diff --git a/crates/backend/src/ast.rs b/crates/backend/src/ast.rs
index 2c3c9661..cfdc2367 100644
--- a/crates/backend/src/ast.rs
+++ b/crates/backend/src/ast.rs
@@ -42,6 +42,7 @@ pub enum ImportKind {
     Static(ImportStatic),
     Type(ImportType),
     Enum(ImportEnum),
+    Const(Const),
 }
 
 #[cfg_attr(feature = "extra-traits", derive(Debug, PartialEq, Eq))]
@@ -174,6 +175,24 @@ pub struct TypeAlias {
     pub src: syn::Type,
 }
 
+#[cfg_attr(feature = "extra-traits", derive(Debug, PartialEq, Eq))]
+pub struct Const {
+    pub vis: syn::Visibility,
+    pub name: Ident,
+    pub interface_name: Ident,
+    pub ty: syn::Type,
+    pub value: ConstValue,
+}
+
+#[cfg_attr(feature = "extra-traits", derive(Debug, PartialEq, Eq))]
+/// same as webidl::ast::ConstValue
+pub enum ConstValue {
+    BooleanLiteral(bool),
+    FloatLiteral(f64),
+    IntegerLiteral(i64),
+    Null,
+}
+
 impl Program {
     pub(crate) fn shared(&self) -> shared::Program {
         shared::Program {
@@ -293,6 +312,7 @@ impl ImportKind {
             ImportKind::Static(_) => false,
             ImportKind::Type(_) => false,
             ImportKind::Enum(_) => false,
+            ImportKind::Const(_) => false,
         }
     }
 
@@ -302,6 +322,7 @@ impl ImportKind {
             ImportKind::Static(ref f) => shared::ImportKind::Static(f.shared()),
             ImportKind::Type(ref f) => shared::ImportKind::Type(f.shared()),
             ImportKind::Enum(ref f) => shared::ImportKind::Enum(f.shared()),
+            ImportKind::Const(ref f) => shared::ImportKind::Const(f.shared()),
         }
     }
 }
@@ -404,3 +425,9 @@ impl StructField {
         }
     }
 }
+
+impl Const {
+    fn shared(&self) -> shared::Const {
+        shared::Const {}
+    }
+}
diff --git a/crates/backend/src/codegen.rs b/crates/backend/src/codegen.rs
index 1e3e69af..a83d1923 100644
--- a/crates/backend/src/codegen.rs
+++ b/crates/backend/src/codegen.rs
@@ -501,6 +501,7 @@ impl ToTokens for ast::ImportKind {
             ast::ImportKind::Static(ref s) => s.to_tokens(tokens),
             ast::ImportKind::Type(ref t) => t.to_tokens(tokens),
             ast::ImportKind::Enum(ref e) => e.to_tokens(tokens),
+            ast::ImportKind::Const(ref c) => c.to_tokens(tokens),
         }
     }
 }
@@ -842,6 +843,7 @@ impl<'a> ToTokens for DescribeImport<'a> {
             ast::ImportKind::Static(_) => return,
             ast::ImportKind::Type(_) => return,
             ast::ImportKind::Enum(_) => return,
+            ast::ImportKind::Const(_) => return,
         };
         let describe_name = format!("__wbindgen_describe_{}", f.shim);
         let describe_name = Ident::new(&describe_name, Span::call_site());
@@ -958,3 +960,41 @@ impl ToTokens for ast::TypeAlias {
         }).to_tokens(into);
     }
 }
+
+impl ToTokens for ast::Const {
+    fn to_tokens(&self, tokens: &mut TokenStream) {
+        use ast::ConstValue::*;
+
+        let vis = &self.vis;
+        let name = &self.name;
+        let interface_name = &self.interface_name;
+        let ty = &self.ty;
+
+        let value: TokenStream = match self.value {
+            BooleanLiteral(false) => quote!(false),
+            BooleanLiteral(true) => quote!(true),
+            // the actual type is unknown because of typedefs
+            // so we cannot use std::fxx::INFINITY
+            // but we can use type inference
+            FloatLiteral(f) if f.is_infinite() && f.is_sign_positive() => quote!(1.0 / 0.0),
+            FloatLiteral(f) if f.is_infinite() && f.is_sign_negative() => quote!(-1.0 / 0.0),
+            FloatLiteral(f) if f.is_nan() => quote!(0.0 / 0.0),
+            // again no suffix
+            // panics on +-inf, nan
+            FloatLiteral(f) => {
+                let f = Literal::f64_unsuffixed(f);
+                quote!(#f)
+            },
+            IntegerLiteral(i) => {
+                let i = Literal::i64_unsuffixed(i);
+                quote!(#i)
+            },
+            Null => unimplemented!(),
+        };
+        (quote! {
+            impl #interface_name {
+                #vis const #name: #ty = #value;
+            }
+        }).to_tokens(tokens);
+    }
+}
diff --git a/crates/backend/src/defined.rs b/crates/backend/src/defined.rs
index d775cb02..84eabe50 100644
--- a/crates/backend/src/defined.rs
+++ b/crates/backend/src/defined.rs
@@ -106,6 +106,7 @@ impl ImportedTypes for ast::ImportKind {
             ast::ImportKind::Function(fun) => fun.imported_types(f),
             ast::ImportKind::Type(ty) => ty.imported_types(f),
             ast::ImportKind::Enum(enm) => enm.imported_types(f),
+            ast::ImportKind::Const(c) => c.imported_types(f),
         }
     }
 }
@@ -229,6 +230,15 @@ impl ImportedTypes for ast::TypeAlias {
     }
 }
 
+impl ImportedTypes for ast::Const {
+    fn imported_types<F>(&self, f: &mut F)
+    where
+        F: FnMut(&Ident, ImportedTypeKind),
+    {
+        self.ty.imported_types(f);
+    }
+}
+
 /// Remove any methods, statics, &c, that reference types that are *not*
 /// defined.
 pub trait RemoveUndefinedImports {
diff --git a/crates/cli-support/Cargo.toml b/crates/cli-support/Cargo.toml
index 7cf552f2..09ef9558 100644
--- a/crates/cli-support/Cargo.toml
+++ b/crates/cli-support/Cargo.toml
@@ -19,5 +19,5 @@ serde_derive = "1.0"
 serde_json = "1.0"
 tempfile = "3.0"
 wasm-bindgen-shared = { path = "../shared", version = '=0.2.11' }
-wasm-gc-api = "0.1"
+wasm-gc-api = "0.1.8"
 wasmi = "0.3"
diff --git a/crates/cli-support/src/js/mod.rs b/crates/cli-support/src/js/mod.rs
index ef47aa55..9a9a7271 100644
--- a/crates/cli-support/src/js/mod.rs
+++ b/crates/cli-support/src/js/mod.rs
@@ -1580,6 +1580,7 @@ impl<'a> Context<'a> {
         let wasm_bytes = parity_wasm::serialize(module)?;
         let bytes = wasm_gc::Config::new()
             .demangle(self.config.demangle)
+            .keep_debug(self.config.keep_debug || self.config.debug)
             .gc(&wasm_bytes)?;
         *self.module = deserialize_buffer(&bytes)?;
         Ok(())
@@ -1757,6 +1758,7 @@ impl<'a, 'b> SubContext<'a, 'b> {
             }
             shared::ImportKind::Type(_) => {}
             shared::ImportKind::Enum(_) => {}
+            shared::ImportKind::Const(_) => {}
         }
         Ok(())
     }
diff --git a/crates/cli-support/src/lib.rs b/crates/cli-support/src/lib.rs
index 410700f3..a9a88769 100644
--- a/crates/cli-support/src/lib.rs
+++ b/crates/cli-support/src/lib.rs
@@ -31,6 +31,7 @@ pub struct Bindgen {
     debug: bool,
     typescript: bool,
     demangle: bool,
+    keep_debug: bool,
 }
 
 impl Bindgen {
@@ -45,6 +46,7 @@ impl Bindgen {
             debug: false,
             typescript: false,
             demangle: true,
+            keep_debug: false,
         }
     }
 
@@ -93,6 +95,11 @@ impl Bindgen {
         self
     }
 
+    pub fn keep_debug(&mut self, keep_debug: bool) -> &mut Bindgen {
+        self.keep_debug = keep_debug;
+        self
+    }
+
     pub fn generate<P: AsRef<Path>>(&mut self, path: P) -> Result<(), Error> {
         self._generate(path.as_ref())
     }
diff --git a/crates/cli/src/bin/wasm-bindgen.rs b/crates/cli/src/bin/wasm-bindgen.rs
index 606a3fee..996bf5aa 100644
--- a/crates/cli/src/bin/wasm-bindgen.rs
+++ b/crates/cli/src/bin/wasm-bindgen.rs
@@ -32,6 +32,7 @@ Options:
     --no-typescript          Don't emit a *.d.ts file
     --debug                  Include otherwise-extraneous debug checks in output
     --no-demangle            Don't demangle Rust symbol names
+    --keep-debug             Keep debug sections in wasm files
     -V --version             Print the version number of wasm-bindgen
 ";
 
@@ -47,6 +48,7 @@ struct Args {
     flag_version: bool,
     flag_no_demangle: bool,
     flag_no_modules_global: Option<String>,
+    flag_keep_debug: bool,
     arg_input: Option<PathBuf>,
 }
 
@@ -85,6 +87,7 @@ fn rmain(args: &Args) -> Result<(), Error> {
         .no_modules(args.flag_no_modules)
         .debug(args.flag_debug)
         .demangle(!args.flag_no_demangle)
+        .keep_debug(args.flag_keep_debug)
         .typescript(typescript);
     if let Some(ref name) = args.flag_no_modules_global {
         b.no_modules_global(name);
diff --git a/crates/shared/src/lib.rs b/crates/shared/src/lib.rs
index 8df1e534..8985733d 100644
--- a/crates/shared/src/lib.rs
+++ b/crates/shared/src/lib.rs
@@ -34,6 +34,7 @@ pub enum ImportKind {
     Static(ImportStatic),
     Type(ImportType),
     Enum(ImportEnum),
+    Const(Const)
 }
 
 #[derive(Deserialize, Serialize)]
@@ -124,6 +125,9 @@ pub struct StructField {
     pub comments: Vec<String>,
 }
 
+#[derive(Deserialize, Serialize)]
+pub struct Const {}
+
 pub fn new_function(struct_name: &str) -> String {
     let mut name = format!("__wbg_");
     name.extend(struct_name.chars().flat_map(|s| s.to_lowercase()));
diff --git a/crates/web-sys/tests/all/headers.rs b/crates/web-sys/tests/all/headers.rs
new file mode 100644
index 00000000..8431f4f4
--- /dev/null
+++ b/crates/web-sys/tests/all/headers.rs
@@ -0,0 +1,33 @@
+use super::websys_project;
+
+#[test]
+fn headers() {
+    websys_project()
+        .file(
+            "src/lib.rs",
+            r#"
+                #![feature(proc_macro, wasm_custom_section)]
+                extern crate wasm_bindgen;
+                use wasm_bindgen::prelude::*;
+                extern crate web_sys;
+
+                #[wasm_bindgen]
+                pub fn test_headers(_headers: &web_sys::Headers) {
+                    // empty for now...
+                }
+            "#,
+        )
+        .file(
+            "test.js",
+            r#"
+                import * as assert from "assert";
+                import * as wasm from "./out";
+
+                export function test() {
+                    let headers = new Headers({'Content-Type': 'text/plain'});
+                    wasm.test_headers(headers);
+                }
+            "#,
+        )
+        .test();
+}
diff --git a/crates/web-sys/tests/all/main.rs b/crates/web-sys/tests/all/main.rs
index e0181c24..181a596e 100644
--- a/crates/web-sys/tests/all/main.rs
+++ b/crates/web-sys/tests/all/main.rs
@@ -2,6 +2,7 @@ extern crate wasm_bindgen_test_project_builder as project_builder;
 use project_builder::{project, Project};
 
 mod event;
+mod headers;
 mod response;
 
 fn websys_project() -> Project {
diff --git a/crates/web-sys/webidls/available/Headers.webidl b/crates/web-sys/webidls/enabled/Headers.webidl
similarity index 100%
rename from crates/web-sys/webidls/available/Headers.webidl
rename to crates/web-sys/webidls/enabled/Headers.webidl
diff --git a/crates/webidl/src/lib.rs b/crates/webidl/src/lib.rs
index 02fe8224..37c18758 100644
--- a/crates/webidl/src/lib.rs
+++ b/crates/webidl/src/lib.rs
@@ -30,11 +30,11 @@ use std::path::Path;
 use backend::defined::{ImportedTypeDefinitions, RemoveUndefinedImports};
 use backend::util::{ident_ty, rust_ident, wrap_import_function};
 use failure::ResultExt;
-use heck::CamelCase;
+use heck::{CamelCase, ShoutySnakeCase};
 use quote::ToTokens;
 
 use first_pass::{FirstPass, FirstPassRecord};
-use util::{public, TypePosition};
+use util::{public, webidl_const_ty_to_syn_ty, webidl_const_v_to_backend_const_v, TypePosition};
 
 /// Either `Ok(t)` or `Err(failure::Error)`.
 pub type Result<T> = ::std::result::Result<T, failure::Error>;
@@ -250,7 +250,7 @@ impl WebidlParse<()> for webidl::ast::NonPartialInterface {
             js_namespace: None,
             kind: backend::ast::ImportKind::Type(backend::ast::ImportType {
                 vis: public(),
-                name: rust_ident(&self.name),
+                name: rust_ident(self.name.to_camel_case().as_str()),
                 attrs: Vec::new(),
             }),
         });
@@ -343,7 +343,8 @@ impl<'a> WebidlParse<&'a webidl::ast::NonPartialInterface> for webidl::ast::Exte
         match self {
             webidl::ast::ExtendedAttribute::ArgumentList(
                 webidl::ast::ArgumentListExtendedAttribute { arguments, name },
-            ) if name == "Constructor" =>
+            )
+                if name == "Constructor" =>
             {
                 add_constructor(arguments, &interface.name)
             }
@@ -358,7 +359,8 @@ impl<'a> WebidlParse<&'a webidl::ast::NonPartialInterface> for webidl::ast::Exte
                     rhs_arguments,
                     rhs_name,
                 },
-            ) if lhs_name == "NamedConstructor" =>
+            )
+                if lhs_name == "NamedConstructor" =>
             {
                 add_constructor(rhs_arguments, rhs_name)
             }
@@ -389,9 +391,11 @@ impl<'a> WebidlParse<&'a str> for webidl::ast::InterfaceMember {
             webidl::ast::InterfaceMember::Operation(op) => {
                 op.webidl_parse(program, first_pass, self_name)
             }
+            webidl::ast::InterfaceMember::Const(cnst) => {
+                cnst.webidl_parse(program, first_pass, self_name)
+            }
             // TODO
-            webidl::ast::InterfaceMember::Const(_)
-            | webidl::ast::InterfaceMember::Iterable(_)
+            webidl::ast::InterfaceMember::Iterable(_)
             | webidl::ast::InterfaceMember::Maplike(_)
             | webidl::ast::InterfaceMember::Setlike(_) => {
                 warn!("Unsupported WebIDL interface member: {:?}", self);
@@ -637,3 +641,29 @@ impl<'a> WebidlParse<()> for webidl::ast::Enum {
         Ok(())
     }
 }
+
+impl<'a> WebidlParse<&'a str> for webidl::ast::Const {
+    fn webidl_parse(
+        &self,
+        program: &mut backend::ast::Program,
+        _: &FirstPassRecord<'_>,
+        interface_name: &'a str,
+    ) -> Result<()> {
+        let syn_ty = webidl_const_ty_to_syn_ty(&self.type_);
+        program.imports.push(backend::ast::Import {
+            module: None,
+            version: None,
+            js_namespace: None,
+            kind: backend::ast::ImportKind::Const(backend::ast::Const {
+                vis: syn::Visibility::Public(syn::VisPublic {
+                    pub_token: Default::default(),
+                }),
+                name: rust_ident(self.name.to_shouty_snake_case().as_str()),
+                interface_name: rust_ident(interface_name.to_camel_case().as_str()),
+                ty: syn_ty,
+                value: webidl_const_v_to_backend_const_v(&self.value),
+            }),
+        });
+        Ok(())
+    }
+}
diff --git a/crates/webidl/src/util.rs b/crates/webidl/src/util.rs
index 2eec7b07..93c7d050 100644
--- a/crates/webidl/src/util.rs
+++ b/crates/webidl/src/util.rs
@@ -19,6 +19,35 @@ fn shared_ref(ty: syn::Type) -> syn::Type {
     }.into()
 }
 
+pub fn webidl_const_ty_to_syn_ty(ty: &webidl::ast::ConstType) -> syn::Type {
+    use webidl::ast::ConstType::*;
+
+    // similar to webidl_ty_to_syn_ty
+    match ty {
+        Boolean => ident_ty(raw_ident("bool")),
+        Byte => ident_ty(raw_ident("i8")),
+        Octet => ident_ty(raw_ident("u8")),
+        RestrictedDouble | UnrestrictedDouble => ident_ty(raw_ident("f64")),
+        RestrictedFloat | UnrestrictedFloat => ident_ty(raw_ident("f32")),
+        SignedLong => ident_ty(raw_ident("i32")),
+        SignedLongLong => ident_ty(raw_ident("i64")),
+        SignedShort => ident_ty(raw_ident("i16")),
+        UnsignedLong => ident_ty(raw_ident("u32")),
+        UnsignedLongLong => ident_ty(raw_ident("u64")),
+        UnsignedShort => ident_ty(raw_ident("u16")),
+        Identifier(ref id) => ident_ty(rust_ident(id)),
+    }
+}
+
+pub fn webidl_const_v_to_backend_const_v(v: &webidl::ast::ConstValue) -> backend::ast::ConstValue {
+    match *v {
+        webidl::ast::ConstValue::BooleanLiteral(b) => backend::ast::ConstValue::BooleanLiteral(b),
+        webidl::ast::ConstValue::FloatLiteral(f) => backend::ast::ConstValue::FloatLiteral(f),
+        webidl::ast::ConstValue::IntegerLiteral(i) => backend::ast::ConstValue::IntegerLiteral(i),
+        webidl::ast::ConstValue::Null => backend::ast::ConstValue::Null,
+    }
+}
+
 fn simple_fn_arg(ident: Ident, ty: syn::Type) -> syn::ArgCaptured {
     syn::ArgCaptured {
         pat: syn::Pat::Ident(syn::PatIdent {
diff --git a/crates/webidl/tests/all/consts.rs b/crates/webidl/tests/all/consts.rs
new file mode 100644
index 00000000..716fbe8a
--- /dev/null
+++ b/crates/webidl/tests/all/consts.rs
@@ -0,0 +1,190 @@
+use super::project;
+
+#[test]
+fn bool() {
+    project()
+        .file(
+            "foo.webidl",
+            r#"
+                interface Foo {
+                    const boolean not_true = false;
+                    const boolean not_false = true;
+                };
+            "#,
+        )
+        // a corresponding const in the js implementation is not required
+        // value is taken directly from idl
+        .file(
+            "foo.js",
+            r#"
+                export class Foo {
+                }
+            "#,
+        )
+        .file(
+            "src/lib.rs",
+            r#"
+                #![feature(proc_macro, wasm_custom_section, wasm_import_module)]
+                extern crate wasm_bindgen;
+                use wasm_bindgen::prelude::*;
+
+                pub mod foo;
+                use foo::Foo;
+
+                #[wasm_bindgen]
+                pub fn test() {
+                    let falsish: bool = Foo::NOT_TRUE;
+                    assert!(!falsish);
+                    let trueish: bool = Foo::NOT_FALSE;
+                    assert!(trueish);
+                }
+            "#,
+        )
+        .test();
+}
+
+#[test]
+fn ints() {
+    project()
+        .file(
+            "foo.webidl",
+            r#"
+                interface Byte {
+                    const byte imin = -128;
+                    const byte imax = 127;
+                    const octet umin = 0;
+                    const octet umax = 255;
+                };
+                interface Short {
+                    const short imin = -32768;
+                    const short imax = 32767;
+                    const unsigned short umin = 0;
+                    const unsigned short umax = 65535;
+                };
+                interface Long {
+                    const long imin = -2147483648;
+                    const long imax = 2147483647;
+                    const unsigned long umin = 0;
+                    const unsigned long umax = 4294967295;
+                };
+                interface LongLong {
+                    const long long imin = -9223372036854775808;
+                    const long long imax = 9223372036854775807;
+                    const unsigned long long umin = 0;
+                    // bug in webidl
+                    // https://github.com/sgodwincs/webidl-rs/issues/15
+                    //const unsigned long long umax = 18446744073709551615;
+                };
+            "#,
+        )
+        // a corresponding const in the js implementation is not required
+        // value is taken directly from idl
+        .file(
+            "foo.js",
+            r#"
+                export class Byte {
+                }
+                export class Short {
+                }
+                export class Long {
+                }
+                export class LongLong {
+                }
+            "#,
+        )
+        .file(
+            "src/lib.rs",
+            r#"
+                #![feature(proc_macro, wasm_custom_section, wasm_import_module)]
+                extern crate wasm_bindgen;
+                use wasm_bindgen::prelude::*;
+
+                pub mod foo;
+
+                #[wasm_bindgen]
+                pub fn test() {
+                    assert_eq!(foo::Byte::IMIN, i8::min_value());
+                    assert_eq!(foo::Byte::IMAX, i8::max_value());
+                    assert_eq!(foo::Byte::UMIN, u8::min_value());
+                    assert_eq!(foo::Byte::UMAX, u8::max_value());
+
+                    assert_eq!(foo::Short::IMIN, i16::min_value());
+                    assert_eq!(foo::Short::IMAX, i16::max_value());
+                    assert_eq!(foo::Short::UMIN, u16::min_value());
+                    assert_eq!(foo::Short::UMAX, u16::max_value());
+
+                    assert_eq!(foo::Long::IMIN, i32::min_value());
+                    assert_eq!(foo::Long::IMAX, i32::max_value());
+                    assert_eq!(foo::Long::UMIN, u32::min_value());
+                    assert_eq!(foo::Long::UMAX, u32::max_value());
+
+                    assert_eq!(foo::LongLong::IMIN, i64::min_value());
+                    assert_eq!(foo::LongLong::IMAX, i64::max_value());
+                    assert_eq!(foo::LongLong::UMIN, u64::min_value());
+                    //assert_eq!(foo::LongLong::UMAX, u64::max_value());
+                }
+            "#,
+        )
+        .test();
+}
+
+#[test]
+fn floats() {
+    project()
+        .file(
+            "foo.webidl",
+            r#"
+                interface floats {
+                    const float f = 0.0;
+                    const unrestricted float neg_inf = -Infinity;
+                    const unrestricted float inf = Infinity;
+                    const unrestricted float nan = NaN;
+                };
+                interface doubles {
+                    const double d = 0.0;
+                    const unrestricted double neg_inf = -Infinity;
+                    const unrestricted double inf = Infinity;
+                    const unrestricted double nan = NaN;
+                };
+            "#,
+        )
+        // a corresponding const in the js implementation is not required
+        // value is taken directly from idl
+        .file(
+            "foo.js",
+            r#"
+                export class floats {
+                }
+                export class doubles {
+                }
+            "#,
+        )
+        .file(
+            "src/lib.rs",
+            r#"
+                #![feature(proc_macro, wasm_custom_section, wasm_import_module)]
+                extern crate wasm_bindgen;
+                use wasm_bindgen::prelude::*;
+
+                pub mod foo;
+
+                #[wasm_bindgen]
+                pub fn test() {
+                    assert_eq!(foo::Floats::F, 0.0_f32);
+                    assert!(foo::Floats::NEG_INF.is_infinite());
+                    assert!(foo::Floats::NEG_INF.is_sign_negative());
+                    assert!(foo::Floats::INF.is_infinite());
+                    assert!(foo::Floats::INF.is_sign_positive());
+                    assert!(foo::Floats::NAN.is_nan());
+
+                    assert_eq!(foo::Doubles::D, 0.0_f64);
+                    assert!(foo::Doubles::NEG_INF.is_infinite());
+                    assert!(foo::Doubles::NEG_INF.is_sign_negative());
+                    assert!(foo::Doubles::INF.is_infinite());
+                    assert!(foo::Doubles::INF.is_sign_positive());
+                    assert!(foo::Doubles::NAN.is_nan());
+                }
+            "#,
+        )
+        .test();
+}
diff --git a/crates/webidl/tests/all/main.rs b/crates/webidl/tests/all/main.rs
index 13a6f789..3815c632 100644
--- a/crates/webidl/tests/all/main.rs
+++ b/crates/webidl/tests/all/main.rs
@@ -1,6 +1,7 @@
 extern crate wasm_bindgen_test_project_builder as project_builder;
 use project_builder::project;
 
-mod simple;
+mod consts;
 mod enums;
+mod simple;
 mod throws;
diff --git a/guide/src/contributing.md b/guide/src/contributing.md
index dbf4f6f5..62d2f222 100644
--- a/guide/src/contributing.md
+++ b/guide/src/contributing.md
@@ -14,7 +14,7 @@ development.
 
 [install Rust]: https://www.rust-lang.org/en-US/install.html
 
-2. The tests for this project use Node. Make sure you have node >= 8 installed,
+2. The tests for this project use Node. Make sure you have node >= 10 installed,
    as that is when WebAssembly support was introduced. [Install Node].
 
 [Install Node]: https://nodejs.org/en/
diff --git a/package.json b/package.json
index 274915ec..51645974 100644
--- a/package.json
+++ b/package.json
@@ -9,13 +9,13 @@
   },
   "devDependencies": {
     "@types/node": "^10.5.2",
-    "babel-eslint": "^8.2.5",
+    "babel-eslint": "^8.2.6",
     "eslint": "^5.1.0",
     "geckodriver": "^1.11.0",
     "selenium-webdriver": "^4.0.0-alpha.1",
     "ts-loader": "^4.4.2",
     "typescript": "^2.7.2",
-    "webpack": "^4.15.1",
+    "webpack": "^4.16.0",
     "webpack-cli": "^3.0.8",
     "webpack-dev-server": "^3.1.4"
   }
diff --git a/src/convert.rs b/src/convert.rs
index c73a553f..65e652cd 100644
--- a/src/convert.rs
+++ b/src/convert.rs
@@ -77,7 +77,6 @@ pub trait RefMutFromWasmAbi: WasmDescribe {
 
 pub trait Stack {
     fn push(&mut self, bits: u32);
-    fn pop(&mut self) -> u32;
 }
 
 /// An unsafe trait which represents types that are ABI-safe to pass via wasm
@@ -105,11 +104,15 @@ macro_rules! simple {
     ($($t:tt)*) => ($(
         impl IntoWasmAbi for $t {
             type Abi = $t;
+
+            #[inline]
             fn into_abi(self, _extra: &mut Stack) -> $t { self }
         }
 
         impl FromWasmAbi for $t {
             type Abi = $t;
+
+            #[inline]
             unsafe fn from_abi(js: $t, _extra: &mut Stack) -> $t { js }
         }
     )*)
@@ -121,6 +124,8 @@ macro_rules! sixtyfour {
     ($($t:tt)*) => ($(
         impl IntoWasmAbi for $t {
             type Abi = WasmSlice;
+
+            #[inline]
             fn into_abi(self, _extra: &mut Stack) -> WasmSlice {
                 WasmSlice {
                     ptr: self as u32,
@@ -131,6 +136,8 @@ macro_rules! sixtyfour {
 
         impl FromWasmAbi for $t {
             type Abi = WasmSlice;
+
+            #[inline]
             unsafe fn from_abi(js: WasmSlice, _extra: &mut Stack) -> $t {
                 (js.ptr as $t) | ((js.len as $t) << 32)
             }
@@ -144,11 +151,15 @@ macro_rules! as_u32 {
     ($($t:tt)*) => ($(
         impl IntoWasmAbi for $t {
             type Abi = u32;
+
+            #[inline]
             fn into_abi(self, _extra: &mut Stack) -> u32 { self as u32 }
         }
 
         impl FromWasmAbi for $t {
             type Abi = u32;
+
+            #[inline]
             unsafe fn from_abi(js: u32, _extra: &mut Stack) -> $t { js as $t }
         }
     )*)
@@ -159,6 +170,7 @@ as_u32!(i8 u8 i16 u16 isize usize);
 impl IntoWasmAbi for bool {
     type Abi = u32;
 
+    #[inline]
     fn into_abi(self, _extra: &mut Stack) -> u32 {
         self as u32
     }
@@ -167,6 +179,7 @@ impl IntoWasmAbi for bool {
 impl FromWasmAbi for bool {
     type Abi = u32;
 
+    #[inline]
     unsafe fn from_abi(js: u32, _extra: &mut Stack) -> bool {
         js != 0
     }
@@ -174,6 +187,8 @@ impl FromWasmAbi for bool {
 
 impl IntoWasmAbi for char {
     type Abi = u32;
+
+    #[inline]
     fn into_abi(self, _extra: &mut Stack) -> u32 {
         self as u32
     }
@@ -181,6 +196,8 @@ impl IntoWasmAbi for char {
 
 impl FromWasmAbi for char {
     type Abi = u32;
+
+    #[inline]
     unsafe fn from_abi(js: u32, _extra: &mut Stack) -> char {
         char::from_u32_unchecked(js)
     }
@@ -224,6 +241,7 @@ macro_rules! vectors {
         impl IntoWasmAbi for Box<[$t]> {
             type Abi = WasmSlice;
 
+            #[inline]
             fn into_abi(self, extra: &mut Stack) -> WasmSlice {
                 let ptr = self.as_ptr();
                 let len = self.len();
@@ -239,6 +257,7 @@ macro_rules! vectors {
         impl FromWasmAbi for Box<[$t]> {
             type Abi = WasmSlice;
 
+            #[inline]
             unsafe fn from_abi(js: WasmSlice, extra: &mut Stack) -> Self {
                 let ptr = <*mut $t>::from_abi(js.ptr, extra);
                 let len = js.len as usize;
@@ -249,6 +268,7 @@ macro_rules! vectors {
         impl<'a> IntoWasmAbi for &'a [$t] {
             type Abi = WasmSlice;
 
+            #[inline]
             fn into_abi(self, extra: &mut Stack) -> WasmSlice {
                 WasmSlice {
                     ptr: self.as_ptr().into_abi(extra),
@@ -260,6 +280,7 @@ macro_rules! vectors {
         impl<'a> IntoWasmAbi for &'a mut [$t] {
             type Abi = WasmSlice;
 
+            #[inline]
             fn into_abi(self, extra: &mut Stack) -> WasmSlice {
                 (&*self).into_abi(extra)
             }
@@ -269,6 +290,7 @@ macro_rules! vectors {
             type Abi = WasmSlice;
             type Anchor = &'static [$t];
 
+            #[inline]
             unsafe fn ref_from_abi(js: WasmSlice, extra: &mut Stack) -> &'static [$t] {
                 slice::from_raw_parts(
                     <*const $t>::from_abi(js.ptr, extra),
@@ -281,6 +303,7 @@ macro_rules! vectors {
             type Abi = WasmSlice;
             type Anchor = &'static mut [$t];
 
+            #[inline]
             unsafe fn ref_mut_from_abi(js: WasmSlice, extra: &mut Stack)
                 -> &'static mut [$t]
             {
@@ -300,6 +323,7 @@ vectors! {
 if_std! {
     impl<T> IntoWasmAbi for Vec<T> where Box<[T]>: IntoWasmAbi {
         type Abi = <Box<[T]> as IntoWasmAbi>::Abi;
+
         fn into_abi(self, extra: &mut Stack) -> Self::Abi {
             self.into_boxed_slice().into_abi(extra)
         }
@@ -316,6 +340,7 @@ if_std! {
     impl IntoWasmAbi for String {
         type Abi = <Vec<u8> as IntoWasmAbi>::Abi;
 
+        #[inline]
         fn into_abi(self, extra: &mut Stack) -> Self::Abi {
             self.into_bytes().into_abi(extra)
         }
@@ -324,6 +349,7 @@ if_std! {
     impl FromWasmAbi for String {
         type Abi = <Vec<u8> as FromWasmAbi>::Abi;
 
+        #[inline]
         unsafe fn from_abi(js: Self::Abi, extra: &mut Stack) -> Self {
             String::from_utf8_unchecked(<Vec<u8>>::from_abi(js, extra))
         }
@@ -333,6 +359,7 @@ if_std! {
 impl<'a> IntoWasmAbi for &'a str {
     type Abi = <&'a [u8] as IntoWasmAbi>::Abi;
 
+    #[inline]
     fn into_abi(self, extra: &mut Stack) -> Self::Abi {
         self.as_bytes().into_abi(extra)
     }
@@ -342,6 +369,7 @@ impl RefFromWasmAbi for str {
     type Abi = <[u8] as RefFromWasmAbi>::Abi;
     type Anchor = &'static str;
 
+    #[inline]
     unsafe fn ref_from_abi(js: Self::Abi, extra: &mut Stack) -> Self::Anchor {
         str::from_utf8_unchecked(<[u8]>::ref_from_abi(js, extra))
     }
@@ -350,6 +378,7 @@ impl RefFromWasmAbi for str {
 impl IntoWasmAbi for JsValue {
     type Abi = u32;
 
+    #[inline]
     fn into_abi(self, _extra: &mut Stack) -> u32 {
         let ret = self.idx;
         mem::forget(self);
@@ -360,6 +389,7 @@ impl IntoWasmAbi for JsValue {
 impl FromWasmAbi for JsValue {
     type Abi = u32;
 
+    #[inline]
     unsafe fn from_abi(js: u32, _extra: &mut Stack) -> JsValue {
         JsValue { idx: js }
     }
@@ -367,6 +397,8 @@ impl FromWasmAbi for JsValue {
 
 impl<'a> IntoWasmAbi for &'a JsValue {
     type Abi = u32;
+
+    #[inline]
     fn into_abi(self, _extra: &mut Stack) -> u32 {
         self.idx
     }
@@ -376,6 +408,7 @@ impl RefFromWasmAbi for JsValue {
     type Abi = u32;
     type Anchor = ManuallyDrop<JsValue>;
 
+    #[inline]
     unsafe fn ref_from_abi(js: u32, _extra: &mut Stack) -> Self::Anchor {
         ManuallyDrop::new(JsValue { idx: js })
     }
@@ -385,6 +418,7 @@ if_std! {
     impl IntoWasmAbi for Box<[JsValue]> {
         type Abi = WasmSlice;
 
+        #[inline]
         fn into_abi(self, extra: &mut Stack) -> WasmSlice {
             let ptr = self.as_ptr();
             let len = self.len();
@@ -399,6 +433,7 @@ if_std! {
     impl FromWasmAbi for Box<[JsValue]> {
         type Abi = WasmSlice;
 
+        #[inline]
         unsafe fn from_abi(js: WasmSlice, extra: &mut Stack) -> Self {
             let ptr = <*mut JsValue>::from_abi(js.ptr, extra);
             let len = js.len as usize;
@@ -415,12 +450,14 @@ const GLOBAL_STACK_CAP: usize = 16;
 static mut GLOBAL_STACK: [u32; GLOBAL_STACK_CAP] = [0; GLOBAL_STACK_CAP];
 
 impl GlobalStack {
+    #[inline]
     pub unsafe fn new() -> GlobalStack {
         GlobalStack { next: 0 }
     }
 }
 
 impl Stack for GlobalStack {
+    #[inline]
     fn push(&mut self, val: u32) {
         unsafe {
             assert!(self.next < GLOBAL_STACK_CAP);
@@ -428,15 +465,6 @@ impl Stack for GlobalStack {
             self.next += 1;
         }
     }
-
-    fn pop(&mut self) -> u32 {
-        unsafe {
-            assert!(self.next < GLOBAL_STACK_CAP);
-            let ret = GLOBAL_STACK[self.next];
-            self.next += 1;
-            ret
-        }
-    }
 }
 
 #[doc(hidden)]
diff --git a/src/js.rs b/src/js.rs
index 208ffe87..33524bd2 100644
--- a/src/js.rs
+++ b/src/js.rs
@@ -240,6 +240,20 @@ extern "C" {
     #[wasm_bindgen(method)]
     pub fn push(this: &Array, value: JsValue) -> u32;
 
+    /// The reduce() method applies a function against an accumulator and each element in 
+    /// the array (from left to right) to reduce it to a single value.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce
+    #[wasm_bindgen(method)]
+    pub fn reduce(this: &Array, predicate: &mut FnMut(JsValue, JsValue, u32, Array) -> JsValue, initial_value: JsValue) -> JsValue;
+
+    /// The reduceRight() method applies a function against an accumulator and each value 
+    /// of the array (from right-to-left) to reduce it to a single value.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/ReduceRight
+    #[wasm_bindgen(method, js_name = reduceRight)]
+    pub fn reduce_right(this: &Array, predicate: &mut FnMut(JsValue, JsValue, u32, Array) -> JsValue, initial_value: JsValue) -> JsValue;
+
     /// The reverse() method reverses an array in place. The first array
     /// element becomes the last, and the last array element becomes the first.
     ///
@@ -378,6 +392,152 @@ extern "C" {
     pub fn value_of(this: &Boolean) -> bool;
 }
 
+// DataView
+#[wasm_bindgen]
+extern "C" {
+    pub type DataView;
+
+    /// The `DataView` view provides a low-level interface for reading and 
+    /// writing multiple number types in an `ArrayBuffer` irrespective of the
+    /// platform's endianness.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView
+    #[wasm_bindgen(constructor)]
+    pub fn new(buffer: &ArrayBuffer, byteOffset: usize, byteLength: usize) -> DataView;
+
+    /// The ArrayBuffer referenced by this view. Fixed at construction time and thus read only.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/buffer
+    #[wasm_bindgen(method, getter, structural)]
+    pub fn buffer(this: &DataView) -> ArrayBuffer;
+
+    /// The length (in bytes) of this view from the start of its ArrayBuffer.
+    /// Fixed at construction time and thus read only.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/byteLength
+    #[wasm_bindgen(method, getter, structural, js_name = byteLength)]
+    pub fn byte_length(this: &DataView) -> usize;
+
+    /// The offset (in bytes) of this view from the start of its ArrayBuffer.
+    /// Fixed at construction time and thus read only.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/byteOffset
+    #[wasm_bindgen(method, getter, structural, js_name = byteOffset)]
+    pub fn byte_offset(this: &DataView) -> usize;
+
+    /// The getInt8() method gets a signed 8-bit integer (byte) at the 
+    /// specified byte offset from the start of the DataView.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getInt8
+    #[wasm_bindgen(method, js_name = getInt8)]
+    pub fn get_int8(this: &DataView, byte_offset: usize) -> i8;
+
+    /// The getUint8() method gets a unsigned 8-bit integer (byte) at the specified
+    /// byte offset from the start of the DataView.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getUint8
+    #[wasm_bindgen(method, js_name = getUint8)]
+    pub fn get_uint8(this: &DataView, byte_offset: usize) -> u8;
+
+    /// The getInt16() method gets a signed 16-bit integer (byte) at the specified
+    /// byte offset from the start of the DataView.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getInt16
+    #[wasm_bindgen(method, js_name = getInt16)]
+    pub fn get_int16(this: &DataView, byte_offset: usize) -> i16;
+
+    /// The getUint16() an unsigned 16-bit integer (unsigned byte) at the specified
+    /// byte offset from the start of the view.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getUint16
+    #[wasm_bindgen(method, js_name = getUint16)]
+    pub fn get_uint16(this: &DataView, byte_offset: usize) -> u16;
+
+    /// The getInt32() method gets a signed 16-bit integer (byte) at the specified
+    /// byte offset from the start of the DataView.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getInt32
+    #[wasm_bindgen(method, js_name = getInt32)]
+    pub fn get_int32(this: &DataView, byte_offset: usize) -> i32;
+
+    /// The getUint32() an unsigned 16-bit integer (unsigned byte) at the specified
+    /// byte offset from the start of the view.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getUint32
+    #[wasm_bindgen(method, js_name = getUint32)]
+    pub fn get_uint32(this: &DataView, byte_offset: usize) -> u32;
+
+    /// The getFloat32() method gets a signed 32-bit float (float) at the specified 
+    /// byte offset from the start of the DataView.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getFloat32
+    #[wasm_bindgen(method, js_name = getFloat32)]
+    pub fn get_float32(this: &DataView, byte_offset: usize) -> f32;
+
+    /// The getFloat64() method gets a signed 32-bit float (float) at the specified 
+    /// byte offset from the start of the DataView.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/getFloat64
+    #[wasm_bindgen(method, js_name = getFloat64)]
+    pub fn get_float64(this: &DataView, byte_offset: usize) -> f64;
+
+    /// The setInt8() method stores a signed 8-bit integer (byte) value at the
+    /// specified byte offset from the start of the DataView.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setInt8
+    #[wasm_bindgen(method, js_name = setInt8)]
+    pub fn set_int8(this: &DataView, byte_offset: usize, value: i8);
+
+    /// The setUint8() method stores an unsigned 8-bit integer (byte) value at the
+    /// specified byte offset from the start of the DataView.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setUint8
+    #[wasm_bindgen(method, js_name = setUint8)]
+    pub fn set_uint8(this: &DataView, byte_offset: usize, value: u8);
+
+    /// The setInt16() method stores a signed 16-bit integer (byte) value at the
+    /// specified byte offset from the start of the DataView.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setInt16
+    #[wasm_bindgen(method, js_name = setInt16)]
+    pub fn set_int16(this: &DataView, byte_offset: usize, value: i16);
+
+    /// The setUint16() method stores an unsigned 16-bit integer (byte) value at the
+    /// specified byte offset from the start of the DataView.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setUint16
+    #[wasm_bindgen(method, js_name = setUint16)]
+    pub fn set_uint16(this: &DataView, byte_offset: usize, value: u16);
+
+    /// The setInt32() method stores a signed 32-bit integer (byte) value at the
+    /// specified byte offset from the start of the DataView.
+    ///
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setInt32
+    #[wasm_bindgen(method, js_name = setInt32)]
+    pub fn set_int32(this: &DataView, byte_offset: usize, value: i32);
+
+    /// The setUint32() method stores an unsigned 32-bit integer (byte) value at the
+    /// specified byte offset from the start of the DataView.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setUint32
+    #[wasm_bindgen(method, js_name = setUint32)]
+    pub fn set_uint32(this: &DataView, byte_offset: usize, value: u32);
+
+    /// The setFloat32() method stores a signed 32-bit float (float) value at the 
+    /// specified byte offset from the start of the DataView.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setFloat32
+    #[wasm_bindgen(method, js_name = setFloat32)]
+    pub fn set_float32(this: &DataView, byte_offset: usize, value: f32);
+
+    /// The setFloat64() method stores a signed 64-bit float (float) value at the 
+    /// specified byte offset from the start of the DataView.
+    /// 
+    /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/setFloat64
+    #[wasm_bindgen(method, js_name = setFloat64)]
+    pub fn set_float64(this: &DataView, byte_offset: usize, value: f64);
+}
+
 // Error
 #[wasm_bindgen]
 extern "C" {
diff --git a/src/lib.rs b/src/lib.rs
index a43a8d80..ee2d19c6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,7 +5,7 @@
 //! this crate and this crate also provides JS bindings through the `JsValue`
 //! interface.
 
-#![feature(use_extern_macros, wasm_import_module, try_reserve, unsize)]
+#![feature(use_extern_macros, wasm_import_module, unsize)]
 #![cfg_attr(feature = "js_globals", feature(proc_macro, wasm_custom_section))]
 #![no_std]
 
@@ -661,24 +661,29 @@ pub mod __rt {
     }
 
     if_std! {
-        use std::prelude::v1::*;
+        use std::alloc::{System, GlobalAlloc, Layout};
+        use std::mem;
 
         #[no_mangle]
         pub extern fn __wbindgen_malloc(size: usize) -> *mut u8 {
-            use core::mem;
-
-            let mut ret = Vec::new();
-            if ret.try_reserve_exact(size).is_err() {
-                super::throw("invalid malloc request");
+            let align = mem::align_of::<usize>();
+            if let Ok(layout) = Layout::from_size_align(size, align) {
+                unsafe {
+                    let ptr = System.alloc(layout);
+                    if !ptr.is_null() {
+                        return ptr
+                    }
+                }
             }
-            let ptr = ret.as_mut_ptr();
-            mem::forget(ret);
-            return ptr
+
+            super::throw("invalid malloc request");
         }
 
         #[no_mangle]
         pub unsafe extern fn __wbindgen_free(ptr: *mut u8, size: usize) {
-            drop(Vec::<u8>::from_raw_parts(ptr, 0, size));
+            let align = mem::align_of::<usize>();
+            let layout = Layout::from_size_align_unchecked(size, align);
+            System.dealloc(ptr, layout);
         }
     }
 
diff --git a/tests/all/js_globals/Array.rs b/tests/all/js_globals/Array.rs
index a8ab5477..c9a0d55b 100644
--- a/tests/all/js_globals/Array.rs
+++ b/tests/all/js_globals/Array.rs
@@ -830,3 +830,69 @@ fn map() {
         )
         .test()
 }
+
+#[test]
+fn reduce() {
+    project()
+        .file(
+            "src/lib.rs",
+            r#"
+                #![feature(proc_macro, wasm_custom_section)]
+
+                extern crate wasm_bindgen;
+                use wasm_bindgen::prelude::*;
+                use wasm_bindgen::js;
+                use JsValue;
+
+                #[wasm_bindgen]
+                pub fn array_reduce(array: &js::Array) -> JsValue {
+                    array.reduce(&mut |ac, cr, _, _| JsValue::from_str(&format!("{}{}", &ac.as_string().unwrap(), &cr.as_string().unwrap().as_str())), JsValue::from_str(""))
+                }
+            "#,
+        )
+        .file(
+            "test.js",
+            r#"
+                import * as assert from "assert";
+                import * as wasm from "./out";
+
+                export function test() {
+                    assert.equal(wasm.array_reduce(['0', '1', '2', '3', '4']), '01234');
+                }
+            "#,
+        )
+        .test()
+}
+
+#[test]
+fn reduce_right() {
+    project()
+        .file(
+            "src/lib.rs",
+            r#"
+                #![feature(proc_macro, wasm_custom_section)]
+
+                extern crate wasm_bindgen;
+                use wasm_bindgen::prelude::*;
+                use wasm_bindgen::js;
+                use JsValue;
+
+                #[wasm_bindgen]
+                pub fn array_reduce_right(array: &js::Array) -> JsValue {
+                    array.reduce_right(&mut |ac, cr, _, _| JsValue::from_str(&format!("{}{}", &ac.as_string().unwrap(), &cr.as_string().unwrap().as_str())), JsValue::from_str(""))
+                }
+            "#,
+        )
+        .file(
+            "test.js",
+            r#"
+                import * as assert from "assert";
+                import * as wasm from "./out";
+
+                export function test() {
+                    assert.equal(wasm.array_reduce_right(['0', '1', '2', '3', '4']), '43210');
+                }
+            "#,
+        )
+        .test()
+}
\ No newline at end of file
diff --git a/tests/all/js_globals/DataView.rs b/tests/all/js_globals/DataView.rs
new file mode 100644
index 00000000..ced10a22
--- /dev/null
+++ b/tests/all/js_globals/DataView.rs
@@ -0,0 +1,55 @@
+#![allow(non_snake_case)]
+
+use super::project;
+
+#[test]
+fn test() {
+    project()
+        .file("src/lib.rs", r#"
+            #![feature(proc_macro, wasm_custom_section)]
+
+            extern crate wasm_bindgen;
+            use wasm_bindgen::prelude::*;
+            use wasm_bindgen::js::{ArrayBuffer, DataView};
+
+            #[wasm_bindgen]
+            pub fn test_data_view(buffer: &ArrayBuffer, offset: usize, len: usize) {
+                let v = DataView::new(buffer, offset, len);
+                assert_eq!(v.byte_offset(), offset);
+                assert_eq!(v.byte_length(), len);
+                assert_eq!(v.get_int8(0), 2);
+                assert_eq!(v.get_uint8(0), 2);
+                
+                v.set_int8(0, 42);
+                assert_eq!(v.get_int8(0), 42);
+                v.set_uint8(0, 255);
+                assert_eq!(v.get_uint8(0), 255);
+                v.set_int16(0, 32767);
+                assert_eq!(v.get_int16(0), 32767);
+                v.set_uint16(0, 65535);
+                assert_eq!(v.get_uint16(0), 65535);
+                v.set_int32(0, 123456789);
+                assert_eq!(v.get_int32(0), 123456789);
+                v.set_uint32(0, 3_123_456_789);
+                assert_eq!(v.get_uint32(0), 3_123_456_789);
+                v.set_float32(0, 100.123);
+                assert_eq!(v.get_float32(0), 100.123);
+                v.set_float64(0, 123456789.123456);
+                assert_eq!(v.get_float64(0), 123456789.123456);
+
+                v.set_int8(0, 42);
+            }
+        "#)
+        .file("test.js", r#"
+            import * as assert from "assert";
+            import * as wasm from "./out";
+
+            export function test() {
+                const bytes = new Int8Array(10);
+                bytes[2] = 2;
+                wasm.test_data_view(bytes.buffer, 2, 8);
+                assert.equal(bytes[2], 42);
+            }
+        "#)
+        .test()
+}
diff --git a/tests/all/js_globals/mod.rs b/tests/all/js_globals/mod.rs
index 2af15330..211df89e 100644
--- a/tests/all/js_globals/mod.rs
+++ b/tests/all/js_globals/mod.rs
@@ -6,6 +6,7 @@ mod Array;
 mod ArrayBuffer;
 mod ArrayIterator;
 mod Boolean;
+mod DataView;
 mod Date;
 mod Error;
 mod Function;
diff --git a/yarn.lock b/yarn.lock
index 8702f195..2de4b8b2 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -408,15 +408,15 @@ babel-code-frame@^6.26.0:
     esutils "^2.0.2"
     js-tokens "^3.0.2"
 
-babel-eslint@^8.2.5:
-  version "8.2.5"
-  resolved "https://registry.yarnpkg.com/babel-eslint/-/babel-eslint-8.2.5.tgz#dc2331c259d36782aa189da510c43dedd5adc7a3"
+babel-eslint@^8.2.6:
+  version "8.2.6"
+  resolved "https://registry.yarnpkg.com/babel-eslint/-/babel-eslint-8.2.6.tgz#6270d0c73205628067c0f7ae1693a9e797acefd9"
   dependencies:
     "@babel/code-frame" "7.0.0-beta.44"
     "@babel/traverse" "7.0.0-beta.44"
     "@babel/types" "7.0.0-beta.44"
     babylon "7.0.0-beta.44"
-    eslint-scope "~3.7.1"
+    eslint-scope "3.7.1"
     eslint-visitor-keys "^1.0.0"
 
 babylon@7.0.0-beta.44:
@@ -1239,7 +1239,7 @@ escape-string-regexp@^1.0.2, escape-string-regexp@^1.0.5:
   version "1.0.5"
   resolved "https://registry.yarnpkg.com/escape-string-regexp/-/escape-string-regexp-1.0.5.tgz#1b61c0562190a8dff6ae3bb2cf0200ca130b86d4"
 
-eslint-scope@^3.7.1, eslint-scope@~3.7.1:
+eslint-scope@3.7.1, eslint-scope@^3.7.1:
   version "3.7.1"
   resolved "https://registry.yarnpkg.com/eslint-scope/-/eslint-scope-3.7.1.tgz#3d63c3edfda02e06e01a452ad88caacc7cdcb6e8"
   dependencies:
@@ -4150,9 +4150,9 @@ webpack-sources@^1.0.1, webpack-sources@^1.1.0:
     source-list-map "^2.0.0"
     source-map "~0.6.1"
 
-webpack@^4.15.1:
-  version "4.15.1"
-  resolved "https://registry.yarnpkg.com/webpack/-/webpack-4.15.1.tgz#dc716779a3b88827c369f18c71a6137fa7e582fd"
+webpack@^4.16.0:
+  version "4.16.0"
+  resolved "https://registry.yarnpkg.com/webpack/-/webpack-4.16.0.tgz#660dae90890e55b8ed17c6f9d17bebb01dab5b4c"
   dependencies:
     "@webassemblyjs/ast" "1.5.13"
     "@webassemblyjs/helper-module-context" "1.5.13"