diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..d7af31b
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,26 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    name: cargo test (workspace)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@1.88.0
+        with:
+          components: rustfmt, clippy
+      - uses: Swatinem/rust-cache@v2
+      - name: Format check
+        run: cargo fmt --all -- --check
+      - name: Clippy
+        run: cargo clippy --locked --workspace --all-targets -- -D warnings
+      - name: Tests
+        run: cargo test --locked --workspace
diff --git a/Cargo.toml b/Cargo.toml
index 3696a88..9dee78e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,7 +5,7 @@ members = ["crates/coven-threads-core"]
 [workspace.package]
 version = "0.2.0"
 edition = "2021"
-rust-version = "1.75"
+rust-version = "1.88"
 license = "MIT"
 authors = ["Valentina Alexander <val@opencoven.dev>"]
 repository = "https://github.com/OpenCoven/coven-threads"
diff --git a/crates/coven-threads-core/src/audit.rs b/crates/coven-threads-core/src/audit.rs
index 82b9dcc..a9572d8 100644
--- a/crates/coven-threads-core/src/audit.rs
+++ b/crates/coven-threads-core/src/audit.rs
@@ -634,7 +634,7 @@ fn validate_proposal_approval_detail(
                 || detail
                     .rationale
                     .as_deref()
-                    .map_or(true, |rationale| rationale.trim().is_empty())
+                    .is_none_or(|rationale| rationale.trim().is_empty())
             {
                 return Err("human_required approval requires an approver and rationale".into());
             }
diff --git a/crates/coven-threads-core/src/identity_invariants.rs b/crates/coven-threads-core/src/identity_invariants.rs
index 6af8e0e..f99d888 100644
--- a/crates/coven-threads-core/src/identity_invariants.rs
+++ b/crates/coven-threads-core/src/identity_invariants.rs
@@ -241,8 +241,7 @@ impl IdentityInvariantSet {
         for mandatory in [IdentityFact::Name, IdentityFact::Person] {
             if !seen.contains(&mandatory) {
                 return Err(format!(
-                    "missing mandatory {:?} identity invariant declaration",
-                    mandatory
+                    "missing mandatory {mandatory:?} identity invariant declaration"
                 ));
             }
         }
diff --git a/docs/STATUS-2026-07-15.md b/docs/STATUS-2026-07-15.md
index edbe205..3e04a1a 100644
--- a/docs/STATUS-2026-07-15.md
+++ b/docs/STATUS-2026-07-15.md
@@ -68,7 +68,7 @@ Dependency spine: Phase 2 epic (986.14) was blocked by Phase 1 work and permissi
 
 ## 5. Phase 1 + Phase 2 crate side — landed
 
-- Root `Cargo.toml` — workspace (resolver 2, edition 2021, MSRV 1.75; deps: serde, serde_json, thiserror, uuid, blake3, time; `unsafe_code = "forbid"`, `missing_docs = "warn"`).
+- Root `Cargo.toml` — workspace (resolver 2, edition 2021, MSRV 1.88; deps: serde, serde_json, thiserror, uuid, blake3, time; `unsafe_code = "forbid"`, `missing_docs = "warn"`).
 - `crates/coven-threads-core/` (`86550d8`) — `ids`, `strand`, `thread`, `channel`, `fray`, `pattern`, `weave`, `manifest`, `validate` (§5 receiver), plus `tests/rfc0001_s5_conformance.rs` (465 lines).
 - Phase 2 crate side (`5e68957`) — `audit.rs` (`ward.audit` contract, 285 lines) + `staging.rs` (DegradeToProposal records, 206 lines).