diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index dce3f340..6a385e6e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -23,7 +23,7 @@ jobs:
           #{ id: 'linux-aarch64', os: ['self-hosted', 'aarch64'], rust-target: 'aarch64-unknown-linux-gnu', rust-toolchain: 'stable' },
         ]
         # The job runs on different Python versions.
-        python: [3.5, 3.6, 3.7, 3.8, 3.9]
+        python: [3.5, 3.6, 3.7, 3.8, 3.9, pypy3]
       # As soon as one job fails in the matrix, all the other
       # in-progress jobs are canceled.
       fail-fast: false
@@ -46,19 +46,19 @@ jobs:
         uses: actions/cache@v1
         with:
           path: ~/.cargo/registry
-          key: ${{ matrix.target.rust-target }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+          key: ${{ matrix.target.id }}-${{ matrix.python }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Cache Cargo bin
         uses: actions/cache@v1
         with:
           path: ~/.cargo/bin
-          key: ${{ matrix.target.rust-target }}-cargo-bin-${{ hashFiles('**/Cargo.lock') }}
+          key: ${{ matrix.target.id }}-${{ matrix.python }}-cargo-bin-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Cache Cargo build
         uses: actions/cache@v1
         with:
           path: target
-          key: ${{ matrix.target.rust-target }}-${{ matrix.python }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
+          key: ${{ matrix.target.id }}-${{ matrix.python }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Set up Python ${{ matrix.python }}
         if: matrix.target.id != 'linux-aarch64'
@@ -77,7 +77,7 @@ jobs:
         uses: actions/cache@v1
         with:
           path: ~/.pyenv/versions/
-          key: ${{ matrix.target.rust-target }}-pyenv-version-${{ matrix.python }}
+          key: ${{ matrix.target.id }}-${{ matrix.python }}-pyenv-version
 
       - name: Set up Python ${{ matrix.python }}
         if: matrix.target.id == 'linux-aarch64'
diff --git a/Cargo.lock b/Cargo.lock
index d2df78f1..6a6693f5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,11 +2,11 @@
 # It is not intended for manual editing.
 [[package]]
 name = "addr2line"
-version = "0.13.0"
+version = "0.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1b6a2d3371669ab3ca9797670853d61402b03d0b4b9ebf33d677dfa720203072"
+checksum = "7c0929d69e78dd9bf5408269919fcbcaeb2e35e5d43e5815517cdc6a8e11a423"
 dependencies = [
- "gimli 0.22.0",
+ "gimli 0.23.0",
 ]
 
 [[package]]
@@ -26,9 +26,9 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.33"
+version = "1.0.34"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a1fd36ffbb1fb7c834eac128ea8d0e310c5aeb635548f9d58861e1308d46e71c"
+checksum = "bf8dcb5b4bbaa28653b647d8c77bd4ed40183b48882e130c1f1ffb73de069fd7"
 
 [[package]]
 name = "autocfg"
@@ -38,15 +38,15 @@ checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
 
 [[package]]
 name = "backtrace"
-version = "0.3.53"
+version = "0.3.54"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "707b586e0e2f247cbde68cdd2c3ce69ea7b7be43e1c5b426e37c9319c4b9838e"
+checksum = "2baad346b2d4e94a24347adeee9c7a93f412ee94b9cc26e5b59dea23848e9f28"
 dependencies = [
  "addr2line",
  "cfg-if 1.0.0",
  "libc",
  "miniz_oxide",
- "object 0.21.1",
+ "object 0.22.0",
  "rustc-demangle",
 ]
 
@@ -101,9 +101,9 @@ dependencies = [
 
 [[package]]
 name = "const_fn"
-version = "0.4.2"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce90df4c658c62f12d78f7508cf92f9173e5184a539c10bfe54a3107b3ffd0f2"
+checksum = "c478836e029dcef17fb47c89023448c64f781a046e0300e257ad8225ae59afab"
 
 [[package]]
 name = "cranelift-bforest"
@@ -392,9 +392,9 @@ dependencies = [
 
 [[package]]
 name = "gimli"
-version = "0.22.0"
+version = "0.23.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aaf91faf136cb47367fa430cd46e37a788775e7fa104f8b4bcb3861dc389b724"
+checksum = "f6503fe142514ca4799d4c26297c4248239fe8838d827db6bd6065c6ed29a6ce"
 
 [[package]]
 name = "goblin"
@@ -668,9 +668,9 @@ dependencies = [
 
 [[package]]
 name = "object"
-version = "0.21.1"
+version = "0.22.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37fd5004feb2ce328a52b0b3d01dbf4ffff72583493900ed15f22d4111c51693"
+checksum = "8d3b63360ec3cb337817c2dbd47ab4a0f170d285d8e5a2064600f3def1402397"
 
 [[package]]
 name = "once_cell"
@@ -737,9 +737,9 @@ checksum = "b4596b6d070b27117e987119b4dac604f3c58cfb0b191112e24771b2faeac1a6"
 
 [[package]]
 name = "ppv-lite86"
-version = "0.2.9"
+version = "0.2.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c36fa947111f5c62a733b652544dd0016a43ce89619538a8ef92724a6f501a20"
+checksum = "ac74c624d6b2d21f425f752262f42188365d7b8ff1aff74c82e45136510a4857"
 
 [[package]]
 name = "proc-macro-error"
@@ -923,9 +923,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.4.1"
+version = "1.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8963b85b8ce3074fecffde43b4b0dded83ce2f367dc8d363afc56679f3ee820b"
+checksum = "38cf2c13ed4745de91a5eb834e11c00bcc3709e773173b2ce4c56c9fbde04b9c"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -935,9 +935,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.20"
+version = "0.6.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8cab7a364d15cde1e505267766a2d3c4e22a843e1a601f0fa7564c0f82ced11c"
+checksum = "3b181ba2dcf07aaccad5448e8ead58db5b742cf85dfe035e2227f137a539a189"
 
 [[package]]
 name = "region"