diff --git a/.circleci/config.yml b/.circleci/config.yml
index 3490bf6b539..67309e90320 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -21,7 +21,8 @@ jobs:
       - checkout
       - restore_cache:
           keys:
-            - v6-lint-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-lint-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-lint-{{ arch }}
       - <<: *run_install_dependencies
       - run:
           name: Install lint deps
@@ -40,7 +41,7 @@ jobs:
             - target/debug/.fingerprint
             - target/debug/build
             - target/debug/deps
-          key: v6-test-cargo-cache-linux-{{ arch }}-{{ checksum "Cargo.lock" }}
+          key: v8-lint-{{ arch }}-{{ checksum "Cargo.lock" }}
 
   test:
     docker:
@@ -50,14 +51,17 @@ jobs:
       - checkout
       - restore_cache:
           keys:
-            - v6-test-cargo-cache-linux-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-test-cargo-cache-linux-stable-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-test-cargo-cache-linux-stable-{{ arch }}
       - <<: *run_install_dependencies
       - run:
           name: Tests
           command: make test
       - run:
           name: Emscripten Tests
-          command: make test-emscripten
+          command: |
+            make test-emscripten-clif
+            make test-emscripten-llvm
       - run:
           name: Integration Tests
           command: make integration-tests
@@ -67,7 +71,7 @@ jobs:
             - target/debug/.fingerprint
             - target/debug/build
             - target/debug/deps
-          key: v6-test-cargo-cache-linux-{{ arch }}-{{ checksum "Cargo.lock" }}
+          key: v8-test-cargo-cache-linux-stable-{{ arch }}-{{ checksum "Cargo.lock" }}
 
   test-macos:
     macos:
@@ -76,7 +80,8 @@ jobs:
       - checkout
       - restore_cache:
           keys:
-            - v6-cargo-cache-darwin-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-cargo-cache-darwin-stable-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-cargo-cache-darwin-stable-{{ arch }}
       - run:
           name: Install crate dependencies
           command: |
@@ -112,7 +117,8 @@ jobs:
             # We increase the ulimit for fixing cargo unclosed files in mac
             ulimit -n 8000
             sudo sysctl -w kern.maxfiles=655360 kern.maxfilesperproc=327680
-            make test-emscripten
+            make test-emscripten-clif
+            make test-emscripten-llvm
       - run:
           name: Integration Tests
           command: |
@@ -129,7 +135,7 @@ jobs:
             - target/release/.fingerprint
             - target/release/build
             - target/release/deps
-          key: v6-cargo-cache-darwin-{{ arch }}-{{ checksum "Cargo.lock" }}
+          key: v8-cargo-cache-darwin-stable-{{ arch }}-{{ checksum "Cargo.lock" }}
 
   test-and-build:
     docker:
@@ -138,13 +144,16 @@ jobs:
       - checkout
       - restore_cache:
           keys:
-            - v6-cargo-cache-linux-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-cargo-cache-linux-nightly-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-cargo-cache-linux-nightly-{{ arch }}
       - run:
           name: Install dependencies
           command: |
             sudo apt-get install -y cmake
             curl -O https://releases.llvm.org/7.0.0/clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04.tar.xz
             tar xf clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04.tar.xz
+      # Use rust nightly (for singlepass, for now)
+      - run: rustup default nightly-2019-04-11
       - run:
           name: Tests
           command: |
@@ -154,7 +163,8 @@ jobs:
           name: Emscripten Tests
           command: |
             export LLVM_SYS_70_PREFIX="`pwd`/clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04/"
-            make test-emscripten
+            make test-emscripten-clif
+            make test-emscripten-llvm
       - run:
           name: Release Build
           command: |
@@ -183,7 +193,7 @@ jobs:
             - target/release/.fingerprint
             - target/release/build
             - target/release/deps
-          key: v6-cargo-cache-linux-{{ arch }}-{{ checksum "Cargo.lock" }}
+          key: v8-cargo-cache-linux-nightly-{{ arch }}-{{ checksum "Cargo.lock" }}
 
   test-and-build-macos:
     macos:
@@ -192,7 +202,8 @@ jobs:
       - checkout
       - restore_cache:
           keys:
-            - v6-cargo-cache-darwin-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-cargo-cache-darwin-nightly-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-cargo-cache-darwin-nightly-{{ arch }}
       - run:
           name: Install crate dependencies
           command: |
@@ -209,6 +220,8 @@ jobs:
             curl https://sh.rustup.rs -sSf | sh -s -- -y
             export PATH="$HOME/.cargo/bin:$PATH"
             cargo --version
+      # Use rust nightly (for singlepass, for now)
+      - run: rustup default nightly-2019-04-11
       - run:
           name: Tests
           command: |
@@ -228,7 +241,8 @@ jobs:
             # We increase the ulimit for fixing cargo unclosed files in mac
             ulimit -n 8000
             sudo sysctl -w kern.maxfiles=655360 kern.maxfilesperproc=327680
-            make test-emscripten
+            make test-emscripten-clif
+            make test-emscripten-singlepass
       - run:
           name: Release Build
           command: |
@@ -253,7 +267,7 @@ jobs:
             - target/release/.fingerprint
             - target/release/build
             - target/release/deps
-          key: v6-cargo-cache-darwin-{{ arch }}-{{ checksum "Cargo.lock" }}
+          key: v8-cargo-cache-darwin-nightly-{ arch }}-{{ checksum "Cargo.lock" }}
 
   test-rust-nightly:
     docker:
@@ -262,27 +276,28 @@ jobs:
       - checkout
       - restore_cache:
           keys:
-            - v6-test-cargo-cache-linux-{{ arch }}-{{ checksum "Cargo.lock" }}-nightly
+            - v8-cargo-cache-linux-nightly-{{ arch }}-{{ checksum "Cargo.lock" }}
+            - v8-cargo-cache-linux-nightly-{{ arch }}
       - run:
           name: Install dependencies
           command: |
             sudo apt-get install -y cmake
             curl -O https://releases.llvm.org/7.0.0/clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04.tar.xz
             tar xf clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04.tar.xz
-      - run: rustup default nightly-2019-02-27
+      - run: rustup default nightly-2019-04-11
       - run: |
           export LLVM_SYS_70_PREFIX="`pwd`/clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04/"
           make test
-          make test-nightly
+          make test-singlepass
           make test-emscripten-clif
-          make test-emscripten-nightly
+          make test-emscripten-singlepass
       - save_cache:
           paths:
             - /usr/local/cargo/registry
             - target/debug/.fingerprint
             - target/debug/build
             - target/debug/deps
-          key: v6-test-cargo-cache-linux-{{ arch }}-{{ checksum "Cargo.lock" }}-nightly
+          key: v8-cargo-cache-linux-nightly-{{ arch }}-{{ checksum "Cargo.lock" }}-nightly
 
   publish-github-release:
     docker:
diff --git a/Cargo.lock b/Cargo.lock
index a82cca2b353..fec3babbb58 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2230,12 +2230,12 @@ dependencies = [
  "structopt 0.2.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "wabt 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasmer-clif-backend 0.2.0",
- "wasmer-dynasm-backend 0.1.0",
  "wasmer-emscripten 0.2.1",
  "wasmer-llvm-backend 0.1.0",
  "wasmer-runtime 0.2.1",
  "wasmer-runtime-abi 0.2.1",
  "wasmer-runtime-core 0.2.1",
+ "wasmer-singlepass-backend 0.1.0",
  "wasmer-wasi 0.2.1",
 ]
 
@@ -2263,22 +2263,6 @@ dependencies = [
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "wasmer-dynasm-backend"
-version = "0.1.0"
-dependencies = [
- "byteorder 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "dynasm 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "dynasmrt 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "hashbrown 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.51 (registry+https://github.com/rust-lang/crates.io-index)",
- "nix 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "smallvec 0.6.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "wasmer-runtime-core 0.2.1",
- "wasmparser 0.28.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "wasmer-emscripten"
 version = "0.2.1"
@@ -2291,9 +2275,9 @@ dependencies = [
  "time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
  "wabt 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasmer-clif-backend 0.2.0",
- "wasmer-dynasm-backend 0.1.0",
  "wasmer-llvm-backend 0.1.0",
  "wasmer-runtime-core 0.2.1",
+ "wasmer-singlepass-backend 0.1.0",
 ]
 
 [[package]]
@@ -2327,9 +2311,9 @@ dependencies = [
  "tempfile 3.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "wabt 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasmer-clif-backend 0.2.0",
- "wasmer-dynasm-backend 0.1.0",
  "wasmer-llvm-backend 0.1.0",
  "wasmer-runtime-core 0.2.1",
+ "wasmer-singlepass-backend 0.1.0",
 ]
 
 [[package]]
@@ -2382,15 +2366,31 @@ dependencies = [
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "wasmer-singlepass-backend"
+version = "0.1.0"
+dependencies = [
+ "byteorder 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "dynasm 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "dynasmrt 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hashbrown 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.51 (registry+https://github.com/rust-lang/crates.io-index)",
+ "nix 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "smallvec 0.6.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wasmer-runtime-core 0.2.1",
+ "wasmparser 0.28.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "wasmer-spectests"
 version = "0.2.0"
 dependencies = [
  "wabt 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasmer-clif-backend 0.2.0",
- "wasmer-dynasm-backend 0.1.0",
  "wasmer-llvm-backend 0.1.0",
  "wasmer-runtime-core 0.2.1",
+ "wasmer-singlepass-backend 0.1.0",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 244581f8d97..a82a52ef1d9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,7 +24,7 @@ structopt = "0.2.11"
 wabt = "0.7.2"
 hashbrown = "0.1.8"
 wasmer-clif-backend = { path = "lib/clif-backend" }
-wasmer-dynasm-backend = { path = "lib/dynasm-backend", optional = true }
+wasmer-singlepass-backend = { path = "lib/singlepass-backend", optional = true }
 wasmer-runtime = { path = "lib/runtime" }
 wasmer-runtime-abi = { path = "lib/runtime-abi", optional = true }
 wasmer-runtime-core = { path = "lib/runtime-core" }
@@ -33,18 +33,18 @@ wasmer-llvm-backend = { path = "lib/llvm-backend", optional = true }
 wasmer-wasi = { path = "lib/wasi", optional = true }
 
 [workspace]
-members = ["lib/clif-backend", "lib/dynasm-backend", "lib/runtime", "lib/runtime-abi", "lib/runtime-core", "lib/emscripten", "lib/spectests", "lib/win-exception-handler", "lib/runtime-c-api", "lib/llvm-backend", "lib/wasi"]
+members = ["lib/clif-backend", "lib/singlepass-backend", "lib/runtime", "lib/runtime-abi", "lib/runtime-core", "lib/emscripten", "lib/spectests", "lib/win-exception-handler", "lib/runtime-c-api", "lib/llvm-backend", "lib/wasi"]
 
 [build-dependencies]
 wabt = "0.7.2"
 glob = "0.2.11"
 
 [features]
-default = ["fast-tests", "wasi"]
+default = ["fast-tests", "wasi", "singlepass", "llvm"]
 debug = ["wasmer-clif-backend/debug", "wasmer-runtime-core/debug"]
 # This feature will allow cargo test to run much faster
 fast-tests = []
-llvm = ["wasmer-llvm-backend", "wasmer-runtime/llvm"]
-dynasm = ["wasmer-dynasm-backend", "wasmer-runtime/dynasm"]
+llvm = ["wasmer-llvm-backend"]
+singlepass = ["wasmer-singlepass-backend"]
 wasi = ["wasmer-wasi"]
 vfs = ["wasmer-runtime-abi"]
diff --git a/Makefile b/Makefile
index 383d4ccf4ab..2b87dd7e7de 100644
--- a/Makefile
+++ b/Makefile
@@ -34,34 +34,33 @@ precommit: lint test
 
 test:
 	# We use one thread so the emscripten stdouts doesn't collide
-	cargo test --all --exclude wasmer-runtime-c-api --exclude wasmer-emscripten --exclude wasmer-spectests --exclude wasmer-dynasm-backend -- $(runargs)
+	cargo test --all --exclude wasmer-runtime-c-api --exclude wasmer-emscripten --exclude wasmer-spectests --exclude wasmer-singlepass-backend -- $(runargs)
 	# cargo test --all --exclude wasmer-emscripten -- --test-threads=1 $(runargs)
 	cargo test --manifest-path lib/spectests/Cargo.toml --features clif
 	cargo test --manifest-path lib/spectests/Cargo.toml --features llvm
 	cargo build -p wasmer-runtime-c-api
 	cargo test -p wasmer-runtime-c-api -- --nocapture
 
-test-nightly:
-	cargo test --manifest-path lib/spectests/Cargo.toml --features dynasm
+test-singlepass:
+	cargo test --manifest-path lib/spectests/Cargo.toml --features singlepass
 
-test-emscripten:
-	cargo test --manifest-path lib/emscripten/Cargo.toml --features clif -- --test-threads=1 $(runargs)
+test-emscripten-llvm:
 	cargo test --manifest-path lib/emscripten/Cargo.toml --features llvm -- --test-threads=1 $(runargs)
 
 test-emscripten-clif:
 	cargo test --manifest-path lib/emscripten/Cargo.toml --features clif -- --test-threads=1 $(runargs)
 
-test-emscripten-nightly:
-	cargo test --manifest-path lib/emscripten/Cargo.toml --features dynasm -- --test-threads=1 $(runargs)
+test-emscripten-singlepass:
+	cargo test --manifest-path lib/emscripten/Cargo.toml --features singlepass -- --test-threads=1 $(runargs)
 
-dynasm-debug-release:
-	cargo +nightly build --features "dynasm debug" --release
+singlepass-debug-release:
+	cargo +nightly build --features "singlepass debug" --release
 
-dynasm-release:
-	cargo +nightly build --features "dynasm" --release
+singlepass-release:
+	cargo +nightly build --features "singlepass" --release
 
-dynasm-build:
-	cargo +nightly build --features "dynasm debug"
+singlepass-build:
+	cargo +nightly build --features "singlepass debug"
 
 release:
 	# If you are in OS-X, you will need mingw-w64 for cross compiling to windows
diff --git a/lib/README.md b/lib/README.md
index b8a99dd6d68..83a3355886c 100644
--- a/lib/README.md
+++ b/lib/README.md
@@ -34,6 +34,6 @@ to tune the codegen properties (compile speed, performance, etc) to best fit the
 
 Currently, we support multiple backends for compiling WebAssembly to machine code:
 
-- [dynasm-backend](./dynasm-backend/): Dynasm backend - super fast compilation, slower runtime speed
+- [singlepass-backend](./singlepass-backend/): Single pass backend - super fast compilation, slower runtime speed
 - [clif-backend](./clif-backend/): Cranelift backend - slower compilation, normal runtime speed
 - [llvm-backend](./llvm-backend/): LLVM backend - slow compilation, native runtime speed
diff --git a/lib/emscripten/Cargo.toml b/lib/emscripten/Cargo.toml
index 5c59db3506d..8b19340b0a7 100644
--- a/lib/emscripten/Cargo.toml
+++ b/lib/emscripten/Cargo.toml
@@ -15,7 +15,7 @@ libc = "0.2.49"
 byteorder = "1"
 time = "0.1.41"
 wasmer-clif-backend = { path = "../clif-backend", version = "0.2.0" }
-wasmer-dynasm-backend = { path = "../dynasm-backend", version = "0.1.0", optional = true }
+wasmer-singlepass-backend = { path = "../singlepass-backend", version = "0.1.0", optional = true }
 wasmer-llvm-backend = { path = "../llvm-backend", version = "0.1.0", optional = true }
 
 [target.'cfg(windows)'.dependencies]
@@ -30,5 +30,5 @@ glob = "0.2.11"
 [features]
 clif = []
 llvm = ["wasmer-llvm-backend"]
-dynasm = ["wasmer-dynasm-backend"]
+singlepass = ["wasmer-singlepass-backend"]
 debug = ["wasmer-clif-backend/debug", "wasmer-runtime-core/debug"]
diff --git a/lib/emscripten/src/utils.rs b/lib/emscripten/src/utils.rs
index 725f0ba9408..e1cf13ef516 100644
--- a/lib/emscripten/src/utils.rs
+++ b/lib/emscripten/src/utils.rs
@@ -186,13 +186,13 @@ mod tests {
         LLVMCompiler::new()
     }
 
-    #[cfg(feature = "dynasm")]
+    #[cfg(feature = "singlepass")]
     fn get_compiler() -> impl Compiler {
-        use wasmer_dynasm_backend::SinglePassCompiler;
+        use wasmer_singlepass_backend::SinglePassCompiler;
         SinglePassCompiler::new()
     }
 
-    #[cfg(not(any(feature = "llvm", feature = "clif", feature = "dynasm")))]
+    #[cfg(not(any(feature = "llvm", feature = "clif", feature = "singlepass")))]
     fn get_compiler() -> impl Compiler {
         panic!("compiler not specified, activate a compiler via features");
         use wasmer_clif_backend::CraneliftCompiler;
diff --git a/lib/emscripten/tests/emtests/_common.rs b/lib/emscripten/tests/emtests/_common.rs
index ca5f6028265..18664e4eac7 100644
--- a/lib/emscripten/tests/emtests/_common.rs
+++ b/lib/emscripten/tests/emtests/_common.rs
@@ -20,13 +20,13 @@ macro_rules! assert_emscripten_output {
             LLVMCompiler::new()
         }
 
-        #[cfg(feature = "dynasm")]
+        #[cfg(feature = "singlepass")]
         fn get_compiler() -> impl Compiler {
-            use wasmer_dynasm_backend::SinglePassCompiler;
+            use wasmer_singlepass_backend::SinglePassCompiler;
             SinglePassCompiler::new()
         }
 
-        #[cfg(not(any(feature = "llvm", feature = "clif", feature = "dynasm")))]
+        #[cfg(not(any(feature = "llvm", feature = "clif", feature = "singlepass")))]
         fn get_compiler() -> impl Compiler {
             panic!("compiler not specified, activate a compiler via features");
             use wasmer_clif_backend::CraneliftCompiler;
diff --git a/lib/runtime-core/src/backend.rs b/lib/runtime-core/src/backend.rs
index 1e528651d92..1044a7ee56a 100644
--- a/lib/runtime-core/src/backend.rs
+++ b/lib/runtime-core/src/backend.rs
@@ -25,7 +25,7 @@ pub use crate::sig_registry::SigRegistry;
 #[derive(Serialize, Deserialize, Debug, Copy, Clone, PartialEq, Eq)]
 pub enum Backend {
     Cranelift,
-    Dynasm,
+    Singlepass,
     LLVM,
 }
 
diff --git a/lib/runtime/Cargo.toml b/lib/runtime/Cargo.toml
index c137922f063..f34798bf550 100644
--- a/lib/runtime/Cargo.toml
+++ b/lib/runtime/Cargo.toml
@@ -9,7 +9,7 @@ edition = "2018"
 readme = "README.md"
 
 [dependencies]
-wasmer-dynasm-backend = { path = "../dynasm-backend", optional = true }
+wasmer-singlepass-backend = { path = "../singlepass-backend", optional = true }
 lazy_static = "1.2.0"
 memmap = "0.7.0"
 
@@ -37,7 +37,7 @@ default-compiler = ["wasmer-clif-backend"]
 cache = ["default-compiler"]
 debug = ["wasmer-clif-backend/debug", "wasmer-runtime-core/debug"]
 llvm = ["wasmer-llvm-backend"]
-dynasm = ["wasmer-dynasm-backend"]
+singlepass = ["wasmer-singlepass-backend"]
 
 [[bench]]
 name = "nginx"
diff --git a/lib/runtime/src/lib.rs b/lib/runtime/src/lib.rs
index a45faddc1c7..1836bb206be 100644
--- a/lib/runtime/src/lib.rs
+++ b/lib/runtime/src/lib.rs
@@ -141,6 +141,16 @@ pub fn compile_with_config(
     wasmer_runtime_core::compile_with_config(&wasm[..], default_compiler(), compiler_config)
 }
 
+/// The same as `compile_with_config` but takes a `Compiler` for the purpose of
+/// changing the backend.
+pub fn compile_with_config_with(
+    wasm: &[u8],
+    compiler_config: CompilerConfig,
+    compiler: &dyn Compiler,
+) -> error::CompileResult<Module> {
+    wasmer_runtime_core::compile_with_config(&wasm[..], compiler, compiler_config)
+}
+
 /// Compile and instantiate WebAssembly code without
 /// creating a [`Module`].
 ///
@@ -171,10 +181,10 @@ pub fn default_compiler() -> &'static dyn Compiler {
     #[cfg(feature = "llvm")]
     use wasmer_llvm_backend::LLVMCompiler as DefaultCompiler;
 
-    #[cfg(feature = "dynasm")]
-    use wasmer_dynasm_backend::SinglePassCompiler as DefaultCompiler;
+    #[cfg(feature = "singlepass")]
+    use wasmer_singlepass_backend::SinglePassCompiler as DefaultCompiler;
 
-    #[cfg(not(any(feature = "llvm", feature = "dynasm")))]
+    #[cfg(not(any(feature = "llvm", feature = "singlepass")))]
     use wasmer_clif_backend::CraneliftCompiler as DefaultCompiler;
 
     lazy_static! {
diff --git a/lib/dynasm-backend/Cargo.toml b/lib/singlepass-backend/Cargo.toml
similarity index 81%
rename from lib/dynasm-backend/Cargo.toml
rename to lib/singlepass-backend/Cargo.toml
index 3f6ef866720..977a3eac6b0 100644
--- a/lib/dynasm-backend/Cargo.toml
+++ b/lib/singlepass-backend/Cargo.toml
@@ -1,8 +1,8 @@
 [package]
-name = "wasmer-dynasm-backend"
+name = "wasmer-singlepass-backend"
 version = "0.1.0"
 repository = "https://github.com/wasmerio/wasmer"
-description = "Wasmer runtime Dynasm compiler backend"
+description = "Wasmer runtime single pass compiler backend"
 license = "MIT"
 authors = ["The Wasmer Engineering Team <engineering@wasmer.io>"]
 edition = "2018"
diff --git a/lib/dynasm-backend/README.md b/lib/singlepass-backend/README.md
similarity index 68%
rename from lib/dynasm-backend/README.md
rename to lib/singlepass-backend/README.md
index a525cbfac99..3d8c63615f5 100644
--- a/lib/dynasm-backend/README.md
+++ b/lib/singlepass-backend/README.md
@@ -14,18 +14,18 @@
   <a href="https://spectrum.chat/wasmer">
     <img src="https://withspectrum.github.io/badge/badge.svg" alt="Join the Wasmer Community">
   </a>
-  <a href="https://crates.io/crates/wasmer-dynasm-backend">
-    <img src="https://img.shields.io/crates/d/wasmer-dynasm-backend.svg" alt="Number of downloads from crates.io">
+  <a href="https://crates.io/crates/wasmer-singlepass-backend">
+    <img src="https://img.shields.io/crates/d/wasmer-singlepass-backend.svg" alt="Number of downloads from crates.io">
   </a>
-  <a href="https://docs.rs/wasmer-dynasm-backend">
-    <img src="https://docs.rs/wasmer-dynasm-backend/badge.svg" alt="Read our API documentation">
+  <a href="https://docs.rs/wasmer-singlepass-backend">
+    <img src="https://docs.rs/wasmer-singlepass-backend/badge.svg" alt="Read our API documentation">
   </a>
 </p>
 
-# Wasmer dynasm backend
+# Wasmer singlepass backend
 
 Wasmer is a standalone JIT WebAssembly runtime, aiming to be fully
 compatible with Emscripten, Rust and Go. [Learn
 more](https://github.com/wasmerio/wasmer).
 
-This crate represents the dynasm backend.
+This crate represents the singlepass backend.
diff --git a/lib/dynasm-backend/src/codegen.rs b/lib/singlepass-backend/src/codegen.rs
similarity index 100%
rename from lib/dynasm-backend/src/codegen.rs
rename to lib/singlepass-backend/src/codegen.rs
diff --git a/lib/dynasm-backend/src/codegen_x64.rs b/lib/singlepass-backend/src/codegen_x64.rs
similarity index 100%
rename from lib/dynasm-backend/src/codegen_x64.rs
rename to lib/singlepass-backend/src/codegen_x64.rs
diff --git a/lib/dynasm-backend/src/emitter_x64.rs b/lib/singlepass-backend/src/emitter_x64.rs
similarity index 100%
rename from lib/dynasm-backend/src/emitter_x64.rs
rename to lib/singlepass-backend/src/emitter_x64.rs
diff --git a/lib/dynasm-backend/src/lib.rs b/lib/singlepass-backend/src/lib.rs
similarity index 90%
rename from lib/dynasm-backend/src/lib.rs
rename to lib/singlepass-backend/src/lib.rs
index 0092b730268..cdb275cd3c0 100644
--- a/lib/dynasm-backend/src/lib.rs
+++ b/lib/singlepass-backend/src/lib.rs
@@ -41,7 +41,7 @@ impl CacheGen for Placeholder {
         _module: &ModuleInner,
     ) -> Result<(Box<ModuleInfo>, Box<[u8]>, Memory), CacheError> {
         Err(CacheError::Unknown(
-            "the dynasm backend doesn't support caching yet".to_string(),
+            "the singlepass backend doesn't support caching yet".to_string(),
         ))
     }
 }
@@ -61,7 +61,7 @@ impl Compiler for SinglePassCompiler {
         _: Token,
     ) -> CompileResult<ModuleInner> {
         let mut mcg = codegen_x64::X64ModuleCodeGenerator::new();
-        let info = parse::read_module(wasm, Backend::Dynasm, &mut mcg, &compiler_config)?;
+        let info = parse::read_module(wasm, Backend::Singlepass, &mut mcg, &compiler_config)?;
         let (ec, resolver) = mcg.finalize(&info)?;
         Ok(ModuleInner {
             cache_gen: Box::new(Placeholder),
@@ -73,7 +73,7 @@ impl Compiler for SinglePassCompiler {
 
     unsafe fn from_cache(&self, _artifact: Artifact, _: Token) -> Result<ModuleInner, CacheError> {
         Err(CacheError::Unknown(
-            "the dynasm backend doesn't support caching yet".to_string(),
+            "the singlepass backend doesn't support caching yet".to_string(),
         ))
     }
 }
diff --git a/lib/dynasm-backend/src/machine.rs b/lib/singlepass-backend/src/machine.rs
similarity index 100%
rename from lib/dynasm-backend/src/machine.rs
rename to lib/singlepass-backend/src/machine.rs
diff --git a/lib/dynasm-backend/src/parse.rs b/lib/singlepass-backend/src/parse.rs
similarity index 100%
rename from lib/dynasm-backend/src/parse.rs
rename to lib/singlepass-backend/src/parse.rs
diff --git a/lib/dynasm-backend/src/protect_unix.rs b/lib/singlepass-backend/src/protect_unix.rs
similarity index 100%
rename from lib/dynasm-backend/src/protect_unix.rs
rename to lib/singlepass-backend/src/protect_unix.rs
diff --git a/lib/spectests/Cargo.toml b/lib/spectests/Cargo.toml
index 8dd8f83f492..d19fdab6d47 100644
--- a/lib/spectests/Cargo.toml
+++ b/lib/spectests/Cargo.toml
@@ -12,7 +12,7 @@ build = "build/mod.rs"
 wasmer-runtime-core = { path = "../runtime-core", version = "0.2.0" }
 wasmer-clif-backend = { path = "../clif-backend", version = "0.2.0" }
 wasmer-llvm-backend = { path = "../llvm-backend", version = "0.1.0", optional = true }
-wasmer-dynasm-backend = { path = "../dynasm-backend", version = "0.1.0", optional = true }
+wasmer-singlepass-backend = { path = "../singlepass-backend", version = "0.1.0", optional = true }
 
 [build-dependencies]
 wabt = "0.7.2"
@@ -25,4 +25,4 @@ default = ["fast-tests"]
 fast-tests = []
 clif = []
 llvm = ["wasmer-llvm-backend"]
-dynasm = ["wasmer-dynasm-backend"]
\ No newline at end of file
+singlepass = ["wasmer-singlepass-backend"]
diff --git a/lib/spectests/build/spectests.rs b/lib/spectests/build/spectests.rs
index a13faefd18a..10fb4567851 100644
--- a/lib/spectests/build/spectests.rs
+++ b/lib/spectests/build/spectests.rs
@@ -107,13 +107,13 @@ fn get_compiler() -> impl Compiler {
   LLVMCompiler::new()
 }
 
-#[cfg(feature = "dynasm")]
+#[cfg(feature = "singlepass")]
 fn get_compiler() -> impl Compiler {
-    use wasmer_dynasm_backend::SinglePassCompiler;
+    use wasmer_singlepass_backend::SinglePassCompiler;
     SinglePassCompiler::new()
 }
 
-#[cfg(not(any(feature = "llvm", feature = "clif", feature = "dynasm")))]
+#[cfg(not(any(feature = "llvm", feature = "clif", feature = "singlepass")))]
 fn get_compiler() -> impl Compiler {
   panic!("compiler not specified, activate a compiler via features");
   use wasmer_clif_backend::CraneliftCompiler;
diff --git a/lib/spectests/examples/simple/main.rs b/lib/spectests/examples/simple/main.rs
index c61cdb18fc7..357adb5f70d 100644
--- a/lib/spectests/examples/simple/main.rs
+++ b/lib/spectests/examples/simple/main.rs
@@ -22,13 +22,13 @@ fn get_compiler() -> impl Compiler {
     LLVMCompiler::new()
 }
 
-#[cfg(feature = "dynasm")]
+#[cfg(feature = "singlepass")]
 fn get_compiler() -> impl Compiler {
-    use wasmer_dynasm_backend::SinglePassCompiler;
+    use wasmer_singlepass_backend::SinglePassCompiler;
     SinglePassCompiler::new()
 }
 
-#[cfg(not(any(feature = "llvm", feature = "clif", feature = "dynasm")))]
+#[cfg(not(any(feature = "llvm", feature = "clif", feature = "singlepass")))]
 fn get_compiler() -> impl Compiler {
     panic!("compiler not specified, activate a compiler via features");
     use wasmer_clif_backend::CraneliftCompiler;
diff --git a/src/bin/wasmer.rs b/src/bin/wasmer.rs
index 34550355805..d8ac1cbd780 100644
--- a/src/bin/wasmer.rs
+++ b/src/bin/wasmer.rs
@@ -6,14 +6,21 @@ use std::io;
 use std::io::Read;
 use std::path::PathBuf;
 use std::process::exit;
+use std::str::FromStr;
 
 use hashbrown::HashMap;
 use structopt::StructOpt;
 
 use wasmer::webassembly::InstanceABI;
 use wasmer::*;
+use wasmer_clif_backend::CraneliftCompiler;
+use wasmer_llvm_backend::LLVMCompiler;
 use wasmer_runtime::cache::{Cache as BaseCache, FileSystemCache, WasmHash, WASMER_VERSION_HASH};
-use wasmer_runtime_core::{self, backend::CompilerConfig};
+use wasmer_runtime_core::{
+    self,
+    backend::{Compiler, CompilerConfig},
+};
+use wasmer_singlepass_backend::SinglePassCompiler;
 #[cfg(feature = "wasi")]
 use wasmer_wasi;
 
@@ -62,13 +69,51 @@ struct Run {
     #[structopt(parse(from_os_str))]
     path: PathBuf,
 
-    /// Application arguments
-    #[structopt(name = "--", raw(multiple = "true"))]
-    args: Vec<String>,
+    // Disable the cache
+    #[structopt(
+        long = "backend",
+        default_value = "cranelift",
+        raw(possible_values = "Backend::variants()", case_insensitive = "true")
+    )]
+    backend: Backend,
 
     /// Emscripten symbol map
     #[structopt(long = "em-symbol-map", parse(from_os_str))]
     em_symbol_map: Option<PathBuf>,
+
+    /// Application arguments
+    #[structopt(name = "--", raw(multiple = "true"))]
+    args: Vec<String>,
+}
+
+#[allow(dead_code)]
+#[derive(Debug)]
+enum Backend {
+    Cranelift,
+    Singlepass,
+    LLVM,
+}
+
+impl Backend {
+    pub fn variants() -> &'static [&'static str] {
+        &["singlepass", "cranelift", "llvm"]
+    }
+}
+
+impl FromStr for Backend {
+    type Err = String;
+    fn from_str(s: &str) -> Result<Backend, String> {
+        match s.to_lowercase().as_str() {
+            "singlepass" => Ok(Backend::Singlepass),
+            "cranelift" => Ok(Backend::Cranelift),
+            "llvm" => Ok(Backend::LLVM),
+            // "llvm" => Err(
+            //     "The LLVM backend option is not enabled by default due to binary size constraints"
+            //         .to_string(),
+            // ),
+            _ => Err(format!("The backend {} doesn't exist", s)),
+        }
+    }
 }
 
 #[derive(Debug, StructOpt)]
@@ -177,6 +222,12 @@ fn execute_wasm(options: &Run) -> Result<(), String> {
             .map_err(|e| format!("Can't convert from wast to wasm: {:?}", e))?;
     }
 
+    let compiler: Box<dyn Compiler> = match options.backend {
+        Backend::Singlepass => Box::new(SinglePassCompiler::new()),
+        Backend::Cranelift => Box::new(CraneliftCompiler::new()),
+        Backend::LLVM => Box::new(LLVMCompiler::new()),
+    };
+
     let module = if !disable_cache {
         // If we have cache enabled
 
@@ -202,11 +253,12 @@ fn execute_wasm(options: &Run) -> Result<(), String> {
                 module
             }
             Err(_) => {
-                let module = webassembly::compile_with_config(
+                let module = webassembly::compile_with_config_with(
                     &wasm_binary[..],
                     CompilerConfig {
                         symbol_map: em_symbol_map,
                     },
+                    &*compiler,
                 )
                 .map_err(|e| format!("Can't compile module: {:?}", e))?;
                 // We try to save the module into a cache file
@@ -217,11 +269,12 @@ fn execute_wasm(options: &Run) -> Result<(), String> {
         };
         module
     } else {
-        webassembly::compile_with_config(
+        webassembly::compile_with_config_with(
             &wasm_binary[..],
             CompilerConfig {
                 symbol_map: em_symbol_map,
             },
+            &*compiler,
         )
         .map_err(|e| format!("Can't compile module: {:?}", e))?
     };
diff --git a/src/webassembly.rs b/src/webassembly.rs
index 01367795aed..fc32b3299a0 100644
--- a/src/webassembly.rs
+++ b/src/webassembly.rs
@@ -1,4 +1,5 @@
 use std::panic;
+pub use wasmer_runtime::compile_with_config_with;
 use wasmer_runtime::{
     self as runtime,
     error::{CallResult, Result},
@@ -78,15 +79,15 @@ pub fn compile(buffer_source: &[u8]) -> Result<Module> {
     Ok(module)
 }
 
-/// The same as `compile` but takes a `CompilerConfig` for the purpose of
-/// changing the compiler's behavior
-pub fn compile_with_config(
-    buffer_source: &[u8],
-    compiler_config: CompilerConfig,
-) -> Result<Module> {
-    let module = runtime::compile_with_config(buffer_source, compiler_config)?;
-    Ok(module)
-}
+// /// The same as `compile` but takes a `CompilerConfig` for the purpose of
+// /// changing the compiler's behavior
+// pub fn compile_with_config_with(
+//     buffer_source: &[u8],
+//     compiler_config: CompilerConfig,
+// ) -> Result<Module> {
+//     let module = runtime::compile_with_config(buffer_source, compiler_config)?;
+//     Ok(module)
+// }
 
 /// Performs common instance operations needed when an instance is first run
 /// including data setup, handling arguments and calling a main function