diff --git a/dev/opentitan.nix b/dev/opentitan.nix
index 72118be2..2c48a5f2 100644
--- a/dev/opentitan.nix
+++ b/dev/opentitan.nix
@@ -5,8 +5,8 @@
   pkgs,
   ncurses5-fhs,
   ncurses6-fhs,
-  bazel_ot,
-  python_ot,
+  bazelisk,
+  python-ot,
   verilator_ot,
   verible_ot,
   edaTools ? [],
@@ -18,7 +18,7 @@
   ...
 }: let
   # These dependencies are required for building user DPI C/C++ code, and cosimulation models.
-  edaExtraDeps = with pkgs; [elfutils openssl python_ot];
+  edaExtraDeps = with pkgs; [elfutils openssl python-ot];
 
   gcc-patched = wrapCCWith {
     cc = gcc-unwrapped;
@@ -46,13 +46,13 @@ in
     targetPkgs = _:
       with pkgs;
         [
-          bazel_ot
+          bazelisk
           verilator_ot
           verible_ot
 
           # Python dependencies
           uv
-          python_ot
+          python-ot
 
           # For serde-annotate which can be built with just cargo
           rustup
diff --git a/flake.nix b/flake.nix
index 6906e4ee..a6857081 100644
--- a/flake.nix
+++ b/flake.nix
@@ -56,7 +56,7 @@
           })
         ];
       };
-      lowrisc_pkgs = import ./pkgs {inherit pkgs inputs;};
+      lowriscPkgs = import ./pkgs {inherit pkgs inputs;};
     in {
       checks = {
         license = pkgs.stdenv.mkDerivation {
@@ -73,15 +73,15 @@
           '';
         };
       };
-      packages = flake-utils.lib.filterPackages system lowrisc_pkgs;
+      packages = flake-utils.lib.filterPackages system lowriscPkgs;
       devShells = {
         opentitan = pkgs.callPackage ./dev/opentitan.nix {
-          inherit (lowrisc_pkgs) ncurses5-fhs ncurses6-fhs bazel_ot verilator_ot python_ot verible_ot;
+          inherit (lowriscPkgs) ncurses5-fhs ncurses6-fhs bazelisk verilator_ot python-ot verible_ot;
         };
         cheriot = pkgs.mkShell {
           name = "cheriot";
           packages =
-            (with lowrisc_pkgs; [llvm_cheriot xmake])
+            (with lowriscPkgs; [llvm-cheriot xmake])
             ++ (with pkgs; [
               gnumake
               magic-enum
@@ -89,7 +89,7 @@
             ]);
         };
         caliptra = pkgs.callPackage ./dev/caliptra.nix {
-          inherit (lowrisc_pkgs) verilator_caliptra riscv64-gcc_caliptra;
+          inherit (lowriscPkgs) verilator_caliptra riscv64-gcc_caliptra;
         };
       };
       formatter = pkgs.alejandra;
diff --git a/pkgs/bazel_ot/default.nix b/pkgs/bazelisk/default.nix
similarity index 100%
rename from pkgs/bazel_ot/default.nix
rename to pkgs/bazelisk/default.nix
diff --git a/pkgs/default.nix b/pkgs/default.nix
index b051e16c..7042b51a 100644
--- a/pkgs/default.nix
+++ b/pkgs/default.nix
@@ -12,13 +12,13 @@
 
   # OpenTitan packages
   verilator_ot = import ./verilator {inherit pkgs;};
-  python_ot = pkgs.callPackage ./python_ot {inherit inputs;};
-  bazel_ot = pkgs.callPackage ./bazel_ot {};
+  python-ot = pkgs.callPackage ./python-ot {inherit inputs;};
+  bazelisk = pkgs.callPackage ./bazelisk {};
   verible_ot = pkgs.callPackage ./verible.nix {};
 
   # CherIoT packages
   spike-ibex-cosim = pkgs.callPackage ./spike.nix {};
-  llvm_cheriot = pkgs.callPackage ./llvm_cheriot.nix {};
+  llvm-cheriot = pkgs.callPackage ./llvm-cheriot.nix {};
   xmake = pkgs.callPackage ./xmake {};
   cheriot-sim = pkgs.callPackage ./cheriot-sim.nix {};
   cheriot-audit = pkgs.callPackage ./cheriot-audit.nix {};
diff --git a/pkgs/llvm_cheriot.nix b/pkgs/llvm-cheriot.nix
similarity index 87%
rename from pkgs/llvm_cheriot.nix
rename to pkgs/llvm-cheriot.nix
index 781e6889..54fd1c01 100644
--- a/pkgs/llvm_cheriot.nix
+++ b/pkgs/llvm-cheriot.nix
@@ -13,12 +13,12 @@
 }:
 stdenv.mkDerivation rec {
   pname = "llvm-cheriot";
-  version = "17.0.0";
+  version = "19.0.0";
   src = fetchFromGitHub {
     owner = "CHERIoT-Platform";
     repo = "llvm-project";
-    rev = "905c7f67bda89433c7787903d61342bb25f85a42";
-    hash = "sha256-Md9QXylYvo7SYowZ89PkDLvZ6SjtWjnOThduzlDsJe0=";
+    rev = "d94219e399453f5e4f584809b6c898ce7b9fd5b0";
+    hash = "sha256-9LQOHLRMtJimgMfv0ZMEDz7/2ruuisGxBbNgn/iC39Q=";
   };
   sourceRoot = "${src.name}/llvm";
   nativeBuildInputs = [cmake ninja lld python3] ++ lib.optional stdenv.isDarwin darwin.apple_sdk.libs.xpc;
diff --git a/pkgs/python_ot/default.nix b/pkgs/python-ot/default.nix
similarity index 100%
rename from pkgs/python_ot/default.nix
rename to pkgs/python-ot/default.nix
diff --git a/pkgs/python_ot/pyproject.toml b/pkgs/python-ot/pyproject.toml
similarity index 100%
rename from pkgs/python_ot/pyproject.toml
rename to pkgs/python-ot/pyproject.toml
diff --git a/pkgs/python_ot/uv.lock b/pkgs/python-ot/uv.lock
similarity index 100%
rename from pkgs/python_ot/uv.lock
rename to pkgs/python-ot/uv.lock