diff --git a/Android.bp b/Android.bp
index a2ce8a3..89bd6ea 100644
--- a/Android.bp
+++ b/Android.bp
@@ -222,7 +222,7 @@
     ],
     srcs: [
         "java/config/config.go",
-        "java/config/errorprone.go",
+        "java/config/error_prone.go",
         "java/config/makevars.go",
     ],
 }
diff --git a/java/builder.go b/java/builder.go
index 6912c87..e359529 100644
--- a/java/builder.go
+++ b/java/builder.go
@@ -21,9 +21,10 @@
 import (
 	"strings"
 
-	"android/soong/android"
-
 	"github.com/google/blueprint"
+
+	"android/soong/android"
+	"android/soong/java/config"
 )
 
 var (
@@ -166,6 +167,11 @@
 func RunErrorProne(ctx android.ModuleContext, srcFiles android.Paths, srcFileLists android.Paths,
 	flags javaBuilderFlags, deps android.Paths) android.Path {
 
+	if config.ErrorProneJar == "" {
+		ctx.ModuleErrorf("cannot build with Error Prone, missing external/error_prone?")
+		return nil
+	}
+
 	classDir := android.PathForModuleOut(ctx, "classes-errorprone")
 	annoDir := android.PathForModuleOut(ctx, "anno-errorprone")
 	classFileList := android.PathForModuleOut(ctx, "classes-errorprone.list")
diff --git a/java/config/config.go b/java/config/config.go
index 4a5a2dd..047c4cb 100644
--- a/java/config/config.go
+++ b/java/config/config.go
@@ -26,15 +26,14 @@
 var (
 	pctx = android.NewPackageContext("android/soong/java/config")
 
-	JavacHeapSize = "2048M"
-
 	DefaultLibraries = []string{"core-oj", "core-libart", "ext", "framework", "okhttp"}
 )
 
 func init() {
 	pctx.Import("github.com/google/blueprint/bootstrap")
 
-	pctx.StaticVariable("JavacHeapFlags", "-J-Xmx"+JavacHeapSize)
+	pctx.StaticVariable("JavacHeapSize", "2048M")
+	pctx.StaticVariable("JavacHeapFlags", "-J-Xmx${JavacHeapSize}")
 
 	pctx.StaticVariable("CommonJdkFlags", strings.Join([]string{
 		`-Xmaxerrs 9999999`,
diff --git a/java/config/error_prone.go b/java/config/error_prone.go
new file mode 100644
index 0000000..31cbf2c
--- /dev/null
+++ b/java/config/error_prone.go
@@ -0,0 +1,45 @@
+// Copyright 2017 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+var (
+	// These will be filled out by external/error_prone/soong/error_prone.go if it is available
+	ErrorProneJavacJar    string
+	ErrorProneJar         string
+	ErrorProneClasspath   string
+	ErrorProneChecksError string
+	ErrorProneFlags       string
+)
+
+// Wrapper that grabs value of val late so it can be initialized by a later module's init function
+func errorProneVar(name string, val *string) {
+	pctx.VariableFunc(name, func(config interface{}) (string, error) {
+		return *val, nil
+	})
+}
+
+func init() {
+	errorProneVar("ErrorProneJar", &ErrorProneJar)
+	errorProneVar("ErrorProneJavacJar", &ErrorProneJavacJar)
+	errorProneVar("ErrorProneClasspath", &ErrorProneClasspath)
+	errorProneVar("ErrorProneChecksError", &ErrorProneChecksError)
+	errorProneVar("ErrorProneFlags", &ErrorProneFlags)
+
+	pctx.StaticVariable("ErrorProneCmd",
+		"${JavaCmd} -Xmx${JavacHeapSize} -Xbootclasspath/p:${ErrorProneJavacJar} "+
+			"-cp ${ErrorProneJar}:${ErrorProneClasspath} "+
+			"${ErrorProneFlags} ${CommonJdkFlags} ${ErrorProneChecksError}")
+
+}
diff --git a/java/config/errorprone.go b/java/config/errorprone.go
deleted file mode 100644
index ddb9902..0000000
--- a/java/config/errorprone.go
+++ /dev/null
@@ -1,100 +0,0 @@
-// Copyright 2017 Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package config
-
-import (
-	"strings"
-)
-
-func init() {
-	pctx.SourcePathVariable("ErrorProneJavacJar", "external/error_prone/javac/javac-9-dev-r3297-4.jar")
-	pctx.SourcePathVariable("ErrorProneJar", "external/error_prone/error_prone/error_prone_core-2.0.19-with-dependencies.jar")
-	pctx.SourcePathsVariable("ErrorProneClasspath", ":",
-		"external/error_prone/error_prone/error_prone_annotations-2.0.19.jar",
-		"external/error_prone/checkerframework/dataflow-1.8.10.jar",
-		"external/error_prone/checkerframework/javacutil-1.8.10.jar",
-		"external/error_prone/jFormatString/jFormatString-3.0.0.jar")
-
-	// The checks that are fatal to the build.
-	pctx.StaticVariable("ErrorProneChecksError", strings.Join([]string{
-		"-Xep:AsyncCallableReturnsNull:ERROR",
-		"-Xep:AsyncFunctionReturnsNull:ERROR",
-		"-Xep:BundleDeserializationCast:ERROR",
-		"-Xep:CompatibleWithAnnotationMisuse:ERROR",
-		"-Xep:CompileTimeConstant:ERROR",
-		"-Xep:DaggerProvidesNull:ERROR",
-		"-Xep:DoNotCall:ERROR",
-		"-Xep:ForOverride:ERROR",
-		"-Xep:FunctionalInterfaceMethodChanged:ERROR",
-		"-Xep:FuturesGetCheckedIllegalExceptionType:ERROR",
-		"-Xep:GuiceAssistedInjectScoping:ERROR",
-		"-Xep:GuiceAssistedParameters:ERROR",
-		"-Xep:GuiceInjectOnFinalField:ERROR",
-		"-Xep:Immutable:ERROR",
-		"-Xep:ImmutableModification:ERROR",
-		"-Xep:IncompatibleArgumentType:ERROR",
-		"-Xep:IndexOfChar:ERROR",
-		"-Xep:InjectMoreThanOneScopeAnnotationOnClass:ERROR",
-		"-Xep:JavaxInjectOnAbstractMethod:ERROR",
-		"-Xep:JUnit4SetUpNotRun:ERROR",
-		"-Xep:JUnit4TearDownNotRun:ERROR",
-		"-Xep:JUnit4TestNotRun:ERROR",
-		"-Xep:JUnitAssertSameCheck:ERROR",
-		"-Xep:LiteByteStringUtf8:ERROR",
-		"-Xep:LoopConditionChecker:ERROR",
-		"-Xep:MockitoCast:ERROR",
-		"-Xep:MockitoUsage:ERROR",
-		"-Xep:MoreThanOneInjectableConstructor:ERROR",
-		"-Xep:MustBeClosedChecker:ERROR",
-		"-Xep:NonCanonicalStaticImport:ERROR",
-		"-Xep:NonFinalCompileTimeConstant:ERROR",
-		"-Xep:OptionalEquality:ERROR",
-		"-Xep:OverlappingQualifierAndScopeAnnotation:ERROR",
-		"-Xep:PackageInfo:ERROR",
-		"-Xep:PreconditionsCheckNotNull:ERROR",
-		"-Xep:PreconditionsCheckNotNullPrimitive:ERROR",
-		"-Xep:ProtoFieldNullComparison:ERROR",
-		"-Xep:ProvidesMethodOutsideOfModule:ERROR",
-		"-Xep:RestrictedApiChecker:ERROR",
-		"-Xep:SelfAssignment:ERROR",
-		"-Xep:StreamToString:ERROR",
-		"-Xep:SuppressWarningsDeprecated:ERROR",
-		"-Xep:ThrowIfUncheckedKnownChecked:ERROR",
-		"-Xep:ThrowNull:ERROR",
-		"-Xep:TypeParameterQualifier:ERROR",
-		"-Xep:UnnecessaryTypeArgument:ERROR",
-		"-Xep:UnusedAnonymousClass:ERROR",
-	}, " "))
-
-	pctx.StaticVariable("ErrorProneHeapFlags", "-Xmx"+JavacHeapSize)
-
-	pctx.StaticVariable("ErrorProneFlags", strings.Join([]string{
-		"com.google.errorprone.ErrorProneCompiler",
-		"-Xdiags:verbose",
-		"-XDcompilePolicy=simple",
-		"-XDallowBetterNullChecks=false",
-		"-XDusePolyAttribution=true",
-		"-XDuseStrictMethodClashCheck=true",
-		"-XDuseStructuralMostSpecificResolution=true",
-		"-XDuseGraphInference=true",
-		"-XDandroidCompatible=true",
-		"-XepAllErrorsAsWarnings",
-	}, " "))
-
-	pctx.StaticVariable("ErrorProneCmd",
-		"${JavaCmd} ${ErrorProneHeapFlags} -Xbootclasspath/p:${ErrorProneJavacJar} "+
-			"-cp ${ErrorProneJar}:${ErrorProneClasspath} "+
-			"${ErrorProneFlags} ${CommonJdkFlags} ${ErrorProneChecksError}")
-}