diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 000000000..eb5a316cb
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1 @@
+target
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 78d5c74ee..c99fae36a 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -15,25 +15,25 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Cache cargo registry
-        uses: actions/cache@v4
-        with:
-          path: ~/.cargo/registry
-          key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
-
-      - name: Cache cargo build
-        uses: actions/cache@v4
-        with:
-          path: target
-          key: ${{ runner.os }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
-
-      - uses: actions-rs/toolchain@v1
+      - uses: dtolnay/rust-toolchain@master
+        id: toolchain
         with:
           # If this version is old enough to cause errors, or older than the
           # TaskChampion MSRV, bump it to the MSRV of the currently-required
           # TaskChampion package; if necessary, bump that version as well.
           toolchain: "1.81.0" # MSRV
-          override: true
+
+      - name: Cache cargo registry
+        uses: actions/cache@v4
+        with:
+          path: ~/.cargo/registry
+          key: ${{ runner.os }}-cargo-registry-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
+
+      - name: Cache cargo build
+        uses: actions/cache@v4
+        with:
+          path: target
+          key: ${{ runner.os }}-cargo-build-target-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - uses: actions-rs/cargo@v1.0.3
         with:
@@ -53,12 +53,11 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: actions-rs/toolchain@v1
+      - uses: dtolnay/rust-toolchain@master
+        id: toolchain
         with:
-          profile: minimal
-          components: rustfmt
-          toolchain: stable
-          override: true
+          toolchain: "stable"
+          components: "rustfmt"
 
       - uses: actions-rs/cargo@v1.0.3
         with:
@@ -71,12 +70,11 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: actions-rs/toolchain@v1
+      - uses: dtolnay/rust-toolchain@master
+        id: toolchain
         with:
-          profile: minimal
-          components: rustfmt
-          toolchain: stable
-          override: true
+          toolchain: "stable"
+          components: "rustfmt"
 
       - name: "Check metadata"
         run: ".github/workflows/metadata-check.sh"
diff --git a/.github/workflows/release-check.yaml b/.github/workflows/release-check.yaml
index 8138356a7..57cfa0dc7 100644
--- a/.github/workflows/release-check.yaml
+++ b/.github/workflows/release-check.yaml
@@ -6,16 +6,14 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      - uses: dtolnay/rust-toolchain@stable
+        id: toolchain
+
       - name: Cache cargo registry
         uses: actions/cache@v4
         with:
           path: ~/.cargo/registry
-          key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
-
-      - uses: actions-rs/toolchain@v1
-        with:
-          toolchain: "stable"
-          override: true
+          key: ${{ runner.os }}-cargo-registry-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Install uuid-dev
         run: sudo apt install uuid-dev
diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
index 78c6b74dc..bdc3347ee 100644
--- a/.github/workflows/tests.yaml
+++ b/.github/workflows/tests.yaml
@@ -43,22 +43,20 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      - uses: dtolnay/rust-toolchain@stable
+        id: toolchain
+
       - name: Cache cargo registry
         uses: actions/cache@v4
         with:
           path: ~/.cargo/registry
-          key: ${{ runner.os }}-stable-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+          key: ${{ runner.os }}-cargo-registry-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Cache cargo build
         uses: actions/cache@v4
         with:
           path: target
-          key: ${{ runner.os }}-stable-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
-
-      - uses: actions-rs/toolchain@v1
-        with:
-          toolchain: "stable"
-          override: true
+          key: ${{ runner.os }}-cargo-build-target-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Test MacOS
         run: bash test/scripts/test_macos.sh
@@ -72,22 +70,20 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      - uses: dtolnay/rust-toolchain@stable
+        id: toolchain
+
       - name: Cache cargo registry
         uses: actions/cache@v4
         with:
           path: ~/.cargo/registry
-          key: ${{ runner.os }}-stable-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+          key: ${{ runner.os }}-cargo-registry-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Cache cargo build
         uses: actions/cache@v4
         with:
           path: target
-          key: ${{ runner.os }}-stable-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
-
-      - uses: actions-rs/toolchain@v1
-        with:
-          toolchain: "stable"
-          override: true
+          key: ${{ runner.os }}-cargo-build-target-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Test MacOS
         run: bash test/scripts/test_macos.sh
@@ -101,26 +97,25 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      - uses: dtolnay/rust-toolchain@master
+        id: toolchain
+        with:
+          # If this version is old enough to cause errors, or older than the
+          # TaskChampion MSRV, bump it to the MSRV of the currently-required
+          # TaskChampion package; if necessary, bump that version as well.
+          toolchain: "1.81.0" # MSRV
+
       - name: Cache cargo registry
         uses: actions/cache@v4
         with:
           path: ~/.cargo/registry
-          key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+          key: ${{ runner.os }}-cargo-registry-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Cache cargo build
         uses: actions/cache@v4
         with:
           path: target
-          key: ${{ runner.os }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
-
-      - uses: actions-rs/toolchain@v1
-        with:
-          # If this version is old enough to cause errors, or older than the
-          # TaskChampion MSRV, bump it to the MSRV of the currently-required
-          # TaskChampion package; if necessary, bump that version as well.
-          # This should match the MSRV in `src/taskchampion-cpp/Cargo.toml`.
-          toolchain: "1.81.0" # MSRV
-          override: true
+          key: ${{ runner.os }}-cargo-build-target-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('**/Cargo.lock') }}
 
       - uses: actions-rs/cargo@v1.0.3
         with:
diff --git a/src/taskchampion-cpp/corrosion b/src/taskchampion-cpp/corrosion
index 64289b1d7..fcd8b4198 160000
--- a/src/taskchampion-cpp/corrosion
+++ b/src/taskchampion-cpp/corrosion
@@ -1 +1 @@
-Subproject commit 64289b1d79d6d19cd2e241db515381a086bb8407
+Subproject commit fcd8b41981cb1e80f4dcc20fa8970dc6aa981c9f