From 0ec265380c9108bde90cb4290873e166b23cd0c1 Mon Sep 17 00:00:00 2001
From: Ludo Galabru <ludo@hiro.so>
Date: Mon, 3 Apr 2023 10:45:29 -0400
Subject: [PATCH] feat: start investigating zmq signaling

---
 Cargo.lock                                    | 342 +++++++++++++++---
 .../chainhook-event-observer/Cargo.toml       |   1 +
 .../src/observer/mod.rs                       |  19 +
 3 files changed, 310 insertions(+), 52 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index e520a84a..d15b1eaf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -32,7 +32,7 @@ version = "0.7.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9e8b47f52ea9bae42228d07ec09eb676433d7c4ed1ebdf0f1d1c29ed446f1ab8"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "cipher",
  "cpufeatures",
  "opaque-debug 0.3.0",
@@ -52,6 +52,15 @@ dependencies = [
  "subtle 2.4.1",
 ]
 
+[[package]]
+name = "ahash"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e8fd72866655d1904d6b0997d0b07ba561047d070fbe29de039031c641b61217"
+dependencies = [
+ "const-random",
+]
+
 [[package]]
 name = "ahash"
 version = "0.7.6"
@@ -152,6 +161,19 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "asynchronous-codec"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "06a0daa378f5fd10634e44b0a29b2a87b890657658e072a30d6f26e57ddee182"
+dependencies = [
+ "bytes",
+ "futures-sink",
+ "futures-util",
+ "memchr",
+ "pin-project-lite",
+]
+
 [[package]]
 name = "atomic"
 version = "0.5.1"
@@ -186,7 +208,7 @@ checksum = "233d376d6d185f2a3093e58f283f60f880315b6c60075b01f36b3b85154564ca"
 dependencies = [
  "addr2line",
  "cc",
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "miniz_oxide",
  "object",
@@ -411,6 +433,12 @@ version = "1.0.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e9f73505338f7d905b19d18738976aae232eb46b8efc15554ffc56deb5d9ebe4"
 
+[[package]]
+name = "cfg-if"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -430,7 +458,7 @@ dependencies = [
  "clarinet-files",
  "clarity-repl",
  "criterion",
- "crossbeam-channel",
+ "crossbeam-channel 0.5.6",
  "csv",
  "ctrlc",
  "flate2",
@@ -449,7 +477,7 @@ dependencies = [
  "tar",
  "tokio",
  "toml",
- "uuid",
+ "uuid 1.3.0",
 ]
 
 [[package]]
@@ -467,7 +495,7 @@ dependencies = [
  "clap_generate",
  "clarinet-utils",
  "clarity-repl",
- "crossbeam-channel",
+ "crossbeam-channel 0.5.6",
  "ctrlc",
  "futures",
  "hex",
@@ -490,6 +518,7 @@ dependencies = [
  "threadpool",
  "tokio",
  "toml",
+ "zeromq",
 ]
 
 [[package]]
@@ -676,7 +705,7 @@ dependencies = [
  "sha2 0.10.6",
  "sha3 0.9.1",
  "tokio",
- "tokio-util",
+ "tokio-util 0.7.2",
 ]
 
 [[package]]
@@ -742,6 +771,28 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "const-random"
+version = "0.1.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "368a7a772ead6ce7e1de82bfb04c485f3db8ec744f72925af5735e29a22cc18e"
+dependencies = [
+ "const-random-macro",
+ "proc-macro-hack",
+]
+
+[[package]]
+name = "const-random-macro"
+version = "0.1.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9d7d6ab3c3a2282db210df5f02c4dab6e0a7057af0fb7ebd4070f30fe05c0ddb"
+dependencies = [
+ "getrandom 0.2.8",
+ "once_cell",
+ "proc-macro-hack",
+ "tiny-keccak",
+]
+
 [[package]]
 name = "const_fn"
 version = "0.4.9"
@@ -797,7 +848,7 @@ version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b540bd8bc810d3885c6ea91e2018302f68baba2129ab3e88f32389ee9370880d"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
 ]
 
 [[package]]
@@ -836,14 +887,49 @@ dependencies = [
  "itertools",
 ]
 
+[[package]]
+name = "crossbeam"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69323bff1fb41c635347b8ead484a5ca6c3f11914d784170b158d8449ab07f8e"
+dependencies = [
+ "cfg-if 0.1.10",
+ "crossbeam-channel 0.4.4",
+ "crossbeam-deque 0.7.4",
+ "crossbeam-epoch 0.8.2",
+ "crossbeam-queue",
+ "crossbeam-utils 0.7.2",
+]
+
+[[package]]
+name = "crossbeam-channel"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b153fe7cbef478c567df0f972e02e6d736db11affe43dfc9c56a9374d1adfb87"
+dependencies = [
+ "crossbeam-utils 0.7.2",
+ "maybe-uninit",
+]
+
 [[package]]
 name = "crossbeam-channel"
 version = "0.5.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c2dd04ddaf88237dc3b8d8f9a3c1004b506b54b3313403944054d23c0870c521"
 dependencies = [
- "cfg-if",
- "crossbeam-utils",
+ "cfg-if 1.0.0",
+ "crossbeam-utils 0.8.14",
+]
+
+[[package]]
+name = "crossbeam-deque"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c20ff29ded3204c5106278a81a38f4b482636ed4fa1e6cfbeef193291beb29ed"
+dependencies = [
+ "crossbeam-epoch 0.8.2",
+ "crossbeam-utils 0.7.2",
+ "maybe-uninit",
 ]
 
 [[package]]
@@ -852,9 +938,24 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "715e8152b692bba2d374b53d4875445368fdf21a94751410af607a5ac677d1fc"
 dependencies = [
- "cfg-if",
- "crossbeam-epoch",
- "crossbeam-utils",
+ "cfg-if 1.0.0",
+ "crossbeam-epoch 0.9.13",
+ "crossbeam-utils 0.8.14",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "058ed274caafc1f60c4997b5fc07bf7dc7cca454af7c6e81edffe5f33f70dace"
+dependencies = [
+ "autocfg",
+ "cfg-if 0.1.10",
+ "crossbeam-utils 0.7.2",
+ "lazy_static",
+ "maybe-uninit",
+ "memoffset 0.5.6",
+ "scopeguard",
 ]
 
 [[package]]
@@ -864,19 +965,41 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "01a9af1f4c2ef74bb8aa1f7e19706bc72d03598c8a570bb5de72243c7a9d9d5a"
 dependencies = [
  "autocfg",
- "cfg-if",
- "crossbeam-utils",
+ "cfg-if 1.0.0",
+ "crossbeam-utils 0.8.14",
  "memoffset 0.7.1",
  "scopeguard",
 ]
 
+[[package]]
+name = "crossbeam-queue"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "774ba60a54c213d409d5353bda12d49cd68d14e45036a285234c8d6f91f92570"
+dependencies = [
+ "cfg-if 0.1.10",
+ "crossbeam-utils 0.7.2",
+ "maybe-uninit",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3c7c73a2d1e9fc0886a08b93e98eb643461230d5f1925e4036204d5f2e261a8"
+dependencies = [
+ "autocfg",
+ "cfg-if 0.1.10",
+ "lazy_static",
+]
+
 [[package]]
 name = "crossbeam-utils"
 version = "0.8.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4fb766fa798726286dbbb842f174001dab8abc7b627a1dd86e0b7222a95d929f"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
 ]
 
 [[package]]
@@ -1049,6 +1172,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "dashmap"
+version = "3.11.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0f260e2fc850179ef410018660006951c1b55b79e8087e87111a2c388994b9b5"
+dependencies = [
+ "ahash 0.3.8",
+ "cfg-if 0.1.10",
+ "num_cpus",
+]
+
 [[package]]
 name = "debug_types"
 version = "1.0.0"
@@ -1128,7 +1262,7 @@ version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b98cf8ebf19c3d1b223e151f99a4f9f0690dca41414773390fc824184ac833e1"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "dirs-sys-next",
 ]
 
@@ -1186,7 +1320,7 @@ version = "0.8.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9852635589dc9f9ea1b6fe9f05b50ef208c85c834a562f0c6abb1c475736ec2b"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
 ]
 
 [[package]]
@@ -1195,6 +1329,17 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c34f04666d835ff5d62e058c3995147c06f42fe86ff053337632bca83e42702d"
 
+[[package]]
+name = "enum-primitive-derive"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c375b9c5eadb68d0a6efee2999fef292f45854c3444c86f09d8ab086ba942b0e"
+dependencies = [
+ "num-traits",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "errno"
 version = "0.2.8"
@@ -1259,7 +1404,7 @@ version = "3.0.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bb21c69b9fea5e15dbc1049e4b77145dd0ba1c84019c488102de0dc4ea4b0a27"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "rustix",
  "windows-sys 0.42.0",
 ]
@@ -1284,7 +1429,7 @@ version = "0.2.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4e884668cd0c7480504233e951174ddc3b382f7c2666e3b7310b5c4e7b0c37f9"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "redox_syscall",
  "windows-sys 0.42.0",
@@ -1470,7 +1615,7 @@ version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "wasi 0.9.0+wasi-snapshot-preview1",
 ]
@@ -1481,7 +1626,7 @@ version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c05aeb6a22b8f62540c194aac980f2115af067bfe15a0734d7277a768d396b31"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "js-sys",
  "libc",
  "wasi 0.11.0+wasi-snapshot-preview1",
@@ -1525,7 +1670,7 @@ dependencies = [
  "indexmap",
  "slab",
  "tokio",
- "tokio-util",
+ "tokio-util 0.7.2",
  "tracing",
 ]
 
@@ -1541,7 +1686,7 @@ version = "0.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
 dependencies = [
- "ahash",
+ "ahash 0.7.6",
 ]
 
 [[package]]
@@ -1834,7 +1979,7 @@ version = "0.1.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7a5bbe824c507c5da5956355e86a746d82e0e1464f65d862cc5e71da70e94b2c"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
 ]
 
 [[package]]
@@ -2091,7 +2236,7 @@ version = "0.4.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "abb12e687cfb44aa40f41fc3978ef76448f9b6038cad6aef4259d3c095a2382e"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
 ]
 
 [[package]]
@@ -2100,7 +2245,7 @@ version = "0.5.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ff50ecb28bb86013e935fb6683ab1f6d3a20016f123c76fd4c27470076ac30f5"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "generator",
  "scoped-tls",
  "serde",
@@ -2130,6 +2275,15 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
 
+[[package]]
+name = "memoffset"
+version = "0.5.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "043175f069eda7b85febe4a74abbaeff828d9f8b448515d3151a14a3542811aa"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "memoffset"
 version = "0.6.5"
@@ -2197,7 +2351,7 @@ dependencies = [
  "mime",
  "spin 0.9.4",
  "tokio",
- "tokio-util",
+ "tokio-util 0.7.2",
  "version_check",
 ]
 
@@ -2245,7 +2399,7 @@ checksum = "8f3790c00a0150112de0f4cd161e3d7fc4b2d8a5542ffc35f099a2562aecb35c"
 dependencies = [
  "bitflags",
  "cc",
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "memoffset 0.6.5",
 ]
@@ -2258,7 +2412,7 @@ checksum = "f346ff70e7dbfd675fe90590b92d59ef2de15a8779ae305ebcbfd3f0caf59be4"
 dependencies = [
  "autocfg",
  "bitflags",
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
 ]
 
@@ -2368,7 +2522,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b102428fd03bc5edf97f62620f7298614c45cedf287c271e7ed450bbaf83f2e1"
 dependencies = [
  "bitflags",
- "cfg-if",
+ "cfg-if 1.0.0",
  "foreign-types",
  "libc",
  "once_cell",
@@ -2424,6 +2578,17 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b15813163c1d831bf4a13c3610c05c0d03b39feb07f7e09fa234dac9b15aaf39"
 
+[[package]]
+name = "parking_lot"
+version = "0.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7d17b78036a60663b797adeaee46f5c9dfebb86948d1255007a1d6be0271ff99"
+dependencies = [
+ "instant",
+ "lock_api",
+ "parking_lot_core 0.8.6",
+]
+
 [[package]]
 name = "parking_lot"
 version = "0.12.1"
@@ -2431,7 +2596,21 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3742b2c103b9f06bc9fff0a37ff4912935851bee6d36f3c02bcc755bcfec228f"
 dependencies = [
  "lock_api",
- "parking_lot_core",
+ "parking_lot_core 0.9.5",
+]
+
+[[package]]
+name = "parking_lot_core"
+version = "0.8.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "60a2cfe6f0ad2bfc16aefa463b497d5c7a5ecd44a23efa72aa342d90177356dc"
+dependencies = [
+ "cfg-if 1.0.0",
+ "instant",
+ "libc",
+ "redox_syscall",
+ "smallvec 1.10.0",
+ "winapi",
 ]
 
 [[package]]
@@ -2440,7 +2619,7 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7ff9f3fef3968a3ec5945535ed654cb38ff72d7495a25619e2247fb15a2ed9ba"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "redox_syscall",
  "smallvec 1.10.0",
@@ -2587,7 +2766,7 @@ version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8419d2b623c7c0896ff2d5d96e2cb4ede590fed28fcc34934f4c33c036e620a1"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "cpufeatures",
  "opaque-debug 0.3.0",
  "universal-hash",
@@ -2814,9 +2993,9 @@ version = "1.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4b8f95bd6966f5c87776639160a66bd8ab9895d9d4ab01ddba9fc60661aebe8d"
 dependencies = [
- "crossbeam-channel",
- "crossbeam-deque",
- "crossbeam-utils",
+ "crossbeam-channel 0.5.6",
+ "crossbeam-deque 0.8.2",
+ "crossbeam-utils 0.8.14",
  "num_cpus",
 ]
 
@@ -2953,7 +3132,7 @@ dependencies = [
  "tokio",
  "tokio-native-tls",
  "tokio-rustls",
- "tokio-util",
+ "tokio-util 0.7.2",
  "tower-service",
  "url",
  "wasm-bindgen",
@@ -3018,7 +3197,7 @@ dependencies = [
  "memchr",
  "multer",
  "num_cpus",
- "parking_lot",
+ "parking_lot 0.12.1",
  "pin-project-lite",
  "rand 0.8.5",
  "ref-cast",
@@ -3031,7 +3210,7 @@ dependencies = [
  "time 0.3.17",
  "tokio",
  "tokio-stream",
- "tokio-util",
+ "tokio-util 0.7.2",
  "ubyte",
  "version_check",
  "yansi",
@@ -3115,7 +3294,7 @@ version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2288c66aeafe3b2ed227c981f364f9968fa952ef0b30e84ada4486e7ee24d00a"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "proc-macro2",
  "quote",
  "rustc_version 0.4.0",
@@ -3230,7 +3409,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "db7826789c0e25614b03e5a54a0717a86f9ff6e6e5247f92b369472869320039"
 dependencies = [
  "bitflags",
- "cfg-if",
+ "cfg-if 1.0.0",
  "clipboard-win",
  "dirs-next",
  "fd-lock",
@@ -3536,7 +3715,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4d58a1e1bf39749807d89cf2d98ac2dfa0ff1cb3faa38fbb64dd88ac8013d800"
 dependencies = [
  "block-buffer 0.9.0",
- "cfg-if",
+ "cfg-if 1.0.0",
  "cpufeatures",
  "digest 0.9.0",
  "opaque-debug 0.3.0",
@@ -3548,7 +3727,7 @@ version = "0.10.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "82e6b795fe2e3b1e845bafcb27aa35405c4d47cdfc92af5fc8d3002f76cebdc0"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "cpufeatures",
  "digest 0.10.6",
 ]
@@ -3623,7 +3802,7 @@ version = "2.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "766c59b252e62a34651412870ff55d8c4e6d04df19b43eecb2703e417b097ffe"
 dependencies = [
- "crossbeam-channel",
+ "crossbeam-channel 0.5.6",
  "slog",
  "take_mut",
  "thread_local",
@@ -3731,7 +3910,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c886bd4480155fd3ef527d45e9ac8dd7118a898a46530b7b94c3e21866259fce"
 dependencies = [
  "cc",
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "psm",
  "winapi",
@@ -3763,9 +3942,9 @@ dependencies = [
 
 [[package]]
 name = "stacks-rpc-client"
-version = "1.0.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aca7b97b09d835c932c1ee24335adcb4a85225aaf6eb566aa36fe6f9f18958cd"
+checksum = "f3160c1225d52bd81f588ad39a7382385e47018990893466b98e5420b0e56b48"
 dependencies = [
  "clarinet-utils",
  "clarity-repl",
@@ -3928,7 +4107,7 @@ version = "3.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5cdb1ef4eaeeaddc8fbd371e5017057064af0911902ef36b39801f67cc6d79e4"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "fastrand",
  "libc",
  "redox_syscall",
@@ -4100,6 +4279,15 @@ dependencies = [
  "sha2 0.8.2",
 ]
 
+[[package]]
+name = "tiny-keccak"
+version = "2.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2c9d3793400a45f954c52e73d068316d76b6f4e36977e3fcebb13a2721e80237"
+dependencies = [
+ "crunchy",
+]
+
 [[package]]
 name = "tinytemplate"
 version = "1.2.1"
@@ -4137,7 +4325,7 @@ dependencies = [
  "memchr",
  "mio",
  "num_cpus",
- "parking_lot",
+ "parking_lot 0.12.1",
  "pin-project-lite",
  "signal-hook-registry",
  "socket2",
@@ -4188,6 +4376,21 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "tokio-util"
+version = "0.6.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36943ee01a6d67977dd3f84a5a1d2efeb4ada3a1ae771cadfaa535d9d9fc6507"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "futures-io",
+ "futures-sink",
+ "log",
+ "pin-project-lite",
+ "tokio",
+]
+
 [[package]]
 name = "tokio-util"
 version = "0.7.2"
@@ -4224,7 +4427,7 @@ version = "0.1.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ce8c33a8d48bd45d624a6e523445fd21ec13d3653cd51f681abf67418f54eb8"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "pin-project-lite",
  "tracing-attributes",
  "tracing-core",
@@ -4390,6 +4593,15 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "936e4b492acfd135421d8dca4b1aa80a7bfc26e702ef3af710e0752684df5372"
 
+[[package]]
+name = "uuid"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bc5cf98d8186244414c848017f0e2676b3fcb46807f6668a97dfe67359a3c4b7"
+dependencies = [
+ "getrandom 0.2.8",
+]
+
 [[package]]
 name = "uuid"
 version = "1.3.0"
@@ -4469,7 +4681,7 @@ version = "0.2.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "eaf9f5aceeec8be17c128b2e93e031fb8a4d469bb9c4ae2d7dc1888b26887268"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "wasm-bindgen-macro",
 ]
 
@@ -4494,7 +4706,7 @@ version = "0.4.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "23639446165ca5a5de86ae1d8896b737ae80319560fbaa4c2887b7da6e7ebd7d"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "js-sys",
  "wasm-bindgen",
  "web-sys",
@@ -4761,3 +4973,29 @@ name = "zeroize"
 version = "1.5.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c394b5bd0c6f669e7275d9c20aa90ae064cb22e75a1cad54e1b34088034b149f"
+
+[[package]]
+name = "zeromq"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "667ece59294ccaf617fcf2e5decc9114a06427c1f68990028b9f12d322686bdc"
+dependencies = [
+ "async-trait",
+ "asynchronous-codec",
+ "bytes",
+ "crossbeam",
+ "dashmap",
+ "enum-primitive-derive",
+ "futures",
+ "futures-util",
+ "lazy_static",
+ "log",
+ "num-traits",
+ "parking_lot 0.11.2",
+ "rand 0.7.3",
+ "regex",
+ "thiserror",
+ "tokio",
+ "tokio-util 0.6.10",
+ "uuid 0.8.2",
+]
diff --git a/components/chainhook-event-observer/Cargo.toml b/components/chainhook-event-observer/Cargo.toml
index 25ee3fbe..ea6e9705 100644
--- a/components/chainhook-event-observer/Cargo.toml
+++ b/components/chainhook-event-observer/Cargo.toml
@@ -50,6 +50,7 @@ threadpool = "1.8.1"
 rand = "0.8.5"
 hex-simd = "0.8.0"
 serde_cbor = "0.11.2"
+zeromq = { version = "*", default-features = false, features = ["tokio-runtime", "tcp-transport"] }
 
 [replace]
 "jsonrpc:0.13.0" = { git = 'https://github.com/apoelstra/rust-jsonrpc', rev = "1063671f122a8985c1b7c29030071253da515839" }
diff --git a/components/chainhook-event-observer/src/observer/mod.rs b/components/chainhook-event-observer/src/observer/mod.rs
index 07a2bb45..cceb7332 100644
--- a/components/chainhook-event-observer/src/observer/mod.rs
+++ b/components/chainhook-event-observer/src/observer/mod.rs
@@ -409,6 +409,15 @@ pub async fn start_event_observer(
         let _ = hiro_system_kit::nestable_block_on(ignite.launch());
     });
 
+    if let BitcoinBlockSignaling::ZeroMQ(ref bitcoind_zmq_url) = config.bitcoin_block_signaling {
+        let bitcoind_zmq_endpoint = bitcoind_zmq_url.parse::<zeromq::Endpoint>()?;
+        hiro_system_kit::thread_named("Bitcoind zmq listener")
+            .spawn(move || {
+                // bitcoind_zmq_endpoint
+            })
+            .expect("unable to spawn thread");
+    }
+
     // This loop is used for handling background jobs, emitted by HTTP calls.
     start_observer_commands_handler(
         config,
@@ -1187,6 +1196,16 @@ pub async fn handle_new_bitcoin_block(
     background_job_tx: &State<Arc<Mutex<Sender<ObserverCommand>>>>,
     ctx: &State<Context>,
 ) -> Json<JsonValue> {
+    if bitcoin_config
+        .bitcoin_block_signaling
+        .should_ignore_bitcoin_block_signaling_through_stacks()
+    {
+        return Json(json!({
+            "status": 200,
+            "result": "Ok",
+        }));
+    }
+
     ctx.try_log(|logger| slog::info!(logger, "POST /new_burn_block"));
     // Standardize the structure of the block, and identify the
     // kind of update that this new block would imply, taking