diff --git a/Cargo.lock b/Cargo.lock
index 9168b8d..e0fe8a1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -78,6 +78,14 @@ dependencies = [
  "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "cloudabi"
+version = "0.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "coco"
 version = "0.1.1"
@@ -193,7 +201,7 @@ name = "dwmapi-sys"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -266,7 +274,7 @@ name = "gdi32-sys"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -539,7 +547,7 @@ dependencies = [
  "fps_counter 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "piston_window 0.75.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "quickcheck 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -819,6 +827,23 @@ dependencies = [
  "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "rand"
+version = "0.5.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fuchsia-zircon 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "rayon"
 version = "0.8.2"
@@ -956,7 +981,7 @@ name = "shell32-sys"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1072,7 +1097,7 @@ name = "user32-sys"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1258,6 +1283,7 @@ dependencies = [
 "checksum byteorder 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ff81738b726f5d099632ceaffe7fb65b90212e8dce59d518729e7e8634032d3d"
 "checksum cfg-if 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d4c819a1287eb618df47cc647173c5c4c66ba19d888a6e50d605672aed3140de"
 "checksum cgl 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "86765cb42c2a2c497e142af72517c1b4d7ae5bb2f25dfa77a5c69642f2342d89"
+"checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
 "checksum coco 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c06169f5beb7e31c7c67ebf5540b8b472d23e3eade3b2ec7d1f5b504a85f91bd"
 "checksum cocoa 0.9.2 (registry+https://github.com/rust-lang/crates.io-index)" = "4047fed6536f40cc2ae5e7834fb38e382c788270191c4cd69196f89686d076ce"
 "checksum color_quant 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a475fc4af42d83d28adf72968d9bcfaf035a1a9381642d8e85d8a04957767b0d"
@@ -1344,6 +1370,8 @@ dependencies = [
 "checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"
 "checksum rand 0.3.22 (registry+https://github.com/rust-lang/crates.io-index)" = "15a732abf9d20f0ad8eeb6f909bf6868722d9a06e1e50802b6a70351f40b4eb1"
 "checksum rand 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "eba5f8cb59cc50ed56be8880a5c7b496bfd9bd26394e176bc67884094145c2c5"
+"checksum rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)" = "e464cd887e869cddcae8792a4ee31d23c7edd516700695608f5b98c67ee0131c"
+"checksum rand_core 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "edecf0f94da5551fc9b492093e30b041a891657db7940ee221f9d2f66e82eef2"
 "checksum rayon 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)" = "b614fe08b6665cb9a231d07ac1364b0ef3cb3698f1239ee0c4c3a88a524f54c8"
 "checksum rayon-core 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e64b609139d83da75902f88fd6c01820046840a18471e4dfcd5ac7c0f46bea53"
 "checksum read_color 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9f4c8858baa4ad3c8bcc156ae91a0ffe22b76a3975c40c49b4f04c15c6bce0da"
diff --git a/Cargo.toml b/Cargo.toml
index fb52cc6..1752173 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -33,7 +33,7 @@ display-fps = ["fps_counter"]
 [dependencies]
 find_folder = "0.3"
 piston_window = "0.75"
-rand = "0.4"
+rand = "0.5"
 
 # Optional dependencies.
 fps_counter = { version = "1.0", optional = true }