chore: pin the toolchain and declare an MSRV that is true

.github/workflows/ci.yml

@@ -10,9 +10,26 @@ on:
   pull_request:
 
 env:
+  # PINNED, not `stable`. On 2026-07-29 the runner moved to clippy 1.97, which
+  # added `question_mark`, and the lint gate went red with no commit behind it —
+  # a compiler release is not a change to this repository and must not be able
+  # to fail its CI.
+  #
+  # Pinning here rather than in a `rust-toolchain.toml`: the toolchain action
+  # exports RUSTUP_TOOLCHAIN, which takes precedence over that file, so the
+  # pin would be ignored in exactly the place it is needed. The file exists too,
+  # for local parity.
+  #
+  # To bump: raise this, run `cargo +<new> clippy --workspace --all-targets --
+  # -D warnings` and `cargo +<new> fmt --all -- --check` locally first, and fix
+  # whatever the new release added in the same commit.
+  RUST_VERSION: "1.97.0"
   CARGO_TERM_COLOR: always
   RUST_BACKTRACE: 1
-  MSRV: "1.85"
+  # The version this project promises to build on, verified by the job below
+  # against the WHOLE workspace. Keep in step with `rust-version` in the root
+  # Cargo.toml, which is where consumers read it.
+  MSRV: "1.91"
 
 jobs:
   # MSRV (Minimum Supported Rust Version) check
@@ -43,8 +60,11 @@ jobs:
           restore-keys: |
             ${{ runner.os }}-cargo-msrv-
 
+      # `-p aingle_minimal` before, which is the one member with no wasmer in
+      # its dependency tree — so it passed at 1.85 while the workspace could
+      # not build below 1.91. A promise nothing checks is not a promise.
       - name: Check MSRV
-        run: cargo check -p aingle_minimal
+        run: cargo check --workspace --all-targets
 
   # Format check
   fmt:
@@ -54,8 +74,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
         with:
+          toolchain: ${{ env.RUST_VERSION }}
           components: rustfmt
 
       - name: Check formatting
@@ -69,8 +90,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
         with:
+          toolchain: ${{ env.RUST_VERSION }}
           components: clippy
 
       - name: Install system dependencies
@@ -118,7 +140,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |
@@ -151,7 +175,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |
@@ -183,7 +209,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |
@@ -227,7 +255,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install cargo-audit
         run: cargo install cargo-audit
@@ -245,8 +275,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
         with:
+          toolchain: ${{ env.RUST_VERSION }}
           components: llvm-tools-preview
 
       - name: Install system dependencies
@@ -288,7 +319,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |
@@ -327,7 +360,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |
@@ -356,7 +391,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |

.github/workflows/docs.yml

@@ -15,6 +15,8 @@ concurrency:
   cancel-in-progress: true
 
 env:
+  # Pinned on purpose: see the note in ci.yml.
+  RUST_VERSION: "1.97.0"
   CARGO_TERM_COLOR: always
 
 jobs:
@@ -25,7 +27,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |

.github/workflows/release.yml

@@ -15,6 +15,8 @@ permissions:
   contents: write
 
 env:
+  # Pinned on purpose: see the note in ci.yml.
+  RUST_VERSION: "1.97.0"
   CARGO_TERM_COLOR: always
 
 jobs:
@@ -50,8 +52,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
         with:
+          toolchain: ${{ env.RUST_VERSION }}
           targets: ${{ matrix.target }}
 
       - name: Install system dependencies (Linux)
@@ -163,7 +166,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install system dependencies
         run: |

.github/workflows/security.yml

@@ -17,6 +17,8 @@ on:
   workflow_dispatch:
 
 env:
+  # Pinned on purpose: see the note in ci.yml.
+  RUST_VERSION: "1.97.0"
   CARGO_TERM_COLOR: always
 
 jobs:
@@ -28,7 +30,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install cargo-audit
         run: cargo install cargo-audit
@@ -60,7 +64,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install cargo-deny
         run: cargo install cargo-deny
@@ -109,7 +115,9 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_VERSION }}
 
       - name: Install cargo-vet
         run: cargo install cargo-vet

Cargo.toml

@@ -1,3 +1,17 @@
+[workspace.package]
+# The MSRV, declared ONCE. It said 1.83 in twelve crates, 1.85 in the CI
+# environment and 1.83 in CLAUDE.md, and the truth was none of those: the
+# workspace needs 1.91, because `wasmer` (via aingle_contracts) requires it
+# and `cranelift` under it requires 1.90. Verified by bisection — 1.85 and
+# 1.90 both fail, 1.91 builds. Nothing had ever checked, because the MSRV job
+# ran `cargo check -p aingle_minimal`: the one member with no wasmer in its
+# tree.
+#
+# Uniform rather than per-crate on purpose: a lower number on a crate that
+# has not been built at that version is the same unverified promise this is
+# replacing. Refine per crate only with a run behind each figure.
+rust-version = "1.91"
+
 [workspace]
 resolver = "2"
 members = [

crates/aingle_ai/Cargo.toml

@@ -10,8 +10,7 @@ authors = ["Apilium Technologies <hello@apilium.com>"]
 keywords = ["aingle", "ai", "titans", "nested-learning", "memory"]
 categories = ["science", "algorithms"]
 edition = "2021"
-rust-version = "1.83"
-
+rust-version.workspace = true
 [dependencies]
 # Serialization
 serde = { version = "1", features = ["derive"] }

crates/aingle_ai/src/nested_learning/mod.rs

@@ -93,7 +93,10 @@ impl NestedLearning {
         self.tx_count += 1;
 
         // 4. Check if optimizer-level update is needed
-        if self.tx_count % self.config.optimizer_update_interval == 0 {
+        if self
+            .tx_count
+            .is_multiple_of(self.config.optimizer_update_interval)
+        {
             debug!(
                 tx_count = self.tx_count,
                 "Triggering optimizer-level update"
@@ -114,7 +117,10 @@ impl NestedLearning {
         self.block_count += 1;
 
         // Check if meta-level update is needed
-        if self.block_count % self.config.meta_update_interval == 0 {
+        if self
+            .block_count
+            .is_multiple_of(self.config.meta_update_interval)
+        {
             debug!(
                 block_count = self.block_count,
                 "Triggering meta-level update"

crates/aingle_contracts/Cargo.toml

@@ -10,8 +10,7 @@ authors = ["Apilium Technologies <hello@apilium.com>"]
 keywords = ["aingle", "smart-contracts", "wasm", "dsl", "blockchain"]
 categories = ["wasm", "database"]
 edition = "2021"
-rust-version = "1.83"
-
+rust-version.workspace = true
 [features]
 default = ["runtime"]
 runtime = ["dep:wasmer"]

crates/aingle_cortex/Cargo.toml

@@ -10,8 +10,7 @@ authors = ["Apilium Technologies <hello@apilium.com>"]
 keywords = ["aingle", "api", "graphql", "sparql", "rest"]
 categories = ["web-programming", "database"]
 edition = "2021"
-rust-version = "1.83"
-
+rust-version.workspace = true
 [features]
 default = ["rest", "sparql", "auth", "dag"]
 rest = []

crates/aingle_cortex/src/service/validate.rs

@@ -262,7 +262,7 @@ mod tests {
         let s = v
             .as_str()
             .unwrap_or_else(|| panic!("expected hex, got {v}"));
-        assert!(s.len() % 2 == 0, "hex must be byte-aligned: {s:?}");
+        assert!(s.len().is_multiple_of(2), "hex must be byte-aligned: {s:?}");
         (0..s.len() / 2)
             .map(|i| u8::from_str_radix(&s[i * 2..i * 2 + 2], 16).expect("hex digit"))
             .collect()

crates/aingle_graph/Cargo.toml

@@ -10,8 +10,7 @@ authors = ["Apilium Technologies <hello@apilium.com>"]
 keywords = ["aingle", "graph", "rdf", "semantic", "triplestore"]
 categories = ["database", "data-structures"]
 edition = "2021"
-rust-version = "1.83"
-
+rust-version.workspace = true
 [features]
 default = ["sled-backend"]
 # Storage backends

crates/aingle_ingest/Cargo.toml

@@ -4,8 +4,7 @@ version = "0.8.0"
 description = "Structural extraction of triples and text chunks from markdown/code for AIngle"
 license = "Apache-2.0 OR LicenseRef-Commercial"
 edition = "2021"
-rust-version = "1.83"
-
+rust-version.workspace = true
 [dependencies]
 aingle_graph = { version = "0.8", path = "../aingle_graph", features = ["dag"] }
 serde = { version = "1.0", features = ["derive"] }

crates/aingle_logic/Cargo.toml

@@ -10,8 +10,7 @@ authors = ["Apilium Technologies <hello@apilium.com>"]
 keywords = ["aingle", "logic", "reasoning", "validation", "rules"]
 categories = ["algorithms", "data-structures"]
 edition = "2021"
-rust-version = "1.83"
-
+rust-version.workspace = true
 [features]
 default = []
 # Enable SPARQL-like query rules

crates/aingle_minimal/Cargo.toml

@@ -10,8 +10,7 @@ authors = ["Apilium Technologies <hello@apilium.com>"]
 keywords = ["aingle", "iot", "dag", "embedded"]
 categories = ["embedded", "network-programming"]
 edition = "2021"
-rust-version = "1.85"
-
+rust-version.workspace = true
 [features]
 default = ["std", "coap", "sqlite"]
 std = []

crates/aingle_minimal/src/node.rs

@@ -569,7 +569,7 @@ impl MinimalNode {
         while self.running.load(Ordering::SeqCst) {
             // Sync discovered peers periodically (every 100 iterations = ~1 second)
             discovery_sync_counter = discovery_sync_counter.wrapping_add(1);
-            if discovery_sync_counter % 100 == 0 {
+            if discovery_sync_counter.is_multiple_of(100) {
                 self.network.sync_discovered_peers();
             }
 

crates/aingle_minimal/src/ota.rs

@@ -558,7 +558,7 @@ mod hex {
     }
 
     pub fn decode(s: &str) -> Result<Vec<u8>, String> {
-        if s.len() % 2 != 0 {
+        if !s.len().is_multiple_of(2) {
             return Err("Invalid hex string length".to_string());
         }
 

crates/aingle_minimal/src/types.rs

@@ -732,7 +732,7 @@ mod hex {
     }
 
     pub fn decode(s: &str) -> Result<Vec<u8>, FromHexError> {
-        if s.len() % 2 != 0 {
+        if !s.len().is_multiple_of(2) {
             return Err(FromHexError::OddLength);
         }
         (0..s.len())