diff --git a/CHANGELOG b/CHANGELOG
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,12 @@
 # Changelog
 
+- 0.3.6 (2026-10-31)
+  * Bumps the ppad-fixed and ppad-secp256k1 dependencies, to 0.2.1
+    and 0.5.9, which under the llvm flag on x86_64 are compiled with
+    LLVM's x86 cmov converter off (-optlc=-x86-cmov-converter=false).
+    This library is compiled likewise, as ppad-fixed's constant-time
+    arithmetic can be inlined into it.
+
 - 0.3.5 (2026-08-01)
   * Merely bumps the ppad-fixed and ppad-secp256k1 dependencies.
 
diff --git a/ppad-bip32.cabal b/ppad-bip32.cabal
--- a/ppad-bip32.cabal
+++ b/ppad-bip32.cabal
@@ -1,6 +1,6 @@
 cabal-version:      3.0
 name:               ppad-bip32
-version:            0.3.5
+version:            0.3.6
 synopsis:           BIP32 hierarchical deterministic wallets.
 license:            MIT
 license-file:       LICENSE
@@ -31,15 +31,21 @@
       -Wall
   if flag(llvm)
     ghc-options: -fllvm -O2
+  -- LLVM's x86 backend rewrites a cmov whose operand is a load as a
+  -- branch (its cmov converter), which would make the borrow-masked
+  -- correction of ppad-fixed's sub_mod# (inlinable here) a branch on
+  -- the borrow; keep the cmov.
+  if flag(llvm) && arch(x86_64)
+    ghc-options: -optlc=-x86-cmov-converter=false
   exposed-modules:
       Crypto.HDKey.BIP32
   build-depends:
       base >= 4.9 && < 5
     , bytestring >= 0.9 && < 0.13
     , ppad-base58 >= 0.2.3 && < 0.3
-    , ppad-fixed >= 0.2 && < 0.3
+    , ppad-fixed >= 0.2.1 && < 0.3
     , ppad-ripemd160 >= 0.1.4 && < 0.2
-    , ppad-secp256k1 >= 0.5.8 && < 0.6
+    , ppad-secp256k1 >= 0.5.9 && < 0.6
     , ppad-sha256 >= 0.3.2 && < 0.4
     , ppad-sha512 >= 0.2.2 && < 0.3