diff --git a/pkg/dev_compiler/bin/devc.dart b/pkg/dev_compiler/bin/devc.dart
index a2d280b8141a..dab78980c242 100755
--- a/pkg/dev_compiler/bin/devc.dart
+++ b/pkg/dev_compiler/bin/devc.dart
@@ -33,6 +33,8 @@ final ArgParser argParser = new ArgParser()
   ..addFlag('force-compile',
       help: 'Compile code with static errors', defaultsTo: false)
   ..addFlag('help', abbr: 'h', help: 'Display this message')
+  ..addFlag('ignore-types',
+      help: 'Ignore types during codegen', defaultsTo: false)
   ..addOption('log', abbr: 'l', help: 'Logging level', defaultsTo: 'severe')
   ..addFlag('mock-sdk',
       abbr: 'm', help: 'Use a mock Dart SDK', defaultsTo: false)
@@ -109,6 +111,7 @@ void main(List<String> argv) {
       dumpSrcDir: args['dump-src-to'],
       forceCompile: args['force-compile'],
       formatOutput: args['dart-gen-fmt'],
+      ignoreTypes: args['ignore-types'],
       outputDart: args['dart-gen'],
       outputDir: args['out'],
       covariantGenerics: args['covariant-generics'],
diff --git a/pkg/dev_compiler/lib/src/checker/rules.dart b/pkg/dev_compiler/lib/src/checker/rules.dart
index f0b0578e977d..e1da9b8ba486 100644
--- a/pkg/dev_compiler/lib/src/checker/rules.dart
+++ b/pkg/dev_compiler/lib/src/checker/rules.dart
@@ -37,25 +37,10 @@ abstract class TypeRules {
 
   DartType elementType(Element e);
 
-  /// Returns `true` if the target expression is dynamic.
-  bool isDynamicTarget(Expression expr) => getStaticType(expr).isDynamic;
-
-  /// Returns `true` if the expression is a dynamic property access or prefixed
-  /// identifier.
-  bool isDynamicGet(Expression expr) {
-    var t = getStaticType(expr);
-    // TODO(jmesserly): we should not allow all property gets on `Function`
-    return t.isDynamic || t.isDartCoreFunction;
-  }
-
-  /// Returns `true` if the expression is a dynamic function call or method
-  /// invocation.
-  bool isDynamicCall(Expression call) {
-    var t = getStaticType(call);
-    // TODO(jmesserly): fix handling of types with `call` methods. These are not
-    // FunctionType, but they also aren't dynamic calls.
-    return t.isDynamic || t.isDartCoreFunction || t is! FunctionType;
-  }
+  bool isDynamic(DartType t);
+  bool isDynamicTarget(Expression expr);
+  bool isDynamicGet(Expression expr);
+  bool isDynamicCall(Expression call);
 }
 
 class DartRules extends TypeRules {
@@ -80,6 +65,12 @@ class DartRules extends TypeRules {
   DartType elementType(Element e) {
     return (e as dynamic).type;
   }
+
+  /// By default, all invocations are dynamic in Dart.
+  bool isDynamic(DartType t) => true;
+  bool isDynamicTarget(Expression expr) => true;
+  bool isDynamicGet(Expression expr) => true;
+  bool isDynamicCall(Expression call) => true;
 }
 
 class RestrictedRules extends TypeRules {
@@ -473,4 +464,29 @@ class RestrictedRules extends TypeRules {
   DartType elementType(Element e) {
     return (e as dynamic).type;
   }
+
+  bool isDynamic(DartType t) => options.ignoreTypes || t.isDynamic;
+
+  /// Returns `true` if the target expression is dynamic.
+  bool isDynamicTarget(Expression expr) =>
+      options.ignoreTypes || getStaticType(expr).isDynamic;
+
+  /// Returns `true` if the expression is a dynamic property access or prefixed
+  /// identifier.
+  bool isDynamicGet(Expression expr) {
+    if (options.ignoreTypes) return true;
+    var t = getStaticType(expr);
+    // TODO(jmesserly): we should not allow all property gets on `Function`
+    return t.isDynamic || t.isDartCoreFunction;
+  }
+
+  /// Returns `true` if the expression is a dynamic function call or method
+  /// invocation.
+  bool isDynamicCall(Expression call) {
+    if (options.ignoreTypes) return true;
+    var t = getStaticType(call);
+    // TODO(jmesserly): fix handling of types with `call` methods. These are not
+    // FunctionType, but they also aren't dynamic calls.
+    return t.isDynamic || t.isDartCoreFunction || t is! FunctionType;
+  }
 }
diff --git a/pkg/dev_compiler/lib/src/codegen/js_codegen.dart b/pkg/dev_compiler/lib/src/codegen/js_codegen.dart
index 30deb7fe7c63..1ccc69ca2cd1 100644
--- a/pkg/dev_compiler/lib/src/codegen/js_codegen.dart
+++ b/pkg/dev_compiler/lib/src/codegen/js_codegen.dart
@@ -1052,10 +1052,11 @@ $name.prototype[Symbol.iterator] = function() {
   bool _isJSBuiltinType(DartType t) =>
       rules.isNumType(t) || rules.isStringType(t) || rules.isBoolType(t);
 
-  bool typeIsPrimitiveInJS(DartType t) => rules.isIntType(t) ||
-      rules.isDoubleType(t) ||
-      rules.isBoolType(t) ||
-      rules.isNumType(t);
+  bool typeIsPrimitiveInJS(DartType t) => !rules.isDynamic(t) &&
+      (rules.isIntType(t) ||
+          rules.isDoubleType(t) ||
+          rules.isBoolType(t) ||
+          rules.isNumType(t));
 
   bool typeIsNonNullablePrimitiveInJS(DartType t) =>
       typeIsPrimitiveInJS(t) && rules.isNonNullableType(t);
diff --git a/pkg/dev_compiler/lib/src/options.dart b/pkg/dev_compiler/lib/src/options.dart
index a3a580cbd25a..c9f07933649e 100644
--- a/pkg/dev_compiler/lib/src/options.dart
+++ b/pkg/dev_compiler/lib/src/options.dart
@@ -64,7 +64,11 @@ class RulesOptions extends TypeOptions {
   /// Whether to inject casts between Dart assignable types.
   final bool relaxedCasts;
 
-  RulesOptions({this.covariantGenerics: true, this.relaxedCasts: true});
+  /// Whether to use static types for code generation.
+  final bool ignoreTypes;
+
+  RulesOptions({this.covariantGenerics: true, this.relaxedCasts: true,
+      this.ignoreTypes: false});
 }
 
 /// General options used by the dev compiler.
@@ -140,13 +144,18 @@ class CompilerOptions implements RulesOptions, ResolverOptions {
   @override
   final List<String> nonnullableTypes;
 
+  /// Whether to use static types for code generation.
+  @override
+  final bool ignoreTypes;
+
   CompilerOptions({this.checkSdk: false, this.dumpInfo: false,
       this.dumpInfoFile, this.dumpSrcDir, this.forceCompile: false,
-      this.formatOutput: false, this.outputDir, this.outputDart: false,
-      this.useColors: true, this.covariantGenerics: true,
-      this.relaxedCasts: true, this.useMultiPackage: false,
-      this.packageRoot: 'packages/', this.packagePaths: const [],
-      this.inferFromOverrides: true, this.inferStaticsFromIdentifiers: false,
+      this.formatOutput: false, this.ignoreTypes: false, this.outputDir,
+      this.outputDart: false, this.useColors: true,
+      this.covariantGenerics: true, this.relaxedCasts: true,
+      this.useMultiPackage: false, this.packageRoot: 'packages/',
+      this.packagePaths: const [], this.inferFromOverrides: true,
+      this.inferStaticsFromIdentifiers: false,
       this.inferInNonStableOrder: false,
       this.onlyInferConstsAndFinalFields: false,
       this.nonnullableTypes: TypeOptions.NONNULLABLE_TYPES});