diff --git a/Cargo.toml b/Cargo.toml
index a07fe043..ad5765f7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -70,9 +70,9 @@ improvise-wasm-client = { path = "crates/improvise-wasm-client" }
 improvise-protocol = { path = "crates/improvise-protocol", features = ["test-support"] }
 # `tests/headless_cli.rs` detaches the binary from any terminal with `setsid`.
 libc = "0.2"
-pest = "2.9.2"
-pest_derive = "2.9.2"
-pest_meta = "2.9.2"
+pest = "2.9.3"
+pest_derive = "2.9.3"
+pest_meta = "2.9.3"
 proptest = "1"
 tempfile = "3"
 
diff --git a/crates/improvise-core/Cargo.toml b/crates/improvise-core/Cargo.toml
index a83cf35b..ee52b099 100644
--- a/crates/improvise-core/Cargo.toml
+++ b/crates/improvise-core/Cargo.toml
@@ -17,7 +17,7 @@ serde = { version = "1", features = ["derive"] }
 # wasm-clean.
 siphasher = "1"
 # Unicode full case folding for slugify (ADR 007 answer 26). no_std, no dependencies.
-unicase = "2.9"
+unicase = "2.10"
 
 [features]
 # Exposes the fold-evaluation counter to other crates' tests (improvise-0jw5).
diff --git a/crates/improvise-formula/Cargo.toml b/crates/improvise-formula/Cargo.toml
index 00bf407c..823bd23e 100644
--- a/crates/improvise-formula/Cargo.toml
+++ b/crates/improvise-formula/Cargo.toml
@@ -8,11 +8,11 @@ repository = "https://github.com/fiddlerwoaroof/improvise"
 
 [dependencies]
 anyhow = "1"
-pest = "2.9.2"
-pest_derive = "2.9.2"
+pest = "2.9.3"
+pest_derive = "2.9.3"
 # For FormulaId alone, which crosses the wire (improvise-km71); no AST derive.
 serde = { version = "1", features = ["derive"] }
 
 [dev-dependencies]
-pest_meta = "2.9.2"
+pest_meta = "2.9.3"
 proptest = "1"
diff --git a/crates/improvise-io/Cargo.toml b/crates/improvise-io/Cargo.toml
index bb8d367f..88f544ee 100644
--- a/crates/improvise-io/Cargo.toml
+++ b/crates/improvise-io/Cargo.toml
@@ -14,8 +14,8 @@ chrono = { version = "0.4", features = ["serde"] }
 csv = "1"
 flate2 = "1"
 indexmap = "2"
-pest = "2.9.2"
-pest_derive = "2.9.2"
+pest = "2.9.3"
+pest_derive = "2.9.3"
 serde = { version = "1", features = ["derive"] }
 # Parses JSON a user's numbers cross, so it must read back the f64 written: per crate,
 # because each build stands alone (improvise-6yvg, context/code/protocol.md).
@@ -47,6 +47,6 @@ features = [
 ]
 
 [dev-dependencies]
-pest_meta = "2.9.2"
+pest_meta = "2.9.3"
 proptest = "1"
 tempfile = "3"
diff --git a/flake.nix b/flake.nix
index 278b5d65..dce8b0e9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -121,8 +121,10 @@
           pkgs.rust-analyzer
           crate2nix.packages.${system}.default
           pkgs.cargo-expand
+          pkgs.cargo-edit
           pkgs.cargo-llvm-cov
           pkgs.global
+          pkgs.iconv
           pkgs.universal-ctags
           beads.packages.${system}.default
           codeMaat