diff --git a/Cargo.lock b/Cargo.lock
index 23bf416a..519297bf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -80,22 +80,23 @@ dependencies = [
 
 [[package]]
 name = "bindgen"
-version = "0.46.0"
+version = "0.51.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cexpr 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "clang-sys 0.26.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "clang-sys 0.28.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "hashbrown 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fxhash 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "peeking_take_while 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "shlex 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "which 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -106,12 +107,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "blake2b_simd"
-version = "0.4.1"
+version = "0.5.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "arrayref 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "arrayvec 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "constant_time_eq 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -131,19 +131,18 @@ dependencies = [
 
 [[package]]
 name = "cbindgen"
-version = "0.8.7"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_derive 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "toml 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "toml 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -176,10 +175,10 @@ dependencies = [
 
 [[package]]
 name = "clang-sys"
-version = "0.26.4"
+version = "0.28.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "glob 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
  "libloading 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -320,6 +319,30 @@ dependencies = [
  "generic-array 0.12.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "dynasm"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "owning_ref 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "dynasmrt"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memmap 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "take_mut 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "either"
 version = "1.5.2"
@@ -381,6 +404,14 @@ name = "fuchsia-cprng"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "fxhash"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "gcc"
 version = "0.3.55"
@@ -406,24 +437,14 @@ dependencies = [
 
 [[package]]
 name = "glob"
-version = "0.2.11"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "go-ext-wasm"
 version = "0.2.0"
 dependencies = [
- "wasmer-runtime-c-api 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "hashbrown"
-version = "0.1.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wasmer-runtime-c-api 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
 ]
 
 [[package]]
@@ -443,6 +464,9 @@ dependencies = [
 name = "indexmap"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "itoa"
@@ -479,11 +503,10 @@ dependencies = [
 
 [[package]]
 name = "lock_api"
-version = "0.1.5"
+version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "owning_ref 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "scopeguard 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -499,6 +522,15 @@ name = "memchr"
 version = "2.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "memmap"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "memmap"
 version = "0.7.0"
@@ -518,7 +550,7 @@ dependencies = [
 
 [[package]]
 name = "nix"
-version = "0.14.1"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -568,7 +600,7 @@ dependencies = [
 
 [[package]]
 name = "owning_ref"
-version = "0.4.0"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "stable_deref_trait 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -586,20 +618,23 @@ dependencies = [
 
 [[package]]
 name = "parking_lot"
-version = "0.7.1"
+version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "lock_api 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "parking_lot_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lock_api 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parking_lot_core 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "parking_lot_core"
-version = "0.4.0"
+version = "0.6.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
+ "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -664,24 +699,6 @@ dependencies = [
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "rand"
-version = "0.6.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "autocfg 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_jitter 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_os 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_pcg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "rand"
 version = "0.7.0"
@@ -694,15 +711,6 @@ dependencies = [
  "rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "rand_chacha"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "autocfg 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "rand_chacha"
 version = "0.2.1"
@@ -733,14 +741,6 @@ dependencies = [
  "getrandom 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "rand_hc"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "rand_hc"
 version = "0.2.0"
@@ -749,54 +749,6 @@ dependencies = [
  "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "rand_isaac"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_jitter"
-version = "0.1.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_os"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_pcg"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "autocfg 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_xorshift"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "raw-cpuid"
 version = "6.1.0"
@@ -889,11 +841,6 @@ name = "ryu"
 version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "scopeguard"
-version = "0.3.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "scopeguard"
 version = "1.0.0"
@@ -931,7 +878,7 @@ dependencies = [
 
 [[package]]
 name = "serde_bytes"
-version = "0.10.5"
+version = "0.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -957,6 +904,11 @@ dependencies = [
  "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "shlex"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "smallvec"
 version = "0.6.10"
@@ -1003,6 +955,11 @@ dependencies = [
  "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "take_mut"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "target-lexicon"
 version = "0.4.0"
@@ -1052,7 +1009,7 @@ dependencies = [
 
 [[package]]
 name = "toml"
-version = "0.4.10"
+version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1101,25 +1058,24 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "wasmer-clif-backend"
 version = "0.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+source = "git+https://github.com/confio/wasmer?branch=metering#64a9353e32af34be01da2f650176191677e5f4f7"
 dependencies = [
  "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "cranelift-codegen 0.31.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cranelift-entity 0.31.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cranelift-native 0.31.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "hashbrown 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
- "nix 0.14.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "nix 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde-bench 0.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_bytes 0.10.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_bytes 0.11.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)",
  "target-lexicon 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasmer-clif-fork-frontend 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasmer-clif-fork-wasm 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "wasmer-runtime-core 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "wasmer-win-exception-handler 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wasmer-runtime-core 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
+ "wasmer-win-exception-handler 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
  "wasmparser 0.35.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1148,67 +1104,94 @@ dependencies = [
  "wasmparser 0.35.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "wasmer-middleware-common"
+version = "0.6.0"
+source = "git+https://github.com/confio/wasmer?branch=metering#64a9353e32af34be01da2f650176191677e5f4f7"
+dependencies = [
+ "wasmer-runtime-core 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
+]
+
 [[package]]
 name = "wasmer-runtime"
 version = "0.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+source = "git+https://github.com/confio/wasmer?branch=metering#64a9353e32af34be01da2f650176191677e5f4f7"
 dependencies = [
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "memmap 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "wasmer-clif-backend 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "wasmer-runtime-core 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wasmer-clif-backend 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
+ "wasmer-runtime-core 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
+ "wasmer-singlepass-backend 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
 ]
 
 [[package]]
 name = "wasmer-runtime-c-api"
 version = "0.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+source = "git+https://github.com/confio/wasmer?branch=metering#64a9353e32af34be01da2f650176191677e5f4f7"
 dependencies = [
- "cbindgen 0.8.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cbindgen 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
- "wasmer-runtime 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "wasmer-runtime-core 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wasmer-middleware-common 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
+ "wasmer-runtime 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
+ "wasmer-runtime-core 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
+ "wasmer-singlepass-backend 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)",
 ]
 
 [[package]]
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-"checksum rand_os 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "7b75f676a1e053fc562eafbb47838d67c84801e38fc1ba459e8f180deabd5071"
-"checksum rand_pcg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "abf9b09b01790cfe0364f52bf32995ea3c39f4d2dd011eac241d2914146d0b44"
-"checksum rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cbf7e9e623549b0e21f6e97cf8ecf247c1a8fd2e8a992ae265314300b2455d5c"
 "checksum raw-cpuid 6.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "30a9d219c32c9132f7be513c18be77c9881c7107d2ab5569d205a6a0f0e6dc7d"
 "checksum rayon 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a4b0186e22767d5b9738a05eab7c6ac90b15db17e5b5f9bd87976dd7d89a10a4"
 "checksum rayon-core 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ebbe0df8435ac0c397d467b6cad6d25543d06e8a019ef3f6af3c384597515bd2"
@@ -1389,27 +1367,28 @@ dependencies = [
 "checksum rustc-demangle 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "4c691c0e608126e00913e33f0ccf3727d5fc84573623b8d65b2df340b5201783"
 "checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
 "checksum ryu 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c92464b447c0ee8c4fb3824ecc8383b81717b9f1e74ba2e72540aef7b9f82997"
-"checksum scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "94258f53601af11e6a49f722422f6e3425c52b06245a5cf9bc09908b174f5e27"
 "checksum scopeguard 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b42e15e59b18a828bbf5c58ea01debb36b9b096346de35d941dcb89009f24a0d"
 "checksum semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
 "checksum semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 "checksum serde 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)" = "fec2851eb56d010dc9a21b89ca53ee75e6528bab60c11e89d38390904982da9f"
 "checksum serde-bench 0.0.7 (registry+https://github.com/rust-lang/crates.io-index)" = "d733da87e79faaac25616e33d26299a41143fd4cd42746cbb0e91d8feea243fd"
-"checksum serde_bytes 0.10.5 (registry+https://github.com/rust-lang/crates.io-index)" = "defbb8a83d7f34cc8380751eeb892b825944222888aff18996ea7901f24aec88"
+"checksum serde_bytes 0.11.2 (registry+https://github.com/rust-lang/crates.io-index)" = "45af0182ff64abaeea290235eb67da3825a576c5d53e642c4d5b652e12e6effc"
 "checksum serde_derive 1.0.99 (registry+https://github.com/rust-lang/crates.io-index)" = "cb4dc18c61206b08dc98216c98faa0232f4337e1e1b8574551d5bad29ea1b425"
 "checksum serde_json 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)" = "051c49229f282f7c6f3813f8286cc1e3323e8051823fce42c7ea80fe13521704"
+"checksum shlex 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7fdf1b9db47230893d76faad238fd6097fd6d6a9245cd7a4d90dbd639536bbd2"
 "checksum smallvec 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)" = "ab606a9c5e214920bb66c458cd7be8ef094f813f20fe77a54cc7dbfff220d4b7"
 "checksum stable_deref_trait 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dba1a27d3efae4351c8051072d619e3ade2820635c3958d826bfea39d59b54c8"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 "checksum syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)" = "9ca4b3b69a77cbe1ffc9e198781b7acb0c7365a883670e8f1c1bc66fba79a5c5"
 "checksum syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "66850e97125af79138385e9b88339cbcd037e3f28ceab8c5ad98e64f0f1f80bf"
 "checksum synstructure 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)" = "02353edf96d6e4dc81aea2d8490a7e9db177bf8acb0e951c24940bf866cb313f"
+"checksum take_mut 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f764005d11ee5f36500a149ace24e00e3da98b0158b3e2d53a7495660d3f4d60"
 "checksum target-lexicon 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1b0ab4982b8945c35cc1c46a83a9094c414f6828a099ce5dcaa8ee2b04642dcb"
 "checksum tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e24d9338a0a5be79593e2fa15a648add6138caa803e2d5bc782c371732ca9"
 "checksum termcolor 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "96d6098003bde162e4277c70665bd87c326f5a0c3f3fbfb285787fa482d54e6e"
 "checksum textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
 "checksum thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c6b53e329000edc2b34dbe8545fd20e55a333362d0a321909685a19bd28c3f1b"
-"checksum toml 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)" = "758664fc71a3a69038656bee8b6be6477d2a6c315a6b81f7081f591bffa4111f"
+"checksum toml 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "c7aabe75941d914b72bf3e5d3932ed92ce0664d49d8432305a8b547c37227724"
 "checksum typenum 1.11.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6d2783fe2d6b8c1101136184eb41be8b1ad379e4657050b8aaff0c79ee7575f9"
 "checksum unicode-width 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "7007dbd421b92cc6e28410fe7362e2e0a2503394908f417b68ec8d1c364c4e20"
 "checksum unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fc72304796d0818e357ead4e000d19c9c174ab23dc11093ac919054d20a6a7fc"
@@ -1418,13 +1397,15 @@ dependencies = [
 "checksum version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "914b1a6776c4c929a602fafd8bc742e06365d4bcbe48c30f9cca5824f70dc9dd"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
 "checksum wasi 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fd5442abcac6525a045cc8c795aedb60da7a2e5e89c7bf18a0d5357849bb23c7"
-"checksum wasmer-clif-backend 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3d1042c2e62e5a923aa0f3d1408aab75727bc331b880871c0962374b21948e15"
+"checksum wasmer-clif-backend 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)" = "<none>"
 "checksum wasmer-clif-fork-frontend 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3bd6bec1587a3b11222f4ff129fd119785713c41de413f54f99d3c03743812f4"
 "checksum wasmer-clif-fork-wasm 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a8f323e612fe2549391255a09f89c927d7feb0ec4bf0c2cad9e3c089bdca42fc"
-"checksum wasmer-runtime 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1db836a723c89fd935f7e36b48fd7658e100c111268e9b049167cd7b048604fe"
-"checksum wasmer-runtime-c-api 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "97ff7c84ce1a9a51e3f83f4a24390cae5555781d9469160381d31056c497e303"
-"checksum wasmer-runtime-core 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a12307202a44e391df4b3fd532e7fb02db0b927579d2d65d876a9dcc37042a51"
-"checksum wasmer-win-exception-handler 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "989cf6e7c3c306efea25bc10d293708bdc53d49627120be82c3533d2f2844b8f"
+"checksum wasmer-middleware-common 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)" = "<none>"
+"checksum wasmer-runtime 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)" = "<none>"
+"checksum wasmer-runtime-c-api 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)" = "<none>"
+"checksum wasmer-runtime-core 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)" = "<none>"
+"checksum wasmer-singlepass-backend 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)" = "<none>"
+"checksum wasmer-win-exception-handler 0.6.0 (git+https://github.com/confio/wasmer?branch=metering)" = "<none>"
 "checksum wasmparser 0.35.3 (registry+https://github.com/rust-lang/crates.io-index)" = "099aaf77635ffad3d9ab57253c29b16a46e93755c3e54cfe33fb8cf4b54f760b"
 "checksum which 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b57acb10231b9493c8472b20cb57317d0679a49e0bdbee44b3b803a6473af164"
 "checksum winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
diff --git a/Cargo.toml b/Cargo.toml
index ddbca32d..919a8d6c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,4 +14,4 @@ categories = ["wasm"]
 crate-type = ["cdylib"]
 
 [dependencies]
-wasmer-runtime-c-api = "0.6.0"
\ No newline at end of file
+wasmer-runtime-c-api =  { git = "https://github.com/confio/wasmer", branch = "metering", features = ["metering"] }
diff --git a/justfile b/justfile
index a9ad9d64..b11feab0 100644
--- a/justfile
+++ b/justfile
@@ -27,6 +27,12 @@ build-bin go-build-args='-v':
 rust:
 	cargo build --release
 
+rust-install:
+	cargo build --release
+	# grabs the most recent *.so file - TODO: only works on linux
+	ls -ltR target/release/deps/libwasmer_runtime_c_api-*.so | head -1
+	cp $(ls -tR target/release/deps/libwasmer_runtime_c_api-*.so | head -1) wasmer/libwasmer_runtime_c_api.so
+
 # Generate cgo debug objects.
 debug-cgo:
 	cd wasmer/ && \
@@ -41,9 +47,9 @@ test:
 	# Run the tests.
 	GODEBUG=cgocheck=2 go test -test.v $(find test -type f \( -name "*_test.go" \! -name "example_*.go" \! -name "benchmark*.go" \) ) test/imports.go
 	# Run the short examples.
-	go test -test.v example_test.go
+	go test -count=1 -test.v example_test.go
 	# Run the long examples.
-	go test -test.v $(find . -type f \( -name "example_*_test.go" \! -name "_example_import_test.go" \) )
+	go test -count=1 -test.v $(find . -type f \( -name "example_*_test.go" \! -name "_example_import_test.go" \) )
 
 # Run benchmarks. Subjects can be `wasmer`, `wagon` or `life`. Filter is a regex to select the benchmarks.
 bench subject='wasmer' filter='.*':
diff --git a/wasmer/bridge.go b/wasmer/bridge.go
index ce708528..44c5e60a 100644
--- a/wasmer/bridge.go
+++ b/wasmer/bridge.go
@@ -64,6 +64,31 @@ func cWasmerCompile(module **cWasmerModuleT, wasmBytes *cUchar, wasmBytesLength
 	))
 }
 
+
+// TODO: is this an auto-gen file? how should I create this?
+func cWasmerCompileWithLimit(module **cWasmerModuleT, wasmBytes *cUchar, wasmBytesLength cUint, gasLimit uint64) cWasmerResultT {
+	return (cWasmerResultT)(C.wasmer_compile_with_limit(
+		(**C.wasmer_module_t)(unsafe.Pointer(module)),
+		(*C.uchar)(wasmBytes),
+		(C.uint)(wasmBytesLength),
+		(C.uint64_t)(gasLimit),
+	))
+}
+
+func cWasmerInstanceGetPointsUsed(instance *cWasmerInstanceT) uint64 {
+	return uint64(C.wasmer_instance_get_points_used(
+		(*C.wasmer_instance_t)(instance),
+	))
+}
+
+func cWasmerInstanceSetPointsUsed(instance *cWasmerInstanceT, points uint64) {
+	C.wasmer_instance_set_points_used(
+		(*C.wasmer_instance_t)(instance),
+		(C.uint64_t)(points),
+	)
+}
+// End TODO: autogen?
+
 func cWasmerExportDescriptorKind(exportDescriptor *cWasmerExportDescriptorT) cWasmerImportExportKind {
 	return (cWasmerImportExportKind)(C.wasmer_export_descriptor_kind(
 		(*C.wasmer_export_descriptor_t)(exportDescriptor),
diff --git a/wasmer/example_test.go b/wasmer/example_test.go
index 3b3db1bb..a9255519 100644
--- a/wasmer/example_test.go
+++ b/wasmer/example_test.go
@@ -2,9 +2,10 @@ package wasmer_test
 
 import (
 	"fmt"
-	wasm "github.com/wasmerio/go-ext-wasm/wasmer"
 	"path"
 	"runtime"
+
+	wasm "github.com/wasmerio/go-ext-wasm/wasmer"
 )
 
 func GetBytes() []byte {
diff --git a/wasmer/instance.go b/wasmer/instance.go
index 0a055cda..c001dfe2 100644
--- a/wasmer/instance.go
+++ b/wasmer/instance.go
@@ -439,3 +439,11 @@ func (instance *Instance) Close() {
 		cWasmerInstanceDestroy(instance.instance)
 	}
 }
+
+func (instance *Instance) GetPointsUsed() uint64 {
+	return cWasmerInstanceGetPointsUsed(instance.instance)
+}
+
+func (instance *Instance) SetPointsUsed(points uint64) {
+	cWasmerInstanceSetPointsUsed(instance.instance, points)
+}
diff --git a/wasmer/libwasmer_runtime_c_api.so b/wasmer/libwasmer_runtime_c_api.so
old mode 100644
new mode 100755
index e6e81ca8..89bbecf6
Binary files a/wasmer/libwasmer_runtime_c_api.so and b/wasmer/libwasmer_runtime_c_api.so differ
diff --git a/wasmer/module.go b/wasmer/module.go
index 6dfaaaca..ebd5ec8e 100644
--- a/wasmer/module.go
+++ b/wasmer/module.go
@@ -106,6 +106,29 @@ func Compile(bytes []byte) (Module, error) {
 	return Module{module, exports, imports}, nil
 }
 
+// Compile compiles a WebAssembly module from bytes, with a fixed gas limit
+func CompileWithLimit(bytes []byte, gasLimit uint64) (Module, error) {
+	var module *cWasmerModuleT
+
+	var compileResult = cWasmerCompileWithLimit(
+		&module,
+		(*cUchar)(unsafe.Pointer(&bytes[0])),
+		cUint(len(bytes)),
+		gasLimit,
+	)
+
+	var emptyModule = Module{module: nil}
+
+	if compileResult != cWasmerOk {
+		return emptyModule, NewModuleError("Failed to compile the module.")
+	}
+
+	var exports = moduleExports(module)
+	var imports = moduleImports(module)
+
+	return Module{module, exports, imports}, nil
+}
+
 func moduleExports(module *cWasmerModuleT) []ExportDescriptor {
 	var exportDescriptors *cWasmerExportDescriptorsT
 	cWasmerExportDescriptors(module, &exportDescriptors)
diff --git a/wasmer/test/module_test.go b/wasmer/test/module_test.go
index a206cf00..fea56874 100644
--- a/wasmer/test/module_test.go
+++ b/wasmer/test/module_test.go
@@ -1,11 +1,12 @@
 package wasmertest
 
 import (
-	"github.com/stretchr/testify/assert"
-	wasm "github.com/wasmerio/go-ext-wasm/wasmer"
 	"path"
 	"runtime"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
+	wasm "github.com/wasmerio/go-ext-wasm/wasmer"
 )
 
 func TestValidate(t *testing.T) {
@@ -58,6 +59,74 @@ func TestModuleInstantiate(t *testing.T) {
 	assert.Equal(t, wasm.I32(3), result)
 }
 
+func TestModuleInstantiateWithLimit(t *testing.T) {
+	module, err := wasm.CompileWithLimit(GetBytes(), 20000)
+	defer module.Close()
+
+	assert.NoError(t, err)
+
+	instance, err := module.Instantiate()
+	defer instance.Close()
+
+	assert.NoError(t, err)
+
+	result, _ := instance.Exports["sum"](1, 2)
+
+	assert.Equal(t, wasm.I32(3), result)
+}
+
+// TODO: this only passes if the metering feature flag is enabled in the rust binary
+func TestModuleRunWithLimit(t *testing.T) {
+	module, err := wasm.CompileWithLimit(GetBytes(), 20000)
+	defer module.Close()
+	assert.NoError(t, err)
+
+	instance, err := module.Instantiate()
+	defer instance.Close()
+	assert.NoError(t, err)
+
+	// we start at 0
+	points := instance.GetPointsUsed()
+	assert.Equal(t, points, uint64(0))
+
+	// if we set it, it is updated in get
+	instance.SetPointsUsed(123)
+	points = instance.GetPointsUsed()
+	assert.Equal(t, points, uint64(123))
+
+	result, _ := instance.Exports["sum"](1, 2)
+	assert.Equal(t, wasm.I32(3), result)
+
+	// running the contract adds 4 points
+	points = instance.GetPointsUsed()
+	assert.Equal(t, points, uint64(127))
+}
+
+// TODO: this only passes if the metering feature flag is enabled in the rust binary
+func TestModuleRunExceedsLimit(t *testing.T) {
+	module, err := wasm.CompileWithLimit(GetBytes(), 5)
+	defer module.Close()
+	assert.NoError(t, err)
+
+	instance, err := module.Instantiate()
+	defer instance.Close()
+	assert.NoError(t, err)
+
+	// we start at 0
+	points := instance.GetPointsUsed()
+	assert.Equal(t, points, uint64(0))
+	// but let's hit the limit
+	instance.SetPointsUsed(1001)
+
+	// this should be out-of-gas
+	_, err = instance.Exports["sum"](1, 2)
+	assert.Error(t, err)
+
+	// and 4 points are added anyway :(
+	points = instance.GetPointsUsed()
+	assert.Equal(t, points, uint64(1005))
+}
+
 func TestModuleSerialize(t *testing.T) {
 	module1, err := wasm.Compile(GetBytes())
 	defer module1.Close()
diff --git a/wasmer/wasmer.h b/wasmer/wasmer.h
index 7c0f5249..ad973156 100644
--- a/wasmer/wasmer.h
+++ b/wasmer/wasmer.h
@@ -6,6 +6,9 @@
 #include <stdint.h>
 #include <stdlib.h>
 
+/**
+ * List of export/import kinds.
+ */
 enum wasmer_import_export_kind {
   WASM_FUNCTION,
   WASM_GLOBAL,
@@ -31,6 +34,9 @@ typedef struct {
 
 } wasmer_module_t;
 
+/**
+ * Opaque pointer to `NamedExportDescriptor`.
+ */
 typedef struct {
 
 } wasmer_export_descriptor_t;
@@ -40,10 +46,16 @@ typedef struct {
   uint32_t bytes_len;
 } wasmer_byte_array;
 
+/**
+ * Opaque pointer to `NamedExportDescriptors`.
+ */
 typedef struct {
 
 } wasmer_export_descriptors_t;
 
+/**
+ * Opaque pointer to `wasmer_export_t`.
+ */
 typedef struct {
 
 } wasmer_export_func_t;
@@ -60,6 +72,9 @@ typedef struct {
   wasmer_value value;
 } wasmer_value_t;
 
+/**
+ * Opaque pointer to `NamedExport`.
+ */
 typedef struct {
 
 } wasmer_export_t;
@@ -68,6 +83,9 @@ typedef struct {
 
 } wasmer_memory_t;
 
+/**
+ * Opaque pointer to `NamedExports`.
+ */
 typedef struct {
 
 } wasmer_exports_t;
@@ -95,16 +113,15 @@ typedef struct {
 
 typedef struct {
 
-} wasmer_instance_t;
-
-typedef struct {
-
-} wasmer_instance_context_t;
+} wasmer_import_object_t;
 
 typedef struct {
 
 } wasmer_table_t;
 
+/**
+ * Union of import/export value.
+ */
 typedef union {
   const wasmer_import_func_t *func;
   const wasmer_table_t *table;
@@ -119,6 +136,14 @@ typedef struct {
   wasmer_import_export_value value;
 } wasmer_import_t;
 
+typedef struct {
+
+} wasmer_instance_t;
+
+typedef struct {
+
+} wasmer_instance_context_t;
+
 typedef struct {
   bool has_some;
   uint32_t some;
@@ -155,6 +180,17 @@ wasmer_result_t wasmer_compile(wasmer_module_t **module,
                                uint8_t *wasm_bytes,
                                uint32_t wasm_bytes_len);
 
+/**
+ * Creates a new Module with gas limit from the given wasm bytes.
+ * Returns `wasmer_result_t::WASMER_OK` upon success.
+ * Returns `wasmer_result_t::WASMER_ERROR` upon failure. Use `wasmer_last_error_length`
+ * and `wasmer_last_error_message` to get an error message.
+ */
+wasmer_result_t wasmer_compile_with_limit(wasmer_module_t **module,
+                                          uint8_t *wasm_bytes,
+                                          uint32_t wasm_bytes_len,
+                                          uint64_t gas_limit);
+
 /**
  * Gets export descriptor kind
  */
@@ -392,6 +428,24 @@ wasmer_result_t wasmer_import_func_returns(const wasmer_import_func_t *func,
 wasmer_result_t wasmer_import_func_returns_arity(const wasmer_import_func_t *func,
                                                  uint32_t *result);
 
+/**
+ * Frees memory of the given ImportObject
+ */
+void wasmer_import_object_destroy(wasmer_import_object_t *import_object);
+
+/**
+ * Extends an existing import object with new imports
+ */
+wasmer_result_t wasmer_import_object_extend(wasmer_import_object_t *import_object,
+                                            wasmer_import_t *imports,
+                                            unsigned int imports_len);
+
+/**
+ * Creates a new empty import object.
+ * See also `wasmer_import_object_append`
+ */
+wasmer_import_object_t *wasmer_import_object_new(void);
+
 /**
  * Calls an instances exported function by `name` with the provided parameters.
  * Results are set using the provided `results` pointer.
@@ -417,6 +471,11 @@ void *wasmer_instance_context_data_get(const wasmer_instance_context_t *ctx);
  */
 void wasmer_instance_context_data_set(wasmer_instance_t *instance, void *data_ptr);
 
+/**
+ * Extracts the instance's context and returns it.
+ */
+const wasmer_instance_context_t *wasmer_instance_context_get(wasmer_instance_t *instance);
+
 /**
  * Gets the memory within the context at the index `memory_idx`.
  * The index is always 0 until multiple memories are supported.
@@ -435,6 +494,10 @@ void wasmer_instance_destroy(wasmer_instance_t *instance);
  */
 void wasmer_instance_exports(wasmer_instance_t *instance, wasmer_exports_t **exports);
 
+uint64_t wasmer_instance_get_points_used(wasmer_instance_t *instance);
+
+void wasmer_instance_set_points_used(wasmer_instance_t *instance, uint64_t new_gas);
+
 /**
  * Creates a new Instance from the given wasm bytes and imports.
  * Returns `wasmer_result_t::WASMER_OK` upon success.
@@ -526,6 +589,16 @@ wasmer_result_t wasmer_module_deserialize(wasmer_module_t **module,
  */
 void wasmer_module_destroy(wasmer_module_t *module);
 
+/**
+ * Given:
+ *  A prepared `wasmer` import-object
+ *  A compiled wasmer module
+ * Instantiates a wasmer instance
+ */
+wasmer_result_t wasmer_module_import_instantiate(wasmer_instance_t **instance,
+                                                 const wasmer_module_t *module,
+                                                 const wasmer_import_object_t *import_object);
+
 /**
  * Creates a new Instance from the given module and imports.
  * Returns `wasmer_result_t::WASMER_OK` upon success.