diff --git a/.travis.yml b/.travis.yml
index 3d224793d..b7fdce6fc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -61,10 +61,10 @@ matrix:
 
     # Those are run all tests
     - os: linux
-      rust: nightly-2019-05-04
+      rust: nightly-2019-08-21
       env: TARGET=x86_64-unknown-linux-gnu
     - os: osx
-      rust: nightly-2019-05-04
+      rust: nightly-2019-08-21
       env: TARGET=x86_64-apple-darwin
 
     # Run clippy and rustfmt
diff --git a/Dockerfile b/Dockerfile
index 610a00e8e..303af7269 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -15,14 +15,14 @@ RUN curl https://www.musl-libc.org/releases/musl-1.1.20.tar.gz -o musl.tar.gz \
     && cd .. \
     && rm -rf x86_64-unknown-linux-musl \
     && curl https://sh.rustup.rs -sSf | sh -s -- -y \
-    && rustup toolchain add nightly-2019-05-04 \
+    && rustup toolchain add nightly-2019-08-21 \
     && rustup target add x86_64-unknown-linux-musl \
     && mkdir /io \
     && python3 -m pip install cffi
 
 ADD . /pyo3-pack/
 
-RUN cargo +nightly-2019-05-04 install --path /pyo3-pack
+RUN cargo +nightly-2019-08-21 install --path /pyo3-pack
 
 WORKDIR /io
 
diff --git a/appveyor.yml b/appveyor.yml
index 227313141..9f6b034a9 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -11,7 +11,7 @@ environment:
   matrix:
     # For the integration test
     - TARGET: x86_64-pc-windows-msvc
-      CHANNEL: nightly-2019-05-04
+      CHANNEL: nightly-2019-08-21
       PYTHON: "C:/Python36-x64"
 
     # Publishes to pypi
@@ -30,10 +30,10 @@ install:
   - SET PATH=%PATH%;%CARGO_HOME%\bin
 
   # See https://github.com/PyO3/pyo3/blob/master/ci/appveyor/setup.ps1
-  - ps: if ($env:channel -like "nightly-2019-05-04") { .\ci\setup.ps1 }
+  - ps: if ($env:channel -like "nightly-2019-08-21") { .\ci\setup.ps1 }
 
   # From and for ring
-  - IF "%CHANNEL%" == "nightly-2019-05-04" (call "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat"  x86_amd64)
+  - IF "%CHANNEL%" == "nightly-2019-08-21" (call "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat"  x86_amd64)
 
   - echo %PATH%
   - echo %LIBPATH%
@@ -42,8 +42,8 @@ install:
 
 test_script:
   - cargo build
-  - IF "%CHANNEL%" == "nightly-2019-05-04" (python.exe -m pip install cffi)
-  - IF "%CHANNEL%" == "nightly-2019-05-04" (cargo test)
+  - IF "%CHANNEL%" == "nightly-2019-08-21" (python.exe -m pip install cffi)
+  - IF "%CHANNEL%" == "nightly-2019-08-21" (cargo test)
 
 before_deploy:
   - cargo build --release --features password-storage
diff --git a/test-dockerfile.sh b/test-dockerfile.sh
index bab56118a..e2571d3d7 100755
--- a/test-dockerfile.sh
+++ b/test-dockerfile.sh
@@ -36,7 +36,7 @@ if [[ $(python test-crates/cffi-mixed/check_installed/check_installed.py) != 'SU
   exit 1
 fi
 
-docker run --rm -e RUSTUP_TOOLCHAIN=nightly-2019-05-04 -v $(pwd)/test-crates/pyo3-pure:/io pyo3-pack build --no-sdist -i python3.6
+docker run --rm -e RUSTUP_TOOLCHAIN=nightly-2019-08-21 -v $(pwd)/test-crates/pyo3-pure:/io pyo3-pack build --no-sdist -i python3.6
 
 pip install pyo3-pure --no-index --find-links test-crates/pyo3-pure/target/wheels/
 
@@ -44,7 +44,7 @@ if [[ $(python test-crates/pyo3-pure/check_installed/check_installed.py) != 'SUC
   exit 1
 fi
 
-docker run --rm -e RUSTUP_TOOLCHAIN=nightly-2019-05-04 -v $(pwd)/test-crates/pyo3-mixed:/io pyo3-pack build --no-sdist -i python3.6
+docker run --rm -e RUSTUP_TOOLCHAIN=nightly-2019-08-21 -v $(pwd)/test-crates/pyo3-mixed:/io pyo3-pack build --no-sdist -i python3.6
 
 pip install pyo3-mixed --no-index --find-links test-crates/pyo3-mixed/target/wheels/