diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 949617e79..f12a27ea4 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -29,7 +29,7 @@ jobs:
 
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: "1.64" # MSRV
+          toolchain: "1.65" # MSRV
           override: true
 
       - uses: actions-rs/cargo@v1.0.3
@@ -98,7 +98,7 @@ jobs:
 
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: "1.64" # MSRV
+          toolchain: "1.65" # MSRV
           override: true
 
       - uses: actions-rs/cargo@v1.0.3
diff --git a/.github/workflows/rust-tests.yml b/.github/workflows/rust-tests.yml
index 440debee1..d7eb0b748 100644
--- a/.github/workflows/rust-tests.yml
+++ b/.github/workflows/rust-tests.yml
@@ -15,7 +15,7 @@ jobs:
     strategy:
       matrix:
         rust:
-          - "1.64" # MSRV
+          - "1.65" # MSRV
           - "stable"
         os:
           - ubuntu-latest
diff --git a/Cargo.lock b/Cargo.lock
index cdac3c76d..a26e12cbb 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1241,9 +1241,9 @@ dependencies = [
 
 [[package]]
 name = "proptest"
-version = "1.3.1"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7c003ac8c77cb07bb74f5f198bce836a689bcd5a42574612bf14d17bfd08c20e"
+checksum = "31b476131c3c86cb68032fdc5cb6d5a1045e3e42d96b69fa599fd77701e1f5bf"
 dependencies = [
  "bit-set",
  "bit-vec",
@@ -1253,7 +1253,7 @@ dependencies = [
  "rand",
  "rand_chacha",
  "rand_xorshift",
- "regex-syntax",
+ "regex-syntax 0.8.2",
  "rusty-fork",
  "tempfile",
  "unarray",
@@ -1340,7 +1340,7 @@ dependencies = [
  "aho-corasick",
  "memchr",
  "regex-automata",
- "regex-syntax",
+ "regex-syntax 0.7.5",
 ]
 
 [[package]]
@@ -1351,7 +1351,7 @@ checksum = "59b23e92ee4318893fa3fe3e6fb365258efbfe6ac6ab30f090cdcbb7aa37efa9"
 dependencies = [
  "aho-corasick",
  "memchr",
- "regex-syntax",
+ "regex-syntax 0.7.5",
 ]
 
 [[package]]
@@ -1360,6 +1360,12 @@ version = "0.7.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dbb5fb1acd8a1a18b3dd5be62d25485eb770e05afb408a9627d14d451bae12da"
 
+[[package]]
+name = "regex-syntax"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
+
 [[package]]
 name = "ring"
 version = "0.16.20"
diff --git a/Cargo.toml b/Cargo.toml
index 889e46d24..3d713632e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -29,7 +29,7 @@ lazy_static = "1"
 libc = "0.2.136"
 log = "^0.4.17"
 pretty_assertions = "1"
-proptest = "^1.3.1"
+proptest = "^1.4.0"
 ring = "0.16"
 rstest = "0.17"
 rusqlite = { version = "0.29", features = ["bundled"] }
diff --git a/taskchampion/taskchampion/src/lib.rs b/taskchampion/taskchampion/src/lib.rs
index 680b637ec..9682747bb 100644
--- a/taskchampion/taskchampion/src/lib.rs
+++ b/taskchampion/taskchampion/src/lib.rs
@@ -41,7 +41,7 @@ for more information about the design and usage of the tool.
 
 # Minimum Supported Rust Version (MSRV)
 
-This crate supports Rust version 1.64 and higher.
+This crate supports Rust version 1.65 and higher.
 
  */