diff --git a/Cargo.lock b/Cargo.lock
index 93e10e3aa..c01815ac7 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1103,7 +1103,7 @@ dependencies = [
 [[package]]
 name = "ethers"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "ethers-contract",
  "ethers-core",
@@ -1117,7 +1117,7 @@ dependencies = [
 [[package]]
 name = "ethers-contract"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "ethers-contract-abigen",
  "ethers-contract-derive",
@@ -1135,7 +1135,7 @@ dependencies = [
 [[package]]
 name = "ethers-contract-abigen"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "Inflector",
  "anyhow",
@@ -1152,12 +1152,13 @@ dependencies = [
  "serde_json",
  "syn",
  "url",
+ "walkdir",
 ]
 
 [[package]]
 name = "ethers-contract-derive"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "ethers-contract-abigen",
  "ethers-core",
@@ -1171,7 +1172,7 @@ dependencies = [
 [[package]]
 name = "ethers-core"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "arrayvec 0.7.2",
  "bytes",
@@ -1199,7 +1200,7 @@ dependencies = [
 [[package]]
 name = "ethers-etherscan"
 version = "0.2.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "ethers-core",
  "reqwest",
@@ -1212,7 +1213,7 @@ dependencies = [
 [[package]]
 name = "ethers-middleware"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "async-trait",
  "ethers-contract",
@@ -1235,7 +1236,7 @@ dependencies = [
 [[package]]
 name = "ethers-providers"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "async-trait",
  "auto_impl",
@@ -1265,7 +1266,7 @@ dependencies = [
 [[package]]
 name = "ethers-signers"
 version = "0.6.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "async-trait",
  "coins-bip32",
@@ -1287,7 +1288,7 @@ dependencies = [
 [[package]]
 name = "ethers-solc"
 version = "0.1.0"
-source = "git+https://github.com/gakonst/ethers-rs#568d9c8697bf6ba4944543a21c9456c0c11f0caf"
+source = "git+https://github.com/gakonst/ethers-rs#674d9aab5410e2bcdd4bb6e5b918ad56d7d954c8"
 dependencies = [
  "colored",
  "dunce",
@@ -3729,9 +3730,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "1.0.82"
+version = "1.0.84"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8daf5dd0bb60cbd4137b1b587d2fc0ae729bc07cf01cd70b36a1ed5ade3b9d59"
+checksum = "ecb2e6da8ee5eb9a61068762a32fa9619cc591ceb055b3687f4cd4051ec2e06b"
 dependencies = [
  "proc-macro2",
  "quote",
diff --git a/cli/src/cmd/build.rs b/cli/src/cmd/build.rs
index 6fba9e9a8..81e47ec4c 100644
--- a/cli/src/cmd/build.rs
+++ b/cli/src/cmd/build.rs
@@ -10,6 +10,7 @@ use ethers::{
     types::Address,
 };
 use std::{
+    collections::BTreeMap,
     path::{Path, PathBuf},
     str::FromStr,
 };
@@ -77,6 +78,9 @@ pub struct BuildArgs {
         alias = "hh"
     )]
     pub hardhat: bool,
+
+    #[structopt(help = "add linked libraries", long)]
+    pub libraries: Vec<String>,
 }
 
 impl Cmd for BuildArgs {
@@ -217,9 +221,23 @@ impl BuildArgs {
         let optimizer =
             Optimizer { enabled: Some(self.optimize), runs: Some(self.optimize_runs as usize) };
 
+        // unflatten the libraries
+        let mut libraries = BTreeMap::default();
+        for l in self.libraries.iter() {
+            let mut items = l.split(':');
+            let file = String::from(items.next().expect("could not parse libraries"));
+            let lib = String::from(items.next().expect("could not parse libraries"));
+            let addr = String::from(items.next().expect("could not parse libraries"));
+            libraries.entry(file).or_insert_with(BTreeMap::default).insert(lib, addr);
+        }
+
         // build the project w/ allowed paths = root and all the libs
-        let solc_settings =
-            Settings { optimizer, evm_version: Some(self.evm_version), ..Default::default() };
+        let solc_settings = Settings {
+            optimizer,
+            evm_version: Some(self.evm_version),
+            libraries,
+            ..Default::default()
+        };
         let mut builder = Project::builder()
             .paths(paths)
             .allowed_path(&root)