diff --git a/Cargo.lock b/Cargo.lock
index 80063eae02b6..b586db99c227 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -64,6 +64,15 @@ dependencies = [
  "const-random",
 ]
 
+[[package]]
+name = "ahash"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0989268a37e128d4d7a8028f1c60099430113fdbc70419010601ce51a228e4fe"
+dependencies = [
+ "const-random",
+]
+
 [[package]]
 name = "aho-corasick"
 version = "0.7.8"
@@ -73,6 +82,15 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "ansi_term"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
+dependencies = [
+ "winapi 0.3.8",
+]
+
 [[package]]
 name = "anyhow"
 version = "1.0.26"
@@ -100,6 +118,64 @@ version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cff77d8686867eceff3105329d4698d96c2391c176d5d03adc90c7389162b5b8"
 
+[[package]]
+name = "async-std"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "538ecb01eb64eecd772087e5b6f7540cbc917f047727339a472dafed2185b267"
+dependencies = [
+ "async-task",
+ "crossbeam-channel",
+ "crossbeam-deque",
+ "crossbeam-utils",
+ "futures-core",
+ "futures-io",
+ "futures-timer 2.0.2",
+ "kv-log-macro",
+ "log",
+ "memchr",
+ "mio",
+ "mio-uds",
+ "num_cpus",
+ "once_cell 1.3.1",
+ "pin-project-lite",
+ "pin-utils",
+ "slab",
+]
+
+[[package]]
+name = "async-task"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ac2c016b079e771204030951c366db398864f5026f84a44dafb0ff20f02085d"
+dependencies = [
+ "libc",
+ "winapi 0.3.8",
+]
+
+[[package]]
+name = "async-tls"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ce6977f57fa68da77ffe5542950d47e9c23d65f5bc7cb0a9f8700996913eec7"
+dependencies = [
+ "futures",
+ "rustls",
+ "webpki",
+ "webpki-roots",
+]
+
+[[package]]
+name = "atty"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
+dependencies = [
+ "hermit-abi",
+ "libc",
+ "winapi 0.3.8",
+]
+
 [[package]]
 name = "autocfg"
 version = "0.1.7"
@@ -150,6 +226,21 @@ dependencies = [
  "safemem",
 ]
 
+[[package]]
+name = "base64"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b25d992356d2eb0ed82172f5248873db5560c4721f564b13cb5193bda5e668e"
+dependencies = [
+ "byteorder",
+]
+
+[[package]]
+name = "base64"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b41b7ea54a0c9d92199de89e20e58d49f02f8e699814ef3fdf266f6f748d15c7"
+
 [[package]]
 name = "bitflags"
 version = "1.2.1"
@@ -218,6 +309,21 @@ dependencies = [
  "byte-tools",
 ]
 
+[[package]]
+name = "bs58"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b170cd256a3f9fa6b9edae3e44a7dfdfc77e8124dbc3e2612d75f9c3e2396dae"
+
+[[package]]
+name = "bstr"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "502ae1441a0a5adb8fbd38a5955a6416b9493e92b465de5e4a9bde6a539c2c48"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "bumpalo"
 version = "3.2.0"
@@ -242,6 +348,12 @@ version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
 
+[[package]]
+name = "bytes"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "130aac562c0dd69c56b3b1cc8ffd2e17be31d0b6c25b61c96b76231aa23e39e1"
+
 [[package]]
 name = "c2-chacha"
 version = "0.2.3"
@@ -263,6 +375,21 @@ version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
 
+[[package]]
+name = "clap"
+version = "2.33.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5067f5bb2d80ef5d68b4c87db81601f0b75bca627bc2ef76b141d7b846a3c6d9"
+dependencies = [
+ "ansi_term",
+ "atty",
+ "bitflags",
+ "strsim",
+ "textwrap",
+ "unicode-width",
+ "vec_map",
+]
+
 [[package]]
 name = "clear_on_drop"
 version = "0.2.3"
@@ -307,6 +434,50 @@ version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "245097e9a4535ee1e3e3931fcfcd55a796a44c643e8596ff6566d68f09b87bbc"
 
+[[package]]
+name = "crossbeam-channel"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "acec9a3b0b3559f15aee4f90746c4e5e293b701c0f7d3925d24e01645267b68c"
+dependencies = [
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-deque"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3aa945d63861bfe624b55d153a39684da1e8c0bc8fba932f7ee3a3c16cea3ca"
+dependencies = [
+ "crossbeam-epoch",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5064ebdbf05ce3cb95e45c8b086f72263f4166b29b97f6baff7ef7fe047b55ac"
+dependencies = [
+ "autocfg 0.1.7",
+ "cfg-if",
+ "crossbeam-utils",
+ "lazy_static",
+ "memoffset",
+ "scopeguard 1.0.0",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ce446db02cdc3165b94ae73111e570793400d0794e46125cc4056c81cbb039f4"
+dependencies = [
+ "autocfg 0.1.7",
+ "cfg-if",
+ "lazy_static",
+]
+
 [[package]]
 name = "crunchy"
 version = "0.2.2"
@@ -333,6 +504,16 @@ dependencies = [
  "stream-cipher",
 ]
 
+[[package]]
+name = "ctrlc"
+version = "3.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7dfd2d8b4c82121dfdff120f818e09fc4380b0b7e17a742081a89b94853e87f"
+dependencies = [
+ "nix",
+ "winapi 0.3.8",
+]
+
 [[package]]
 name = "curve25519-dalek"
 version = "1.2.3"
@@ -391,6 +572,19 @@ dependencies = [
  "sha2",
 ]
 
+[[package]]
+name = "env_logger"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44533bbbb3bb3c1fa17d9f2e4e38bbbaf8396ba82193c4cb1b6445d711445d36"
+dependencies = [
+ "atty",
+ "humantime",
+ "log",
+ "regex",
+ "termcolor",
+]
+
 [[package]]
 name = "environmental"
 version = "1.1.1"
@@ -465,10 +659,16 @@ dependencies = [
  "static_assertions",
 ]
 
+[[package]]
+name = "fnv"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2fad85553e09a6f881f739c29f0b00b0f01357c743266d478b68951ce23285f3"
+
 [[package]]
 name = "frame-metadata"
 version = "11.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "parity-scale-codec",
  "serde",
@@ -479,7 +679,7 @@ dependencies = [
 [[package]]
 name = "frame-support"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "bitmask",
  "frame-metadata",
@@ -503,7 +703,7 @@ dependencies = [
 [[package]]
 name = "frame-support-procedural"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "frame-support-procedural-tools",
  "proc-macro2 1.0.8",
@@ -514,7 +714,7 @@ dependencies = [
 [[package]]
 name = "frame-support-procedural-tools"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "frame-support-procedural-tools-derive",
  "proc-macro-crate",
@@ -526,7 +726,7 @@ dependencies = [
 [[package]]
 name = "frame-support-procedural-tools-derive"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "proc-macro2 1.0.8",
  "quote 1.0.2",
@@ -536,7 +736,7 @@ dependencies = [
 [[package]]
 name = "frame-system"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "frame-support",
  "impl-trait-for-tuples",
@@ -555,6 +755,22 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a06f77d526c1a601b7c4cdd98f54b5eaabffc14d5f2f0296febdc7f357c6d3ba"
 
+[[package]]
+name = "fuchsia-zircon"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2e9763c69ebaae630ba35f74888db465e49e259ba1bc0eda7d06f4a067615d82"
+dependencies = [
+ "bitflags",
+ "fuchsia-zircon-sys",
+]
+
+[[package]]
+name = "fuchsia-zircon-sys"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3dcaa9ae7725d12cdb85b3ad99a434db70b468c09ded17e012d86b5c1010f7a7"
+
 [[package]]
 name = "futures"
 version = "0.3.4"
@@ -627,6 +843,18 @@ version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7b0a34e53cf6cdcd0178aa573aed466b646eb3db769570841fda0c7ede375a27"
 
+[[package]]
+name = "futures-timer"
+version = "2.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a1de7508b218029b0f01662ed8f61b1c964b3ae99d6f25462d0f55a595109df6"
+
+[[package]]
+name = "futures-timer"
+version = "3.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e64b03909df88034c26dc1547e8970b91f98bdb65165d6a4e9110d94263dbb2c"
+
 [[package]]
 name = "futures-util"
 version = "0.3.4"
@@ -666,6 +894,38 @@ dependencies = [
  "wasi",
 ]
 
+[[package]]
+name = "globset"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "925aa2cac82d8834e2b2a4415b6f6879757fb5c0928fc445ae76461a12eed8f2"
+dependencies = [
+ "aho-corasick",
+ "bstr",
+ "fnv",
+ "log",
+ "regex",
+]
+
+[[package]]
+name = "h2"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9433d71e471c1736fd5a61b671fc0b148d7a2992f666c958d03cd8feb3b88d1"
+dependencies = [
+ "bytes",
+ "fnv",
+ "futures-core",
+ "futures-sink",
+ "futures-util",
+ "http",
+ "indexmap",
+ "log",
+ "slab",
+ "tokio",
+ "tokio-util",
+]
+
 [[package]]
 name = "hash-db"
 version = "0.15.2"
@@ -697,10 +957,20 @@ version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8e6073d0ca812575946eb5f35ff68dbe519907b25c42530389ff946dc84c6ead"
 dependencies = [
- "ahash",
+ "ahash 0.2.18",
  "autocfg 0.1.7",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "728e7d31e63d53c436094370f1e6fa249f60a4bb318cc5dfbbbe0aa2bc5a29d7"
+dependencies = [
+ "ahash 0.3.2",
+ "autocfg 1.0.0",
+]
+
 [[package]]
 name = "heck"
 version = "0.3.1"
@@ -710,6 +980,15 @@ dependencies = [
  "unicode-segmentation",
 ]
 
+[[package]]
+name = "hermit-abi"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eff2656d88f158ce120947499e971d743c05dbcbed62e5bd2f38f1698bbc3772"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "hex"
 version = "0.4.1"
@@ -737,6 +1016,77 @@ dependencies = [
  "hmac",
 ]
 
+[[package]]
+name = "http"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b708cc7f06493459026f53b9a61a7a121a5d1ec6238dee58ea4941132b30156b"
+dependencies = [
+ "bytes",
+ "fnv",
+ "itoa",
+]
+
+[[package]]
+name = "http-body"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "13d5ff830006f7646652e057693569bfe0d51760c0085a071769d142a205111b"
+dependencies = [
+ "bytes",
+ "http",
+]
+
+[[package]]
+name = "httparse"
+version = "1.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd179ae861f0c2e53da70d892f5f3029f9594be0c41dc5269cd371691b1dc2f9"
+
+[[package]]
+name = "humantime"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df004cfca50ef23c36850aaaa59ad52cc70d0e90243c3c7737a4dd32dc7a3c4f"
+dependencies = [
+ "quick-error",
+]
+
+[[package]]
+name = "hyper"
+version = "0.13.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa1c527bbc634be72aa7ba31e4e4def9bbb020f5416916279b7c705cd838893e"
+dependencies = [
+ "bytes",
+ "futures-channel",
+ "futures-core",
+ "futures-util",
+ "h2",
+ "http",
+ "http-body",
+ "httparse",
+ "itoa",
+ "log",
+ "net2",
+ "pin-project",
+ "time",
+ "tokio",
+ "tower-service",
+ "want",
+]
+
+[[package]]
+name = "idna"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02e2673c30ee86b5b96a9cb52ad15718aa1f966f5ab9ad54a8b95d5ca33120a9"
+dependencies = [
+ "matches",
+ "unicode-bidi",
+ "unicode-normalization",
+]
+
 [[package]]
 name = "impl-codec"
 version = "0.4.2"
@@ -784,12 +1134,36 @@ dependencies = [
  "syn 1.0.14",
 ]
 
+[[package]]
+name = "indexmap"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "076f042c5b7b98f31d205f1249267e12a6518c1481e9dae9764af19b707d2292"
+dependencies = [
+ "autocfg 1.0.0",
+]
+
 [[package]]
 name = "integer-sqrt"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f65877bf7d44897a473350b1046277941cee20b263397e90869c50b6e766088b"
 
+[[package]]
+name = "iovec"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2b3ea6ff95e175473f8ffe6a7eb7c00d054240321b84c57051175fe3c1e075e"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "itoa"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b8b7a7c0c47db5545ed3fef7468ee7bb5b74691498139e4b3f6a20685dc6dd8e"
+
 [[package]]
 name = "js-sys"
 version = "0.3.35"
@@ -799,12 +1173,74 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "jsonrpsee"
+version = "1.0.0"
+source = "git+https://github.com/paritytech/jsonrpsee#de7cbf2b7528802b6c1079de837db1d4f24561a6"
+dependencies = [
+ "async-std",
+ "async-tls",
+ "bs58",
+ "bytes",
+ "fnv",
+ "futures",
+ "futures-timer 3.0.2",
+ "globset",
+ "hashbrown 0.7.0",
+ "hyper",
+ "jsonrpsee-proc-macros",
+ "lazy_static",
+ "log",
+ "parking_lot 0.10.0",
+ "pin-project",
+ "rand 0.7.3",
+ "serde",
+ "serde_json",
+ "smallvec 1.2.0",
+ "soketto",
+ "thiserror",
+ "tokio",
+ "unicase",
+ "url",
+ "webpki",
+]
+
+[[package]]
+name = "jsonrpsee-proc-macros"
+version = "1.0.0"
+source = "git+https://github.com/paritytech/jsonrpsee#de7cbf2b7528802b6c1079de837db1d4f24561a6"
+dependencies = [
+ "Inflector",
+ "proc-macro2 1.0.8",
+ "quote 1.0.2",
+ "syn 1.0.14",
+]
+
 [[package]]
 name = "keccak"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "67c21572b4949434e4fc1e1978b99c5f77064153c59d998bf13ecd96fb5ecba7"
 
+[[package]]
+name = "kernel32-sys"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
+dependencies = [
+ "winapi 0.2.8",
+ "winapi-build",
+]
+
+[[package]]
+name = "kv-log-macro"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8c54d9f465d530a752e6ebdc217e081a7a614b48cb200f6f0aee21ba6bc9aabb"
+dependencies = [
+ "log",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -860,6 +1296,12 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "matches"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7ffc5c5338469d4d3ea17d269fa8ea3512ad247247c30bd2df69e68309ed0a08"
+
 [[package]]
 name = "maybe-uninit"
 version = "2.0.0"
@@ -872,13 +1314,22 @@ version = "2.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3197e20c7edb283f87c071ddfc7a2cca8f8e0b888c242959846a6fce03c72223"
 
+[[package]]
+name = "memoffset"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "75189eb85871ea5c2e2c15abbdd541185f63b408415e5051f5cac122d8c774b9"
+dependencies = [
+ "rustc_version",
+]
+
 [[package]]
 name = "memory-db"
 version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "198831fe8722331a395bc199a5d08efbc197497ef354cb4c77b969c02ffc0fc4"
 dependencies = [
- "ahash",
+ "ahash 0.2.18",
  "hash-db",
  "hashbrown 0.6.3",
  "parity-util-mem",
@@ -896,10 +1347,85 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2b0942b357c1b4d0dc43ba724674ec89c3218e6ca2b3e8269e7cb53bcecd2f6e"
 dependencies = [
- "byteorder",
- "keccak",
- "rand_core 0.4.2",
- "zeroize 1.1.0",
+ "byteorder",
+ "keccak",
+ "rand_core 0.4.2",
+ "zeroize 1.1.0",
+]
+
+[[package]]
+name = "mio"
+version = "0.6.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "302dec22bcf6bae6dfb69c647187f4b4d0fb6f535521f7bc022430ce8e12008f"
+dependencies = [
+ "cfg-if",
+ "fuchsia-zircon",
+ "fuchsia-zircon-sys",
+ "iovec",
+ "kernel32-sys",
+ "libc",
+ "log",
+ "miow",
+ "net2",
+ "slab",
+ "winapi 0.2.8",
+]
+
+[[package]]
+name = "mio-uds"
+version = "0.6.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "966257a94e196b11bb43aca423754d87429960a768de9414f3691d6957abf125"
+dependencies = [
+ "iovec",
+ "libc",
+ "mio",
+]
+
+[[package]]
+name = "miow"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8c1f2f3b1cf331de6896aabf6e9d55dca90356cc9960cca7eaaf408a355ae919"
+dependencies = [
+ "kernel32-sys",
+ "net2",
+ "winapi 0.2.8",
+ "ws2_32-sys",
+]
+
+[[package]]
+name = "net2"
+version = "0.2.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "42550d9fb7b6684a6d404d9fa7250c2eb2646df731d1c06afc06dcee9e1bcf88"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "winapi 0.3.8",
+]
+
+[[package]]
+name = "nix"
+version = "0.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c722bee1037d430d0f8e687bbdbf222f27cc6e4e68d5caf630857bb2b6dbdce"
+dependencies = [
+ "bitflags",
+ "cc",
+ "cfg-if",
+ "libc",
+ "void",
+]
+
+[[package]]
+name = "node-primitives"
+version = "2.0.0"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
+dependencies = [
+ "sp-core",
+ "sp-runtime",
 ]
 
 [[package]]
@@ -915,7 +1441,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2ad2a91a8e869eeb30b9cb3119ae87773a8f4ae617f41b1eb9c154b2905f7bd6"
 dependencies = [
  "memchr",
- "version_check",
+ "version_check 0.1.5",
 ]
 
 [[package]]
@@ -960,6 +1486,16 @@ dependencies = [
  "autocfg 1.0.0",
 ]
 
+[[package]]
+name = "num_cpus"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46203554f085ff89c235cd12f7075f3233af9b11ed7c9e16dfe2560d03313ce6"
+dependencies = [
+ "hermit-abi",
+ "libc",
+]
+
 [[package]]
 name = "once_cell"
 version = "0.1.8"
@@ -975,6 +1511,12 @@ version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d584f08c2d717d5c23a6414fc2822b71c651560713e54fa7eace675f758a355e"
 
+[[package]]
+name = "once_cell"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1c601810575c99596d4afc46f78a678c80105117c379eb3650cf99b8a21ce5b"
+
 [[package]]
 name = "opaque-debug"
 version = "0.2.3"
@@ -1017,7 +1559,7 @@ dependencies = [
 [[package]]
 name = "pallet-session"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -1035,7 +1577,7 @@ dependencies = [
 [[package]]
 name = "pallet-timestamp"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -1128,7 +1670,7 @@ dependencies = [
  "parity-util-mem-derive",
  "parking_lot 0.10.0",
  "primitive-types",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1189,7 +1731,7 @@ dependencies = [
  "rand 0.6.5",
  "rustc_version",
  "smallvec 0.6.13",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1204,7 +1746,7 @@ dependencies = [
  "redox_syscall",
  "rustc_version",
  "smallvec 0.6.13",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1218,7 +1760,7 @@ dependencies = [
  "libc",
  "redox_syscall",
  "smallvec 1.2.0",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1249,7 +1791,7 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "006c038a43a45995a9670da19e67600114740e8511d4333bf97a56e66a7542d9"
 dependencies = [
- "base64",
+ "base64 0.9.3",
  "byteorder",
  "crypto-mac",
  "hmac",
@@ -1258,6 +1800,38 @@ dependencies = [
  "subtle 1.0.0",
 ]
 
+[[package]]
+name = "percent-encoding"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
+
+[[package]]
+name = "pin-project"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7804a463a8d9572f13453c516a5faea534a2403d7ced2f0c7e100eeff072772c"
+dependencies = [
+ "pin-project-internal",
+]
+
+[[package]]
+name = "pin-project-internal"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "385322a45f2ecf3410c68d2a549a4a2685e8051d0f278e39743ff4e451cb9b3f"
+dependencies = [
+ "proc-macro2 1.0.8",
+ "quote 1.0.2",
+ "syn 1.0.14",
+]
+
+[[package]]
+name = "pin-project-lite"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "237844750cfbb86f67afe27eee600dfbbcb6188d734139b534cbfbf4f96792ae"
+
 [[package]]
 name = "pin-utils"
 version = "0.1.0-alpha.4"
@@ -1336,6 +1910,12 @@ dependencies = [
  "unicode-xid 0.2.0",
 ]
 
+[[package]]
+name = "quick-error"
+version = "1.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a1d01941d82fa2ab50be1e79e6714289dd7cde78eba4c074bc5a4374f650dfe0"
+
 [[package]]
 name = "quote"
 version = "0.6.13"
@@ -1364,7 +1944,7 @@ dependencies = [
  "fuchsia-cprng",
  "libc",
  "rand_core 0.3.1",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1383,7 +1963,7 @@ dependencies = [
  "rand_os",
  "rand_pcg",
  "rand_xorshift",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1478,7 +2058,7 @@ checksum = "1166d5c91dc97b88d1decc3285bb0a99ed84b05cfd0bc2341bdf2d43fc41e39b"
 dependencies = [
  "libc",
  "rand_core 0.4.2",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1492,7 +2072,7 @@ dependencies = [
  "libc",
  "rand_core 0.4.2",
  "rdrand",
- "winapi",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1547,6 +2127,21 @@ version = "0.6.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b28dfe3fe9badec5dbf0a79a9cccad2cfc2ab5484bdb3e44cbd1ae8b3ba2be06"
 
+[[package]]
+name = "ring"
+version = "0.16.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "741ba1704ae21999c00942f9f5944f801e977f54302af346b596287599ad1862"
+dependencies = [
+ "cc",
+ "lazy_static",
+ "libc",
+ "spin",
+ "untrusted",
+ "web-sys",
+ "winapi 0.3.8",
+]
+
 [[package]]
 name = "ripemd160"
 version = "0.8.0"
@@ -1588,6 +2183,25 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "rustls"
+version = "0.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b25a18b1bf7387f0145e7f8324e700805aade3842dd3db2e74e4cdeb4677c09e"
+dependencies = [
+ "base64 0.10.1",
+ "log",
+ "ring",
+ "sct",
+ "webpki",
+]
+
+[[package]]
+name = "ryu"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bfa8506c1de11c9c4e4c38863ccbe02a305c8188e85a05a784c9e11e1c3910c8"
+
 [[package]]
 name = "safemem"
 version = "0.3.3"
@@ -1636,6 +2250,16 @@ dependencies = [
  "sha2",
 ]
 
+[[package]]
+name = "sct"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3042af939fca8c3453b7af0f1c66e533a15a86169e39de2657310ade8f98d3c"
+dependencies = [
+ "ring",
+ "untrusted",
+]
+
 [[package]]
 name = "semver"
 version = "0.9.0"
@@ -1687,6 +2311,23 @@ dependencies = [
  "syn 1.0.14",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.48"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9371ade75d4c2d6cb154141b9752cf3781ec9c05e0e5cf35060e1e70ee7b9c25"
+dependencies = [
+ "itoa",
+ "ryu",
+ "serde",
+]
+
+[[package]]
+name = "sha1"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2579985fda508104f7587689507983eadd6a6e84dd35d6d115361f530916fa0d"
+
 [[package]]
 name = "sha2"
 version = "0.8.1"
@@ -1720,6 +2361,25 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5c2fb2ec9bcd216a5b0d0ccf31ab17b5ed1d627960edff65bbe95d3ce221cefc"
 
+[[package]]
+name = "soketto"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1c9dab3f95c9ebdf3a88268c19af668f637a3c5039c2c56ff2d40b1b2d64a25b"
+dependencies = [
+ "base64 0.11.0",
+ "bytes",
+ "futures",
+ "http",
+ "httparse",
+ "log",
+ "rand 0.7.3",
+ "sha1",
+ "smallvec 1.2.0",
+ "static_assertions",
+ "thiserror",
+]
+
 [[package]]
 name = "sourcefile"
 version = "0.1.4"
@@ -1729,7 +2389,7 @@ checksum = "4bf77cb82ba8453b42b6ae1d692e4cdc92f9a47beaf89a847c8be83f4e328ad3"
 [[package]]
 name = "sp-api"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "hash-db",
  "parity-scale-codec",
@@ -1744,7 +2404,7 @@ dependencies = [
 [[package]]
 name = "sp-api-proc-macro"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "blake2-rfc",
  "proc-macro-crate",
@@ -1756,7 +2416,7 @@ dependencies = [
 [[package]]
 name = "sp-application-crypto"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "parity-scale-codec",
  "serde",
@@ -1768,7 +2428,7 @@ dependencies = [
 [[package]]
 name = "sp-arithmetic"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "integer-sqrt",
  "num-traits",
@@ -1804,7 +2464,7 @@ dependencies = [
 [[package]]
 name = "sp-core"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "base58",
  "blake2-rfc",
@@ -1844,7 +2504,7 @@ dependencies = [
 [[package]]
 name = "sp-debug-derive"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "proc-macro2 1.0.8",
  "quote 1.0.2",
@@ -1854,7 +2514,7 @@ dependencies = [
 [[package]]
 name = "sp-externalities"
 version = "0.8.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "environmental",
  "sp-std",
@@ -1864,7 +2524,7 @@ dependencies = [
 [[package]]
 name = "sp-finality-grandpa"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "parity-scale-codec",
  "serde",
@@ -1877,7 +2537,7 @@ dependencies = [
 [[package]]
 name = "sp-inherents"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "derive_more",
  "parity-scale-codec",
@@ -1889,7 +2549,7 @@ dependencies = [
 [[package]]
 name = "sp-io"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "hash-db",
  "libsecp256k1",
@@ -1907,16 +2567,25 @@ dependencies = [
 [[package]]
 name = "sp-panic-handler"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "backtrace",
  "log",
 ]
 
+[[package]]
+name = "sp-rpc"
+version = "2.0.0"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
+dependencies = [
+ "serde",
+ "sp-core",
+]
+
 [[package]]
 name = "sp-runtime"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "impl-trait-for-tuples",
  "log",
@@ -1936,7 +2605,7 @@ dependencies = [
 [[package]]
 name = "sp-runtime-interface"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "parity-scale-codec",
  "primitive-types",
@@ -1950,7 +2619,7 @@ dependencies = [
 [[package]]
 name = "sp-runtime-interface-proc-macro"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "Inflector",
  "proc-macro-crate",
@@ -1962,7 +2631,7 @@ dependencies = [
 [[package]]
 name = "sp-staking"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "parity-scale-codec",
  "sp-runtime",
@@ -1972,7 +2641,7 @@ dependencies = [
 [[package]]
 name = "sp-state-machine"
 version = "0.8.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "hash-db",
  "log",
@@ -1991,12 +2660,12 @@ dependencies = [
 [[package]]
 name = "sp-std"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 
 [[package]]
 name = "sp-storage"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "impl-serde 0.2.3",
  "serde",
@@ -2007,7 +2676,7 @@ dependencies = [
 [[package]]
 name = "sp-timestamp"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "impl-trait-for-tuples",
  "parity-scale-codec",
@@ -2021,7 +2690,7 @@ dependencies = [
 [[package]]
 name = "sp-trie"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "hash-db",
  "memory-db",
@@ -2035,7 +2704,7 @@ dependencies = [
 [[package]]
 name = "sp-version"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "impl-serde 0.2.3",
  "parity-scale-codec",
@@ -2047,7 +2716,7 @@ dependencies = [
 [[package]]
 name = "sp-wasm-interface"
 version = "2.0.0"
-source = "git+https://github.com/paritytech/substrate.git#d78534edc04bb1a2eedf7feac0da9ddf85b348e4"
+source = "git+https://github.com/paritytech/substrate.git#2e8080e2902fc477bbce36512a8f5bcdc4b49f17"
 dependencies = [
  "impl-trait-for-tuples",
  "parity-scale-codec",
@@ -2055,6 +2724,12 @@ dependencies = [
  "wasmi",
 ]
 
+[[package]]
+name = "spin"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
+
 [[package]]
 name = "static_assertions"
 version = "1.1.0"
@@ -2070,6 +2745,12 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "strsim"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
+
 [[package]]
 name = "substrate-bip39"
 version = "0.3.1"
@@ -2082,6 +2763,25 @@ dependencies = [
  "sha2",
 ]
 
+[[package]]
+name = "substrate-bridge"
+version = "0.1.0"
+dependencies = [
+ "async-std",
+ "clap",
+ "ctrlc",
+ "derive_more",
+ "env_logger",
+ "futures",
+ "jsonrpsee",
+ "log",
+ "node-primitives",
+ "serde_json",
+ "sp-core",
+ "sp-rpc",
+ "url",
+]
+
 [[package]]
 name = "subtle"
 version = "1.0.0"
@@ -2140,6 +2840,44 @@ dependencies = [
  "unicode-xid 0.2.0",
 ]
 
+[[package]]
+name = "termcolor"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bb6bfa289a4d7c5766392812c0a1f4c1ba45afa1ad47803c11e1f407d846d75f"
+dependencies = [
+ "winapi-util",
+]
+
+[[package]]
+name = "textwrap"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
+dependencies = [
+ "unicode-width",
+]
+
+[[package]]
+name = "thiserror"
+version = "1.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee14bf8e6767ab4c687c9e8bc003879e042a96fd67a3ba5934eadb6536bef4db"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "1.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7b51e1fbc44b5a0840be594fbc0f960be09050f2617e61e6aa43bef97cd3ef4"
+dependencies = [
+ "proc-macro2 1.0.8",
+ "quote 1.0.2",
+ "syn 1.0.14",
+]
+
 [[package]]
 name = "thread_local"
 version = "1.0.1"
@@ -2149,6 +2887,17 @@ dependencies = [
  "lazy_static",
 ]
 
+[[package]]
+name = "time"
+version = "0.1.42"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "db8dcfca086c1143c9270ac42a2bbd8a7ee477b78ac8e45b19abfb0cbede4b6f"
+dependencies = [
+ "libc",
+ "redox_syscall",
+ "winapi 0.3.8",
+]
+
 [[package]]
 name = "tiny-bip39"
 version = "0.6.2"
@@ -2182,6 +2931,36 @@ dependencies = [
  "crunchy",
 ]
 
+[[package]]
+name = "tokio"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8fdd17989496f49cdc57978c96f0c9fe5e4a58a8bddc6813c449a4624f6a030b"
+dependencies = [
+ "bytes",
+ "fnv",
+ "iovec",
+ "lazy_static",
+ "memchr",
+ "mio",
+ "pin-project-lite",
+ "slab",
+]
+
+[[package]]
+name = "tokio-util"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "571da51182ec208780505a32528fc5512a8fe1443ab960b3f2f3ef093cd16930"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "futures-sink",
+ "log",
+ "pin-project-lite",
+ "tokio",
+]
+
 [[package]]
 name = "toml"
 version = "0.5.6"
@@ -2191,6 +2970,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "tower-service"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e987b6bf443f4b5b3b6f38704195592cca41c5bb7aedd3c3693c7081f8289860"
+
 [[package]]
 name = "tracing"
 version = "0.1.12"
@@ -2253,6 +3038,12 @@ dependencies = [
  "rlp",
 ]
 
+[[package]]
+name = "try-lock"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e604eb7b43c06650e854be16a2a03155743d3752dd1c943f6829e26b7a36e382"
+
 [[package]]
 name = "twox-hash"
 version = "1.5.0"
@@ -2280,12 +3071,45 @@ dependencies = [
  "static_assertions",
 ]
 
+[[package]]
+name = "unicase"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "50f37be617794602aabbeee0be4f259dc1778fabe05e2d67ee8f79326d5cb4f6"
+dependencies = [
+ "version_check 0.9.1",
+]
+
+[[package]]
+name = "unicode-bidi"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "49f2bd0c6468a8230e1db229cff8029217cf623c767ea5d60bfbd42729ea54d5"
+dependencies = [
+ "matches",
+]
+
+[[package]]
+name = "unicode-normalization"
+version = "0.1.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5479532badd04e128284890390c1e876ef7a993d0570b3597ae43dfa1d59afa4"
+dependencies = [
+ "smallvec 1.2.0",
+]
+
 [[package]]
 name = "unicode-segmentation"
 version = "1.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e83e153d1053cbb5a118eeff7fd5be06ed99153f00dbcd8ae310c5fb2b22edc0"
 
+[[package]]
+name = "unicode-width"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "caaa9d531767d1ff2150b9332433f32a24622147e5ebb1f26409d5da67afd479"
+
 [[package]]
 name = "unicode-xid"
 version = "0.1.0"
@@ -2298,12 +3122,57 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"
 
+[[package]]
+name = "untrusted"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "60369ef7a31de49bcb3f6ca728d4ba7300d9a1658f94c727d4cab8c8d9f4aece"
+
+[[package]]
+name = "url"
+version = "2.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "829d4a8476c35c9bf0bbce5a3b23f4106f79728039b726d292bb93bc106787cb"
+dependencies = [
+ "idna",
+ "matches",
+ "percent-encoding",
+]
+
+[[package]]
+name = "vec_map"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
+
 [[package]]
 name = "version_check"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "914b1a6776c4c929a602fafd8bc742e06365d4bcbe48c30f9cca5824f70dc9dd"
 
+[[package]]
+name = "version_check"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "078775d0255232fb988e6fccf26ddc9d1ac274299aaedcedce21c6f72cc533ce"
+
+[[package]]
+name = "void"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
+
+[[package]]
+name = "want"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1ce8a968cb1cd110d136ff8b819a556d6fb6d919363c61534f6860c7eb172ba0"
+dependencies = [
+ "log",
+ "try-lock",
+]
+
 [[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
@@ -2444,6 +3313,25 @@ dependencies = [
  "wasm-bindgen-webidl",
 ]
 
+[[package]]
+name = "webpki"
+version = "0.21.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1f50e1972865d6b1adb54167d1c8ed48606004c2c9d0ea5f1eeb34d95e863ef"
+dependencies = [
+ "ring",
+ "untrusted",
+]
+
+[[package]]
+name = "webpki-roots"
+version = "0.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a262ae37dd9d60f60dd473d1158f9fbebf110ba7b6a5051c8160460f6043718b"
+dependencies = [
+ "webpki",
+]
+
 [[package]]
 name = "weedle"
 version = "0.10.0"
@@ -2453,6 +3341,12 @@ dependencies = [
  "nom",
 ]
 
+[[package]]
+name = "winapi"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
+
 [[package]]
 name = "winapi"
 version = "0.3.8"
@@ -2463,18 +3357,43 @@ dependencies = [
  "winapi-x86_64-pc-windows-gnu",
 ]
 
+[[package]]
+name = "winapi-build"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"
+
 [[package]]
 name = "winapi-i686-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
 
+[[package]]
+name = "winapi-util"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ccfbf554c6ad11084fb7517daca16cfdcaccbdadba4fc336f032a8b12c2ad80"
+dependencies = [
+ "winapi 0.3.8",
+]
+
 [[package]]
 name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
+[[package]]
+name = "ws2_32-sys"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d59cefebd0c892fa2dd6de581e937301d8552cb44489cdff035c6187cb63fa5e"
+dependencies = [
+ "winapi 0.2.8",
+ "winapi-build",
+]
+
 [[package]]
 name = "zeroize"
 version = "0.9.3"
diff --git a/Cargo.toml b/Cargo.toml
index 8945715e9c1f..91e62a33047b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,4 +3,5 @@
 members = [
     "modules/substrate",
     "modules/ethereum",
+    "relays/substrate",
 ]
diff --git a/modules/substrate/src/lib.rs b/modules/substrate/src/lib.rs
index ca3fe2839a56..ad27627f62ca 100644
--- a/modules/substrate/src/lib.rs
+++ b/modules/substrate/src/lib.rs
@@ -247,6 +247,9 @@ mod tests {
 		type MaximumBlockLength = ();
 		type Version = ();
 		type ModuleToIndex = ();
+		type AccountData = ();
+		type OnNewAccount = ();
+		type OnReapAccount = ();
 	}
 
 	impl Trait for Test {}
diff --git a/relays/substrate/Cargo.toml b/relays/substrate/Cargo.toml
new file mode 100644
index 000000000000..d3382cedd462
--- /dev/null
+++ b/relays/substrate/Cargo.toml
@@ -0,0 +1,20 @@
+[package]
+name = "substrate-bridge"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+
+[dependencies]
+async-std = "1.0.1"
+clap = "2.3.3"
+ctrlc = "3.1.3"
+derive_more = "0.99.1"
+env_logger = "0.7.1"
+futures = "0.3.1"
+jsonrpsee = { git = "https://github.com/paritytech/jsonrpsee", features = ["ws"] }
+log = "0.4.8"
+node-primitives = { version = "2.0.0", git = "https://github.com/paritytech/substrate" }
+serde_json = "1.0.41"
+sp-core = { version = "2.0.0", git = "https://github.com/paritytech/substrate.git" }
+sp-rpc = { version = "2.0.0", git = "https://github.com/paritytech/substrate.git" }
+url = "2.1.0"
diff --git a/relays/substrate/README.md b/relays/substrate/README.md
new file mode 100644
index 000000000000..dcbaeaaed5a8
--- /dev/null
+++ b/relays/substrate/README.md
@@ -0,0 +1,32 @@
+# Substrate-to-Substrate Bridge Relay
+
+The bridge relay is a process that connects to running Substrate nodes and sends data over the Substrate-to-Substrate bridge. The process communicates with the nodes over the JSON-RPC interface and reads data from the relays information required by the `bridge` pallet using runtime calls and writes data to the modules by constructing and submitting extrinsics.
+
+For more details, see the [design document](doc/design.md).
+
+## Status
+
+This is a not-in-progress prototype.
+
+## Running in development
+
+Run two development Substrate chains:
+
+```bash
+> TMPDIR=(mktemp -d)
+> cd $TMPDIR
+> substrate build-spec --dev > red-spec.json
+> cp red-spec.json blue-spec.json
+# Modify the chain spec in an editor so that the genesis hashes of the two chains differ.
+# For example, double one of the balances in '$.genesis.runtime.balances.balances'.
+> substrate --chain red-spec.json --alice --base-path ./red --port 30343 --ws-port 9954
+> substrate --chain blue-spec.json --alice --base-path ./blue --port 30353 --ws-port 9964
+```
+
+Now run the bridge relay:
+
+```
+> target/release/substrate-bridge --base-path ./relay \
+    --rpc-url ws://localhost:9954 \
+    --rpc-url ws://localhost:9964
+```
diff --git a/relays/substrate/src/bridge.rs b/relays/substrate/src/bridge.rs
new file mode 100644
index 000000000000..7a733c5862e5
--- /dev/null
+++ b/relays/substrate/src/bridge.rs
@@ -0,0 +1,391 @@
+use crate::error::Error;
+use crate::rpc::{self, SubstrateRPC};
+use crate::params::{RPCUrlParam, Params};
+
+use futures::{prelude::*, channel::{mpsc, oneshot}, future, select};
+use jsonrpsee::{
+	core::client::{RawClientError, RawClientEvent, RawClientRequestId, RawClientSubscription},
+	ws::{WsRawClient, WsConnecError, ws_raw_client},
+};
+use node_primitives::{Hash, Header};
+use std::cell::RefCell;
+use std::collections::HashMap;
+use std::pin::Pin;
+use sp_core::Bytes;
+
+type ChainId = Hash;
+
+struct BridgeState {
+	channel: mpsc::Sender<Event>,
+	locally_finalized_head_on_bridged_chain: Header,
+}
+
+struct ChainState {
+	current_finalized_head: Header,
+	bridges: HashMap<ChainId, BridgeState>,
+}
+
+enum Event {
+	SubmitExtrinsic(Bytes),
+}
+
+struct Chain {
+	url: String,
+	client: WsRawClient,
+	sender: mpsc::Sender<Event>,
+	receiver: mpsc::Receiver<Event>,
+	genesis_hash: Hash,
+	state: ChainState,
+}
+
+async fn init_rpc_connection(url: &RPCUrlParam) -> Result<Chain, Error> {
+	let url_str = url.to_string();
+	log::debug!("Connecting to {}", url_str);
+
+	// Skip the leading "ws://" and trailing "/".
+	let url_without_scheme = &url_str[5..(url_str.len() - 1)];
+	let mut client = ws_raw_client(url_without_scheme)
+		.await
+		.map_err(|err| Error::WsConnectionError(err.to_string()))?;
+
+	let genesis_hash = rpc::genesis_block_hash(&mut client)
+		.await
+		.map_err(|e| Error::RPCError(e.to_string()))?
+		.ok_or_else(|| Error::InvalidChainState(format!(
+			"chain with RPC URL {} is missing a genesis block hash",
+			url_str,
+		)))?;
+
+	let latest_finalized_hash = SubstrateRPC::chain_finalized_head(&mut client)
+		.await
+		.map_err(|e| Error::RPCError(e.to_string()))?;
+	let latest_finalized_header = SubstrateRPC::chain_header(
+		&mut client,
+		Some(latest_finalized_hash)
+	)
+		.await
+		.map_err(|e| Error::RPCError(e.to_string()))?
+		.ok_or_else(|| Error::InvalidChainState(format!(
+			"chain {} is missing header for finalized block hash {}",
+			genesis_hash, latest_finalized_hash
+		)))?;
+
+	let (sender, receiver) = mpsc::channel(0);
+
+	Ok(Chain {
+		url: url_str,
+		client,
+		sender,
+		receiver,
+		genesis_hash,
+		state: ChainState {
+			current_finalized_head: latest_finalized_header,
+			bridges: HashMap::new(),
+		}
+	})
+}
+
+/// Returns IDs of the bridged chains.
+async fn read_bridges(chain: &mut Chain, chain_ids: &[Hash])
+	-> Result<Vec<Hash>, Error>
+{
+	// This should make an RPC call to read this information from the bridge pallet state.
+	// For now, just pretend every chain is bridged to every other chain.
+	//
+	// TODO: The correct thing.
+	Ok(
+		chain_ids
+			.iter()
+			.cloned()
+			.filter(|&chain_id| chain_id != chain.genesis_hash)
+			.collect()
+	)
+}
+
+pub async fn run_async(
+	params: Params,
+	exit: Box<dyn Future<Output=()> + Unpin + Send>
+) -> Result<(), Error>
+{
+	let chains = init_chains(&params).await?;
+
+	let (chain_tasks, exit_signals) = chains.into_iter()
+		.map(|(chain_id, chain_cell)| {
+			let chain = chain_cell.into_inner();
+			let (task_exit_signal, task_exit_receiver) = oneshot::channel();
+			let task_exit = Box::new(task_exit_receiver.map(|result| {
+				result.expect("task_exit_signal is not dropped before send() is called")
+			}));
+			let chain_task = async_std::task::spawn(async move {
+				if let Err(err) = chain_task(chain_id, chain, task_exit).await {
+					log::error!("Error in task for chain {}: {}", chain_id, err);
+				}
+			});
+			(chain_task, task_exit_signal)
+		})
+		.unzip::<_, _, Vec<_>, Vec<_>>();
+
+	async_std::task::spawn(async move {
+		exit.await;
+		for exit_signal in exit_signals {
+			let _ = exit_signal.send(());
+		}
+	});
+
+	future::join_all(chain_tasks).await;
+	Ok(())
+}
+
+fn initial_next_events<'a>(chains: &'a HashMap<ChainId, RefCell<Chain>>)
+	-> Vec<Pin<Box<dyn Future<Output=Result<(ChainId, RawClientEvent), Error>> + 'a>>>
+{
+	chains.values()
+		.map(|chain_cell| async move {
+			let mut chain = chain_cell.borrow_mut();
+			let event = chain.client.next_event()
+				.await
+				.map_err(|err| Error::RPCError(err.to_string()))?;
+			Ok((chain.genesis_hash, event))
+		})
+		.map(|fut| Box::pin(fut) as Pin<Box<dyn Future<Output=_>>>)
+		.collect()
+}
+
+async fn next_event<'a>(
+	next_events: Vec<Pin<Box<dyn Future<Output=Result<(ChainId, RawClientEvent), Error>> + 'a>>>,
+	chains: &'a HashMap<ChainId, RefCell<Chain>>,
+)
+	-> (
+		Result<(Hash, RawClientEvent), Error>,
+		Vec<Pin<Box<dyn Future<Output=Result<(ChainId, RawClientEvent), Error>> +'a>>>
+	)
+{
+	let (result, _, mut rest) = future::select_all(next_events).await;
+
+	match result {
+		Ok((chain_id, _)) => {
+			let fut = async move {
+				let chain_cell = chains.get(&chain_id)
+					.expect("chain must be in the map as a function precondition; qed");
+				let mut chain = chain_cell.borrow_mut();
+				let event = chain.client.next_event()
+					.await
+					.map_err(|err| Error::RPCError(err.to_string()))?;
+				Ok((chain_id, event))
+			};
+			rest.push(Box::pin(fut));
+		}
+		Err(ref err) => log::warn!("error in RPC connection with a chain: {}", err),
+	}
+
+	(result, rest)
+}
+
+async fn init_chains(params: &Params) -> Result<HashMap<ChainId, RefCell<Chain>>, Error> {
+	let chains = future::join_all(params.rpc_urls.iter().map(init_rpc_connection))
+		.await
+		.into_iter()
+		.map(|result| result.map(|chain| (chain.genesis_hash, RefCell::new(chain))))
+		.collect::<Result<HashMap<_, _>, _>>()?;
+
+	// TODO: Remove when read_bridges is implemented correctly.
+	let chain_ids = chains.keys()
+		.cloned()
+		.collect::<Vec<_>>();
+	// let chain_ids_slice = chain_ids.as_slice();
+
+	for (&chain_id, chain_cell) in chains.iter() {
+		let mut chain = chain_cell.borrow_mut();
+		for bridged_chain_id in read_bridges(&mut chain, &chain_ids).await? {
+			if chain_id == bridged_chain_id {
+				log::warn!("chain {} has a bridge to itself", chain_id);
+				continue;
+			}
+
+			if let Some(bridged_chain_cell) = chains.get(&bridged_chain_id) {
+				let bridged_chain = bridged_chain_cell.borrow_mut();
+
+				// TODO: Get this from RPC to runtime API.
+				let genesis_head = SubstrateRPC::chain_header(&mut chain.client, chain_id)
+					.await
+					.map_err(|e| Error::RPCError(e.to_string()))?
+					.ok_or_else(|| Error::InvalidChainState(format!(
+						"chain {} is missing a genesis block header", chain_id
+					)))?;
+
+				let channel = chain.sender.clone();
+				chain.state.bridges.insert(bridged_chain_id, BridgeState {
+					channel,
+					locally_finalized_head_on_bridged_chain: genesis_head,
+				});
+
+				// The conditional ensures that we don't log twice per pair of chains.
+				if chain_id.as_ref() < bridged_chain_id.as_ref() {
+					log::info!("initialized bridge between {} and {}", chain_id, bridged_chain_id);
+				}
+			}
+		}
+	}
+
+	Ok(chains)
+}
+
+async fn setup_subscriptions(chain: &mut Chain)
+	-> Result<(RawClientRequestId, RawClientRequestId), RawClientError<WsConnecError>>
+{
+	let new_heads_subscription_id = chain.client
+		.start_subscription(
+			"chain_subscribeNewHeads",
+			jsonrpsee::core::common::Params::None,
+		)
+		.await
+		.map_err(RawClientError::Inner)?;
+
+	let finalized_heads_subscription_id = chain.client
+		.start_subscription(
+			"chain_subscribeFinalizedHeads",
+			jsonrpsee::core::common::Params::None,
+		)
+		.await
+		.map_err(RawClientError::Inner)?;
+
+	let new_heads_subscription =
+		chain.client.subscription_by_id(new_heads_subscription_id)
+			.expect("subscription_id was returned from start_subscription above; qed");
+	let new_heads_subscription = match new_heads_subscription {
+		RawClientSubscription::Active(_) => {}
+		RawClientSubscription::Pending(subscription) => {
+			subscription.wait().await?;
+		}
+	};
+
+	let finalized_heads_subscription =
+		chain.client.subscription_by_id(finalized_heads_subscription_id)
+			.expect("subscription_id was returned from start_subscription above; qed");
+	let finalized_heads_subscription = match finalized_heads_subscription {
+		RawClientSubscription::Active(subscription) => {}
+		RawClientSubscription::Pending(subscription) => {
+			subscription.wait().await?;
+		}
+	};
+
+	Ok((new_heads_subscription_id, finalized_heads_subscription_id))
+}
+
+async fn handle_rpc_event(
+	chain_id: ChainId,
+	chain: &mut Chain,
+	event: RawClientEvent,
+	new_heads_subscription_id: RawClientRequestId,
+	finalized_heads_subscription_id: RawClientRequestId,
+) -> Result<(), Error>
+{
+	match event {
+		RawClientEvent::SubscriptionNotif { request_id, result } =>
+			if request_id == new_heads_subscription_id {
+				let header: Header = serde_json::from_value(result)
+					.map_err(Error::SerializationError)?;
+				log::info!("Received new head {:?} on chain {}", header, chain_id);
+			} else if request_id == finalized_heads_subscription_id {
+				let header: Header = serde_json::from_value(result)
+					.map_err(Error::SerializationError)?;
+				log::info!("Received finalized head {:?} on chain {}", header, chain_id);
+
+				// let old_finalized_head = chain_state.current_finalized_head;
+				chain.state.current_finalized_head = header;
+				for (bridged_chain_id, bridged_chain) in chain.state.bridges.iter_mut() {
+					if bridged_chain.locally_finalized_head_on_bridged_chain.number <
+						chain.state.current_finalized_head.number {
+						// Craft and submit an extrinsic over RPC
+						log::info!("Sending command to submit extrinsic to chain {}", chain_id);
+						let mut send_event = bridged_chain.channel
+							.send(Event::SubmitExtrinsic(Bytes(Vec::new())))
+							.fuse();
+
+						// Continue processing events from other chain tasks while waiting to send
+						// event to other chain task in order to prevent deadlocks.
+						loop {
+							select! {
+								result = send_event => {
+									result.map_err(Error::ChannelError)?;
+									break;
+								}
+								event = chain.receiver.next().fuse() => {
+									let event = event
+										.expect("stream will never close as the chain has an mpsc Sender");
+									handle_bridge_event(chain_id, &mut chain.client, event)
+										.await?;
+								}
+								// TODO: exit
+							}
+						}
+					}
+				}
+			} else {
+				return Err(Error::RPCError(format!(
+					"unexpected subscription response with request ID {:?}", request_id
+				)));
+			},
+		_ => return Err(Error::RPCError(format!(
+			"unexpected RPC event from chain {}: {:?}", chain_id, event
+		))),
+	}
+	Ok(())
+}
+
+// Let's say this never sends over a channel (ie. cannot block on another task).
+async fn handle_bridge_event(
+	chain_id: ChainId,
+	rpc_client: &mut WsRawClient,
+	event: Event,
+) -> Result<(), Error>
+{
+	match event {
+		Event::SubmitExtrinsic(data) => {
+			log::info!("Submitting extrinsic to chain {}", chain_id);
+			if let Err(err) = SubstrateRPC::author_submit_extrinsic(rpc_client, data).await {
+				log::error!("failed to submit extrinsic: {}", err);
+			}
+		}
+	}
+	Ok(())
+}
+
+async fn chain_task(
+	chain_id: ChainId,
+	mut chain: Chain,
+	exit: impl Future<Output=()> + Unpin + Send
+) -> Result<(), Error>
+{
+	let (new_heads_subscription_id, finalized_heads_subscription_id) =
+		setup_subscriptions(&mut chain)
+			.await
+			.map_err(|e| Error::RPCError(e.to_string()))?;
+
+	let mut exit = exit.fuse();
+	loop {
+		select! {
+			result = chain.client.next_event().fuse() => {
+				let event = result.map_err(|e| Error::RPCError(e.to_string()))?;
+				handle_rpc_event(
+					chain_id,
+					&mut chain,
+					event,
+					new_heads_subscription_id,
+					finalized_heads_subscription_id,
+				).await?;
+			}
+			event = chain.receiver.next().fuse() => {
+				let event = event
+					.expect("stream will never close as the chain has an mpsc Sender");
+				handle_bridge_event(chain_id, &mut chain.client, event)
+					.await?;
+			}
+			_ = exit => {
+				log::debug!("Received exit signal, shutting down task for chain {}", chain_id);
+				break;
+			}
+		}
+	}
+	Ok(())
+}
diff --git a/relays/substrate/src/error.rs b/relays/substrate/src/error.rs
new file mode 100644
index 000000000000..a612c84707d6
--- /dev/null
+++ b/relays/substrate/src/error.rs
@@ -0,0 +1,31 @@
+use futures::channel::mpsc;
+
+#[derive(Debug, derive_more::Display)]
+pub enum Error {
+	#[display(fmt = "invalid RPC URL: {}", _0)]
+	UrlError(String),
+	#[display(fmt = "RPC response indicates invalid chain state: {}", _0)]
+	InvalidChainState(String),
+	#[display(fmt = "could not make RPC call: {}", _0)]
+	RPCError(String),
+	#[display(fmt = "could not connect to RPC URL: {}", _0)]
+	WsConnectionError(String),
+	#[display(fmt = "unexpected client event from RPC URL {}: {:?}", _0, _1)]
+	UnexpectedClientEvent(String, String),
+	#[display(fmt = "serialization error: {}", _0)]
+	SerializationError(serde_json::error::Error),
+	#[display(fmt = "invalid event received from bridged chain: {}", _0)]
+	InvalidBridgeEvent(String),
+	#[display(fmt = "error sending over MPSC channel: {}", _0)]
+	ChannelError(mpsc::SendError),
+}
+
+impl std::error::Error for Error {
+	fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+		match self {
+			Error::SerializationError(err) => Some(err),
+			Error::ChannelError(err) => Some(err),
+			_ => None,
+		}
+	}
+}
diff --git a/relays/substrate/src/main.rs b/relays/substrate/src/main.rs
new file mode 100644
index 000000000000..bfa183cb2e50
--- /dev/null
+++ b/relays/substrate/src/main.rs
@@ -0,0 +1,80 @@
+mod bridge;
+mod error;
+mod params;
+mod rpc;
+
+use bridge::run_async;
+use params::{Params, RPCUrlParam};
+
+use clap::{App, Arg, value_t, values_t};
+use futures::{prelude::*, channel};
+use std::cell::Cell;
+use std::process;
+
+fn main() {
+	let params = parse_args();
+	env_logger::init();
+	let exit = setup_exit_handler();
+
+	let result = async_std::task::block_on(async move {
+		run_async(params, exit).await
+	});
+	if let Err(err) = result {
+		log::error!("{}", err);
+		process::exit(1);
+	}
+}
+
+fn parse_args() -> Params {
+	let matches = App::new("substrate-bridge")
+		.version("1.0")
+		.author("Parity Technologies")
+		.about("Bridges Substrates, duh")
+		.arg(
+			Arg::with_name("base-path")
+				.long("base-path")
+				.value_name("DIRECTORY")
+				.required(true)
+				.help("Sets the base path")
+				.takes_value(true),
+		)
+		.arg(
+			Arg::with_name("rpc-url")
+				.long("rpc-url")
+				.value_name("HOST[:PORT]")
+				.help("The URL of a bridged Substrate node")
+				.takes_value(true)
+				.multiple(true)
+		)
+		.get_matches();
+
+	let base_path = value_t!(matches, "base-path", String)
+		.unwrap_or_else(|e| e.exit());
+	let rpc_urls = values_t!(matches, "rpc-url", RPCUrlParam)
+		.unwrap_or_else(|e| e.exit());
+
+	Params {
+		base_path,
+		rpc_urls,
+	}
+}
+
+fn setup_exit_handler() -> Box<dyn Future<Output=()> + Unpin + Send> {
+	let (exit_sender, exit_receiver) = channel::oneshot::channel();
+	let exit_sender = Cell::new(Some(exit_sender));
+
+	ctrlc::set_handler(move || {
+		if let Some(exit_sender) = exit_sender.take() {
+			if let Err(()) = exit_sender.send(()) {
+				log::warn!("failed to send exit signal");
+			}
+		}
+	})
+		.expect("must be able to set Ctrl-C handler");
+
+	Box::new(exit_receiver.map(|result| {
+		result.expect(
+			"exit_sender cannot be dropped as it is moved into a globally-referenced closure"
+		)
+	}))
+}
diff --git a/relays/substrate/src/params.rs b/relays/substrate/src/params.rs
new file mode 100644
index 000000000000..019581eb8c4b
--- /dev/null
+++ b/relays/substrate/src/params.rs
@@ -0,0 +1,75 @@
+use crate::error::Error;
+
+use url::Url;
+use std::str::FromStr;
+
+const DEFAULT_WS_PORT: u16 = 9944;
+
+#[derive(Debug, Clone)]
+pub struct Params {
+	pub base_path: String,
+	pub rpc_urls: Vec<RPCUrlParam>,
+}
+
+#[derive(Debug, Clone)]
+pub struct RPCUrlParam {
+	url: Url,
+}
+
+impl ToString for RPCUrlParam {
+	fn to_string(&self) -> String {
+		self.url.to_string()
+	}
+}
+
+impl FromStr for RPCUrlParam {
+	type Err = Error;
+
+	fn from_str(url_str: &str) -> Result<Self, Self::Err> {
+		let mut url = Url::parse(url_str)
+			.map_err(|e| Error::UrlError(format!("could not parse {}: {}", url_str, e)))?;
+
+		if url.scheme() != "ws" {
+			return Err(Error::UrlError(format!("must have scheme ws, found {}", url.scheme())));
+		}
+
+		if url.port().is_none() {
+			url.set_port(Some(DEFAULT_WS_PORT))
+				.expect("the scheme is checked above to be ws; qed");
+		}
+
+		if url.path() != "/" {
+			return Err(Error::UrlError(format!("cannot have a path, found {}", url.path())));
+		}
+		if let Some(query) = url.query() {
+			return Err(Error::UrlError(format!("cannot have a query, found {}", query)));
+		}
+		if let Some(fragment) = url.fragment() {
+			return Err(Error::UrlError(format!("cannot have a fragment, found {}", fragment)));
+		}
+
+		Ok(RPCUrlParam { url })
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+
+	#[test]
+	fn rpc_url_from_str() {
+		assert_eq!(
+			RPCUrlParam::from_str("ws://127.0.0.1").unwrap().to_string(),
+			"ws://127.0.0.1:9944/"
+		);
+		assert_eq!(
+			RPCUrlParam::from_str("ws://127.0.0.1/").unwrap().to_string(),
+			"ws://127.0.0.1:9944/"
+		);
+		assert_eq!(
+			RPCUrlParam::from_str("ws://127.0.0.1:4499").unwrap().to_string(),
+			"ws://127.0.0.1:4499/"
+		);
+		assert!(RPCUrlParam::from_str("http://127.0.0.1").is_err());
+	}
+}
diff --git a/relays/substrate/src/rpc.rs b/relays/substrate/src/rpc.rs
new file mode 100644
index 000000000000..575419e3c5f0
--- /dev/null
+++ b/relays/substrate/src/rpc.rs
@@ -0,0 +1,29 @@
+use jsonrpsee::core::client::{RawClient, RawClientError, TransportClient};
+use node_primitives::{BlockNumber, Hash, Header};
+use sp_core::Bytes;
+use sp_rpc::number::NumberOrHex;
+
+jsonrpsee::rpc_api! {
+	pub SubstrateRPC {
+		#[rpc(method = "author_submitExtrinsic", positional_params)]
+		fn author_submit_extrinsic(extrinsic: Bytes) -> Hash;
+
+		#[rpc(method = "chain_getFinalizedHead")]
+		fn chain_finalized_head() -> Hash;
+
+		#[rpc(method = "chain_getBlockHash", positional_params)]
+		fn chain_block_hash(id: Option<NumberOrHex<BlockNumber>>) -> Option<Hash>;
+
+		#[rpc(method = "chain_getHeader", positional_params)]
+		fn chain_header(hash: Option<Hash>) -> Option<Header>;
+
+		#[rpc(positional_params)]
+		fn state_call(name: String, bytes: Bytes, hash: Option<Hash>) -> Bytes;
+	}
+}
+
+pub async fn genesis_block_hash<R: TransportClient>(client: &mut RawClient<R>)
+	-> Result<Option<Hash>, RawClientError<R::Error>>
+{
+	SubstrateRPC::chain_block_hash(client, Some(NumberOrHex::Number(0))).await
+}