteTo(WriterInterceptorExecutor.java:265)
    at org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor.aroundWriteTo(WriterInterceptorExecutor.java:250)
    at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162)
    at com.github.dockerjava.jaxrs.filter.LoggingFilter.aroundWriteTo(LoggingFilter.java:301)
    at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162)
    at org.glassfish.jersey.message.internal.MessageBodyFactory.writeTo(MessageBodyFactory.java:1154)
    at org.glassfish.jersey.client.ClientRequest.writeEntity(ClientRequest.java:503)
    at com.github.dockerjava.jaxrs.connector.ApacheConnector$2.writeTo(ApacheConnector.java:576)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.apache.http.impl.execchain.RequestEntityExecHandler.invoke(RequestEntityExecHandler.java:77)
    at com.sun.proxy.$Proxy382.writeTo(Unknown Source)
    at org.apache.http.impl.DefaultBHttpClientConnection.sendRequestEntity(DefaultBHttpClientConnection.java:155)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.apache.http.impl.conn.CPoolProxy.invoke(CPoolProxy.java:138)
    at com.sun.proxy.$Proxy383.sendRequestEntity(Unknown Source)
    at org.apache.http.protocol.HttpRequestExecutor.doSendRequest(HttpRequestExecutor.java:236)
    at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:121)
    at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:253)
    at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:194)
    at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:85)
    ... 20 more

Is the plugin not supported on OSX or am I not configuring it correctly?