diff --git a/Cargo.toml b/Cargo.toml
index 8580cbe0275879..3b9c8b88809cd7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,7 +11,7 @@ resolver = "2"
 [workspace.package]
 # Please update rustfmt.toml when bumping the Rust edition
 edition = "2024"
-rust-version = "1.95"
+rust-version = "1.98.1"
 homepage = "https://docs.astral.sh/ruff"
 documentation = "https://docs.astral.sh/ruff"
 repository = "https://github.com/astral-sh/ruff"
diff --git a/crates/ruff_cpp_codegen/Cargo.toml b/crates/ruff_cpp_codegen/Cargo.toml
index 495cccedd10ea1..af36e1db76eb9b 100644
--- a/crates/ruff_cpp_codegen/Cargo.toml
+++ b/crates/ruff_cpp_codegen/Cargo.toml
@@ -3,7 +3,7 @@ name = "ruff_cpp_codegen"
 version = "0.1.0"
 publish = false
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.98.1"
 description = "Stage 2 of the C++→Rust AST-DLL pipeline: turns the reassembled ModelGraph method plane (from ruff_cpp_spo's harvest, via ruff_spo_triplet::reassemble) into a per-class MethodSig manifest and renders it as Rust source that targets the OGAR Core. Emit-text-only — names lance-graph-contract types as text, never compiles against lance-graph. The manifest is gated by a signature-plane round-trip against the live harvested triples (decompile == expand's signature arm), so a dropped method or mangled param fails the build."
 license = "MIT"
 
diff --git a/crates/ruff_cpp_spo/Cargo.toml b/crates/ruff_cpp_spo/Cargo.toml
index 63ef98084bc58f..73c133dbcc07f3 100644
--- a/crates/ruff_cpp_spo/Cargo.toml
+++ b/crates/ruff_cpp_spo/Cargo.toml
@@ -3,7 +3,7 @@ name = "ruff_cpp_spo"
 version = "0.1.0"
 publish = false
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.98.1"
 description = "C++ machine-plane frontend for ruff_spo_triplet. Walks a C++ corpus (Tesseract first) via libclang and fills a language-agnostic ModelGraph, which expands to the same SPO triples as the Python/Odoo and Ruby/Rails frontends. The per-TU walker (`walk_tu`, behind the `libclang` feature) is implemented and tested against real libclang, as are the corpus-tree walkers (`extract_dir`, `extract_tree`); only per-TU include-arg auto-detection (`extract`) remains. C++ source corpora stay UPSTREAM — never vendored into this repo or into tesseract-rs."
 license = "MIT"
 
diff --git a/crates/ruff_csharp_spo/Cargo.toml b/crates/ruff_csharp_spo/Cargo.toml
index b607be091b16d1..4abbeb2bf1258b 100644
--- a/crates/ruff_csharp_spo/Cargo.toml
+++ b/crates/ruff_csharp_spo/Cargo.toml
@@ -3,7 +3,7 @@ name = "ruff_csharp_spo"
 version = "0.1.0"
 publish = false
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.98.1"
 description = "C# machine-plane frontend for ruff_spo_triplet. A Roslyn (.NET) harvester under `harvester/` walks a C# corpus via Microsoft.CodeAnalysis and emits SPO `Triple` ndjson in the same shape as the Python/Odoo, Ruby/Rails, and C++/Tesseract frontends. Roslyn is .NET-only, so the parse step is an out-of-process tool (unlike ruff_cpp_spo's in-Rust libclang walk); the seam is the ndjson contract, which this Rust crate loads and validates against the closed Predicate vocabulary. C# source corpora stay UPSTREAM — never vendored."
 license = "MIT"
 
diff --git a/crates/ruff_python_dto_check/Cargo.toml b/crates/ruff_python_dto_check/Cargo.toml
index 1f8d9fcfe76be9..d0bce5aaa61368 100644
--- a/crates/ruff_python_dto_check/Cargo.toml
+++ b/crates/ruff_python_dto_check/Cargo.toml
@@ -3,7 +3,7 @@ name = "ruff_python_dto_check"
 version = "0.1.0"
 publish = false
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.98.1"
 description = "Config-driven extractor over ruff_python_parser. Harvests structured DTO/route/handler facts from a Python source tree into JSON bundles, with a preflight that proposes a config from the tree itself. Additive consumer; touches no other crate."
 license = "MIT"
 
diff --git a/crates/ruff_r2il/Cargo.toml b/crates/ruff_r2il/Cargo.toml
index c7ff5b088292fc..0daf543df103d2 100644
--- a/crates/ruff_r2il/Cargo.toml
+++ b/crates/ruff_r2il/Cargo.toml
@@ -7,7 +7,7 @@ publish = false
 # pinned by hand to satisfy BOTH sides: ruff (edition 2024, rust-version per the workspace
 # Cargo.toml, toolchain per rust-toolchain.toml) and r2sleigh (edition 2024).
 edition = "2024"
-rust-version = "1.93"
+rust-version = "1.98.1"
 description = "R2IL intake arm: a lossless ore carrier over r2sleigh's r2il/r2ssa object graph, a furnace that melts it into flat facet-addressed concern rows, and an addressed residual (slag) ledger. Ore in, named slag out — no catch-all, nothing dropped."
 
 [lib]
diff --git a/crates/ruff_ruby_spo/Cargo.toml b/crates/ruff_ruby_spo/Cargo.toml
index 01950719a22dec..3c8ffa15ff9efe 100644
--- a/crates/ruff_ruby_spo/Cargo.toml
+++ b/crates/ruff_ruby_spo/Cargo.toml
@@ -3,7 +3,7 @@ name = "ruff_ruby_spo"
 version = "0.1.0"
 publish = false
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.98.1"
 description = "SCAFFOLD: Ruby/Rails (OpenProject) frontend for ruff_spo_triplet. Walks an app/models tree and fills a language-agnostic ModelGraph, which expands to the same SPO triples as the Python/Odoo frontend. Extraction points are todo!() stubs documented with the exact Rails construct to read; the target triple shape is already locked by a passing test."
 license = "MIT"
 
diff --git a/crates/ruff_spo_address/Cargo.toml b/crates/ruff_spo_address/Cargo.toml
index 9e2fb873d20750..fb152bdb725658 100644
--- a/crates/ruff_spo_address/Cargo.toml
+++ b/crates/ruff_spo_address/Cargo.toml
@@ -3,7 +3,7 @@ name = "ruff_spo_address"
 version = "0.1.0"
 publish = false
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.98.1"
 description = "Deterministic (part_of:is_a) rank-minter — the brick between the ruff_*_spo SPO harvest and the lance-graph (part_of:is_a) GUID SoA. Given a corpus's part_of edges (has_field/has_function) and is_a edges (inherits_from/rdf:type), it assigns each node a deterministic (part_of-rank, is_a-rank) at each of 6 cascade tiers and packs them into a 16-byte facet whose bytes are layout-identical to lance_graph_contract::facet::FacetCascade (facet_classid(4 LE) | 6x(lo:hi)). hi_chain = part_of (mereology), lo_chain = is_a (taxonomy); both prefix-routable. Pure std + ruff_spo_triplet; no quantization (exact + roundtrip-lossless on a known class graph). See AST-as-(part_of:is_a)-address (lance-graph .claude/knowledge)."
 license = "MIT"
 
diff --git a/crates/ruff_spo_triplet/Cargo.toml b/crates/ruff_spo_triplet/Cargo.toml
index e9dff8e32539f7..64460df14cd06d 100644
--- a/crates/ruff_spo_triplet/Cargo.toml
+++ b/crates/ruff_spo_triplet/Cargo.toml
@@ -3,7 +3,7 @@ name = "ruff_spo_triplet"
 version = "0.1.0"
 publish = false
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.98.1"
 description = "Language-agnostic SPO (Subject-Predicate-Object) triplet expansion. Turns a neutral ModelGraph IR — entities, properties, functions, and their compute/guard/traversal edges — into deterministic NARS-weighted RDF-shape triples (ndjson). Four frontends fill the same IR and call the same expander — ruff_python_spo (Odoo), ruff_ruby_spo (OpenProject/Rails), ruff_sqlalchemy_spo (Flask-SQLAlchemy) and ruff_cpp_spo (C++/libclang) — and ruff_csharp_spo joins at the ndjson contract instead, because Roslyn is .NET-only and its parse runs out of process. The downstream SPO graph is identical regardless of source language."
 license = "MIT"