diff --git a/gnu/local.mk b/gnu/local.mk
index c7db93ecd6..8b6ebc51f4 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1215,6 +1215,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/dvdbackup-with-libdvdread-6.1.0+.patch	\
   %D%/packages/patches/dvd+rw-tools-add-include.patch 		\
   %D%/packages/patches/dwarves-threading-reproducibility.patch	\
+  %D%/packages/patches/e9patch-zydis-4.1-compat.patch		\
   %D%/packages/patches/efitools-riscv64-support.patch		\
   %D%/packages/patches/efivar-fix-fprint-format.patch		\
   %D%/packages/patches/elastix-1404.patch			\
diff --git a/gnu/packages/patches/e9patch-zydis-4.1-compat.patch b/gnu/packages/patches/e9patch-zydis-4.1-compat.patch
new file mode 100644
index 0000000000..93621b687e
--- /dev/null
+++ b/gnu/packages/patches/e9patch-zydis-4.1-compat.patch
@@ -0,0 +1,80 @@
+commit c02dd23b12fd687a041ab3b872b3f989cd1342dc
+Author: Nguyễn Gia Phong <cnx@loang.net>
+Date:   2024-11-18 15:13:17 +0900
+
+    Make compatible with Zydis 4.1
+
+    This Zydis version is more explicit in formatting
+    lea instructions in Intel format.
+
+    The hunk adding sqrtss is due to a bug in Zydis:
+    https://github.com/zyantific/zydis/issues/542
+
+    For this reason, E9Patch is not open to updating Zydis.
+
+diff --git a/src/e9tool/e9x86_64.cpp b/src/e9tool/e9x86_64.cpp
+index 6a7f5cff3692..03eb3a41dd66 100644
+--- a/src/e9tool/e9x86_64.cpp
++++ b/src/e9tool/e9x86_64.cpp
+@@ -152,8 +152,7 @@ void e9tool::getInstrInfo(const ELF *elf, const Instr *I, InstrInfo *info,
+     ZydisDecodedOperand operands[ZYDIS_MAX_OPERAND_COUNT];
+ 
+     ZyanStatus result = ZydisDecoderDecodeFull(&decoder,
+-        elf->data + I->offset, I->size, D, operands, ZYDIS_MAX_OPERAND_COUNT,
+-        0);
++        elf->data + I->offset, I->size, D, operands);
+     if (!ZYAN_SUCCESS(result) || I->size != D->length ||
+             D->operand_count > sizeof(info->op) / sizeof(info->op[0]))
+         error("failed to decompress instruction at address 0x%lx; decode "
+@@ -336,7 +335,7 @@ void e9tool::getInstrInfo(const ELF *elf, const Instr *I, InstrInfo *info,
+         info->string.section    = elf->strs + shdr->sh_name;
+         result = ZydisFormatterFormatInstruction(&formatter, D, operands,
+             D->operand_count_visible, info->string.instr,
+-            sizeof(info->string.instr)-1, I->address);
++            sizeof(info->string.instr)-1, I->address, ZYAN_NULL);
+         if (!ZYAN_SUCCESS(result))
+             error("failed to decompress instruction at address 0x%lx; "
+                 "formatting failed", I->address);
+diff --git a/test/regtest/print_intel.exp b/test/regtest/print_intel.exp
+index ae91f44..9bdbe0f 100644
+--- a/test/regtest/print_intel.exp
++++ b/test/regtest/print_intel.exp
+@@ -24,14 +24,14 @@ jmp 0xa000163
+ call 0xa000168
+ jmp 0xa00016d
+ jmp 0xa000177
+-lea r10, [rip+0x14]
++lea r10, qword ptr [rip+0x14]
+ push r10
+ push r11
+ mov rcx, 0xffffffffffff8889
+ jmp qword ptr [rsp+rcx*1+0x777f]
+ call 0xa0001b5
+ add rsp, 0x8
+-lea rdx, [rip+0x2]
++lea rdx, qword ptr [rip+0x2]
+ call rdx
+ pop r14
+ add r9, 0x6
+@@ -85,7 +85,7 @@ xor eax, eax
+ inc eax
+ mov edi, eax
+ inc rdi
+-lea rsi, [rip+0x54]
++lea rsi, qword ptr [rip+0x54]
+ mov rdx, 0x7
+ syscall
+ PASSED
+diff --git a/test/regtest/same_op_2.exp b/test/regtest/same_op_2.exp
+index f99033a..45790b8 100644
+--- a/test/regtest/same_op_2.exp
++++ b/test/regtest/same_op_2.exp
+@@ -12,6 +12,7 @@ shl $0x7, %rdi
+ sar $0x3, %rdi
+ pxor %xmm0, %xmm0
+ cvtsi2ss %rax, %xmm0
++sqrtss %xmm0, %xmm1
+ xor %esi, %esi
+ xor %eax, %eax
+ PASSED
+
diff --git a/gnu/packages/patchutils.scm b/gnu/packages/patchutils.scm
index 52979779f9..b980359edc 100644
--- a/gnu/packages/patchutils.scm
+++ b/gnu/packages/patchutils.scm
@@ -34,6 +34,8 @@
   #:use-module (gnu packages compression)
   #:use-module (gnu packages databases)
   #:use-module (gnu packages django)
+  #:use-module (gnu packages elf)
+  #:use-module (gnu packages engineering)
   #:use-module (gnu packages file)
   #:use-module (gnu packages freedesktop)
   #:use-module (gnu packages gawk)
@@ -44,6 +46,7 @@
   #:use-module (gnu packages gtk)
   #:use-module (gnu packages less)
   #:use-module (gnu packages mail)
+  #:use-module (gnu packages markup)
   #:use-module (gnu packages ncurses)
   #:use-module (gnu packages ocaml)
   #:use-module (gnu packages package-management)
@@ -56,6 +59,7 @@
   #:use-module (gnu packages text-editors)
   #:use-module (gnu packages time)
   #:use-module (gnu packages version-control)
+  #:use-module (gnu packages vim)
   #:use-module (gnu packages xml)
   #:use-module (gnu packages)
   #:use-module (guix build-system glib-or-gtk)
@@ -121,6 +125,59 @@ using semantic patches in the @acronym{SmPL, Semantic Patch Language} for
 specifying desired matches and transformations in the C code.")
       (license license:gpl2))))
 
+(define-public e9patch
+  (package
+    (name "e9patch")
+    (version "1.0.0")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/GJDuck/e9patch")
+             (commit (string-append "v" version))))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32 "1bgv05fnz0kfzpyikadp96zrr83214lk2nx82jpmlv9dq0lhxccq"))
+       ;; E9Patch is sensitive to Zydis version, including the latter's bugs:
+       ;; https://github.com/GJDuck/e9patch/pull/94#issuecomment-2525069952
+       (patches (search-patches "e9patch-zydis-4.1-compat.patch"))
+       (modules '((guix build utils)))
+       ;; The following snippet is also for Zydis 4.1 compatibility.
+       ;; The patch replaces a single line in 43 files, producing a giant diff:
+       ;; https://github.com/GJDuck/e9patch/pull/93.patch
+       (snippet
+        #~(begin
+            (substitute* (find-files "test/regtest" "\\.exp$")
+              (("\\$0x8877665544332211")
+               "$-0x778899aabbccddef"))
+            ;; The regular expression to test is .*a.*,
+            ;; matching the number produced by the substitution above.
+            (substitute* "test/regtest/not_regex.exp"
+              ((".*\\$-0x778899aabbccddef.*")
+               ""))))))
+    (build-system gnu-build-system)
+    (arguments
+     (list
+      #:phases
+      #~(modify-phases %standard-phases
+          (delete 'configure))
+      #:make-flags
+      #~(list (string-append "CC=" #$(cc-for-target))
+              (string-append "PREFIX=" #$output))))
+    (native-inputs (list markdown xxd))
+    (inputs (list elfutils zycore zydis zlib))
+    (home-page "https://github.com/GJDuck/e9patch")
+    (synopsis "Static binary rewriting tool")
+    (description
+     "E9Patch is a static binary rewriting tool for x86-64 ELF binaries,
+both executables and shared objects.  The patched binaries can be used
+in place of the original, without requiring additional runtime dependencies.
+Binary patches can be defined through a high-level interface, which focuses
+on ease of use, or low-level interfaces, which provide additional flexibility
+and allow optimizations for performance.")
+    (license (list license:expat        ;src/e9patch/e9loader_*.cpp
+                   license:gpl3+))))    ;rest
+
 (define-public patchutils
   (package
     (name "patchutils")