diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f23208b..52fccc1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -29,7 +29,7 @@ jobs:
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
           # Keep in sync with rust-toolchain.toml.
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
           components: rustfmt, clippy
       - name: Cache cargo
         # Tag runs re-verify a release: keep them off restored build state.
@@ -89,7 +89,7 @@ jobs:
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
           # Keep in sync with rust-toolchain.toml.
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
           components: clippy
       - name: Cache cargo
         # Tag runs re-verify a release: keep them off restored build state.
@@ -265,7 +265,7 @@ jobs:
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
           # Keep in sync with rust-toolchain.toml.
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
       - name: Cache cargo
         if: ${{ !startsWith(github.ref, 'refs/tags/') }}
         uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6  # v2.9.2
diff --git a/.github/workflows/mutants.yml b/.github/workflows/mutants.yml
index 0628c6c..0a784c0 100644
--- a/.github/workflows/mutants.yml
+++ b/.github/workflows/mutants.yml
@@ -98,7 +98,7 @@ jobs:
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
           # Keep in sync with rust-toolchain.toml.
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
       - name: Install cargo-mutants
         # Exact version and --locked, as release.yml installs cargo-deb and
         # cargo-generate-rpm. A crates.io version is immutable and --locked
diff --git a/.github/workflows/perf.yml b/.github/workflows/perf.yml
index 2334c8e..85603ee 100644
--- a/.github/workflows/perf.yml
+++ b/.github/workflows/perf.yml
@@ -31,7 +31,7 @@ jobs:
       - name: Install Rust toolchain
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
       - name: Cache cargo
         uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6  # v2.9.2
         with:
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 75c518a..9214e2b 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -36,7 +36,7 @@ jobs:
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
           # Keep in sync with rust-toolchain.toml.
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
       # No cargo cache here: releases are built hermetically so restored
       # build state can never influence published artifacts.
 
@@ -115,7 +115,7 @@ jobs:
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
           # Keep in sync with rust-toolchain.toml.
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
       # No cargo cache, same hermetic-release rule as `build` above.
 
       - name: Verify tag matches workspace version
@@ -715,7 +715,7 @@ jobs:
         uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c  # master
         with:
           # Keep in sync with rust-toolchain.toml.
-          toolchain: "1.98.1"
+          toolchain: "1.99.1"
 
       - name: Authenticate to crates.io
         uses: rust-lang/crates-io-auth-action@c6f97d42243bad5fab37ca0427f495c86d5b1a18  # v1.0.5
diff --git a/AGENTS.md b/AGENTS.md
index 680598c..97e3a6d 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -20,7 +20,7 @@ cargo deny check
 ```
 
 Use the toolchain pinned in `rust-toolchain.toml` (repo root, currently
-`1.98.1`). That pin, the `toolchain:` inputs in `.github/workflows/`, and
+`1.99.1`). That pin, the `toolchain:` inputs in `.github/workflows/`, and
 the `FROM rust:` tag in the `Dockerfile` all name the same version and move
 together; `rust-msrv` (the MSRV) and `rust-beta` (`beta`) are the deliberate
 exceptions. An input only installs that toolchain and sets the rustup
diff --git a/Dockerfile b/Dockerfile
index e7bb6ff..3324c1b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -4,7 +4,7 @@
 # so a floating `rust:1` would silently build releases with an unpinned
 # compiler. Bump this tag and rust-toolchain.toml together; the
 # toolchain-drift job fails when they disagree.
-FROM rust:1.98.1-alpine@sha256:7cc1c22d77d9432f7fe012a70e6d3e555af54c2a6832700ed7d553f1769ae89f AS build
+FROM rust:1.99.1-alpine@sha256:7e9e2d068a107a2adafd19930011178d14a78326053cd4c3a9f7ad3fd049557d AS build
 # gcc and musl-dev are already in the base; aws-lc-sys (the rustls crypto
 # provider) compiles C from source and needs cmake plus a make generator.
 RUN apk add --no-cache cmake make
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index b18872f..abb28e8 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -4,5 +4,5 @@
 # toolchain-drift job compares against this channel; the workspace MSRV
 # (rust-version in Cargo.toml) is a separate, lower bound.
 [toolchain]
-channel = "1.98.1"
+channel = "1.99.1"
 components = ["rustfmt", "clippy"]