diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 69eb7a4c..1a57f7c7 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -9,7 +9,7 @@ jobs:
   build:
     strategy:
       matrix:
-        rust-toolchain: ["1.83"]
+        rust-toolchain: ["1.84"]
         os: [ubuntu-24.04, macos-14, windows-2022]
         arch: [amd64, arm64]
         exclude:
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 066659bf..059ff882 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -20,7 +20,7 @@ jobs:
       with:
         submodules: true
     - name: Install Rust
-      run: rustup update --no-self-update 1.83 && rustup default 1.83
+      run: rustup update --no-self-update 1.84 && rustup default 1.84
       shell: bash
     - name: Add wasm32-wasip1 Rust target
       run: rustup target add wasm32-wasip1
@@ -89,7 +89,7 @@ jobs:
         with:
           submodules: true
       - name: Install Rust
-        run: rustup update 1.83 && rustup default 1.83
+        run: rustup update 1.84 && rustup default 1.84
         shell: bash
       - name: Check crates can be published
         run: make package-check
diff --git a/Cargo.toml b/Cargo.toml
index 731744d7..08fca238 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,7 +5,7 @@ members = [
     "crates/adapter",
     "crates/adapter/byte-array-literals",
 ]
-resolver = "2"
+resolver = "3"
 
 # Exclude our integration test fixtures, which need to be compiled to wasm
 # (managed by the Makefile)
diff --git a/cli/Cargo.toml b/cli/Cargo.toml
index ad2b766d..b2f5108b 100644
--- a/cli/Cargo.toml
+++ b/cli/Cargo.toml
@@ -26,6 +26,7 @@ include = [
 ]
 # MSRV: 1.78 for wasm32-wasip1
 rust-version = "1.78"
+resolver = "3"
 
 [[bin]]
 name = "viceroy"
diff --git a/cli/tests/trap-test/Cargo.toml b/cli/tests/trap-test/Cargo.toml
index c4ebef70..02c829f7 100644
--- a/cli/tests/trap-test/Cargo.toml
+++ b/cli/tests/trap-test/Cargo.toml
@@ -6,6 +6,7 @@ authors = []
 edition = "2021"
 license = "Apache-2.0 WITH LLVM-exception"
 publish = false
+resolver="3"
 
 [dependencies]
 anyhow = "1.0.31"
diff --git a/crates/adapter/Cargo.toml b/crates/adapter/Cargo.toml
index 4c5866b1..810019cc 100644
--- a/crates/adapter/Cargo.toml
+++ b/crates/adapter/Cargo.toml
@@ -3,6 +3,7 @@ name = "viceroy-component-adapter"
 version = "0.0.0"
 edition = "2021"
 publish = false
+resolver = "3"
 
 [dependencies]
 wasi = { workspace = true }
diff --git a/crates/adapter/byte-array-literals/Cargo.toml b/crates/adapter/byte-array-literals/Cargo.toml
index 6f27edb0..aaeb0a03 100644
--- a/crates/adapter/byte-array-literals/Cargo.toml
+++ b/crates/adapter/byte-array-literals/Cargo.toml
@@ -2,6 +2,7 @@
 name = "byte-array-literals"
 version = "0.0.0"
 publish = false
+resolver = "3"
 
 [lib]
 proc-macro = true
diff --git a/lib/Cargo.toml b/lib/Cargo.toml
index bbe730d9..7ec95e74 100644
--- a/lib/Cargo.toml
+++ b/lib/Cargo.toml
@@ -25,6 +25,7 @@ include = [
 ]
 # MSRV: 1.82 for is_none_or
 rust-version = "1.82"
+resolver = "3"
 
 [dependencies]
 anyhow = { workspace = true }
diff --git a/rust-toolchain b/rust-toolchain
index 74c280fb..40671b90 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-1.83
+1.84
diff --git a/test-fixtures/Cargo.toml b/test-fixtures/Cargo.toml
index 582fa596..0dd10cf0 100644
--- a/test-fixtures/Cargo.toml
+++ b/test-fixtures/Cargo.toml
@@ -6,6 +6,7 @@ authors = ["Fastly"]
 edition = "2021"
 license = "Apache-2.0 WITH LLVM-exception"
 publish = false
+resolver = "3"
 
 [dependencies]
 anyhow = "1.0.86"