diff --git a/Cargo.lock b/Cargo.lock
index ef25833..d9de212 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -41,9 +41,9 @@ checksum = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
 
 [[package]]
 name = "az"
-version = "0.3.1"
+version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "41a6b78289a33e09b00818ca8c90ab17c5dabb6e74f4b29a6de679c0e0886ade"
+checksum = "e9bcd47d94aa4eb8c076b50fc61a75020789394ffb9bd74a180b3379130f6569"
 
 [[package]]
 name = "base64"
@@ -384,9 +384,9 @@ dependencies = [
 
 [[package]]
 name = "gmp-mpfr-sys"
-version = "1.2.2"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "63d7f805cf9df081683d463f62864bda8b8e3ce7162a8e11cd0c49f27b8ce89b"
+checksum = "ad4e8e85ec9fb902b4564deeb17b1a263d3ba1334bef56154418aa045b159508"
 dependencies = [
  "libc",
  "winapi 0.3.8",
@@ -766,15 +766,6 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "77af24da69f9d9341038eba93a073b1fdaaa1b788221b00a69bce9e762cb32de"
 
-[[package]]
-name = "openssl-src"
-version = "111.9.0+1.1.1g"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a2dbe10ddd1eb335aba3780eb2eaa13e1b7b441d2562fd962398740927f39ec4"
-dependencies = [
- "cc",
-]
-
 [[package]]
 name = "openssl-sys"
 version = "0.9.58"
@@ -784,7 +775,6 @@ dependencies = [
  "autocfg 1.0.0",
  "cc",
  "libc",
- "openssl-src",
  "pkg-config",
  "vcpkg",
 ]
@@ -1159,9 +1149,9 @@ dependencies = [
 
 [[package]]
 name = "rug"
-version = "1.8.0"
+version = "1.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "72315b6d9cb7d886fb99724330c47ceb29e923df657c31da3849fe88c0ded710"
+checksum = "e538d00da450a8e48aac7e6322e67b2dc86ec71a1feeac0e3954c4f07f01bc45"
 dependencies = [
  "az",
  "gmp-mpfr-sys",
@@ -1232,7 +1222,7 @@ checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 
 [[package]]
 name = "scryer-prolog"
-version = "0.8.126"
+version = "0.8.127"
 dependencies = [
  "base64 0.12.3",
  "blake2",
@@ -1243,6 +1233,7 @@ dependencies = [
  "divrem",
  "downcast",
  "git-version",
+ "gmp-mpfr-sys",
  "hostname",
  "indexmap",
  "lazy_static",
diff --git a/Cargo.toml b/Cargo.toml
index c359e1b..75c4325 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -41,10 +41,14 @@ ring = "0.16.13"
 ripemd160 = "0.8.0"
 sha3 = "0.8.2"
 blake2 = "0.8.1"
-openssl = { version = "0.10.29", features = ["vendored"] }
+openssl = { version = "0.10.29" }
 native-tls = "0.2.4"
 chrono = "0.4.11"
 select = "0.4.3"
 roxmltree = "0.11.0"
 base64 = "0.12.3"
 sodiumoxide = "0.2.6"
+
+[dependencies.gmp-mpfr-sys]
+version = "1.4"
+features = ["use-system-libs"]