diff --git a/pkgs/by-name/gi/gildas/package.nix b/pkgs/by-name/gi/gildas/package.nix
index 6370487384b4..e9ecdf646aea 100644
--- a/pkgs/by-name/gi/gildas/package.nix
+++ b/pkgs/by-name/gi/gildas/package.nix
@@ -37,7 +37,7 @@ stdenv.mkDerivation rec {
       "http://www.iram.fr/~gildas/dist/gildas-src-${srcVersion}.tar.xz"
       "http://www.iram.fr/~gildas/dist/archive/gildas/gildas-src-${srcVersion}.tar.xz"
     ];
-    sha256 = "sha256-5XKImlE5A6JjA6LLqmGc4IzaMMPoHDo8cUPmgRtnEp0=";
+    hash = "sha256-5XKImlE5A6JjA6LLqmGc4IzaMMPoHDo8cUPmgRtnEp0=";
   };
 
   nativeBuildInputs = [
@@ -97,6 +97,8 @@ stdenv.mkDerivation rec {
     done
   '';
 
+  passthru.updateScript = ./update.py;
+
   meta = {
     description = "Radioastronomy data analysis software";
     longDescription = ''
diff --git a/pkgs/by-name/gi/gildas/update.py b/pkgs/by-name/gi/gildas/update.py
new file mode 100755
index 000000000000..19e0d09294b1
--- /dev/null
+++ b/pkgs/by-name/gi/gildas/update.py
@@ -0,0 +1,145 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i python3 -p "python3.withPackages (ps: [ ps.beautifulsoup4 ps.requests ])"
+
+"""
+Update the gildas package in nixpkgs.
+
+"""
+
+import re
+import subprocess
+import requests
+import os
+from bs4 import BeautifulSoup
+
+
+def to_version(srcVersion):
+    """
+    Convert the source version to the package version
+
+    This function converts the source version from the format "apr25a"
+    to "20250401_a".
+
+    """
+
+    months = {
+        "jan": "01",
+        "feb": "02",
+        "mar": "03",
+        "apr": "04",
+        "may": "05",
+        "jun": "06",
+        "jul": "07",
+        "aug": "08",
+        "sep": "09",
+        "oct": "10",
+        "nov": "11",
+        "dec": "12",
+    }
+
+    month = srcVersion[0:3]
+    year = srcVersion[3:5]
+    revision = srcVersion[5:6]
+
+    return f"20{year}{months[month]}01_{revision}"
+
+
+def get_srcVersion():
+    """
+    Get the available source versions from the gildas website
+
+    """
+
+    srcVersions = []
+    response = requests.get("https://www.iram.fr/~gildas/dist/index.html")
+    soup = BeautifulSoup(response.text, "html.parser")
+    pattern = r"^gildas-src-([a-z]{3}\d{2}[a-z])\.tar\.xz$"
+    for link in soup.find_all("a"):
+        href = link["href"]
+        match = re.search(pattern, href)
+        if match:
+            srcVersions.append(match.group(1))
+
+    return srcVersions
+
+
+def find_latest(srcVersions):
+    """
+    Return the latest source version from a list
+
+    """
+
+    latestVersion = ""
+    for srcVersion in srcVersions:
+        version = to_version(srcVersion)
+        if version > latestVersion:
+            latest = srcVersion
+
+    return latest
+
+
+def get_hash(srcVersion):
+    """
+    Get the hash of a given source versionn
+
+    """
+
+    url = f"http://www.iram.fr/~gildas/dist/gildas-src-{srcVersion}.tar.xz"
+    srcHash = (
+        subprocess.check_output(["nix-prefetch-url", url, "--unpack"]).decode().strip()
+    )
+
+    return f"sha256:{srcHash}"
+
+
+def get_package_attribute(attr):
+    """
+    Get a package attribute
+
+    """
+
+    pattern = attr + r'\s*=\s*"([^"]+)";'
+    with open("package.nix", "r") as f:
+        for line in f:
+            match = re.search(pattern, line)
+            if match:
+                return match.group(1)
+
+
+def update_package(srcVersion, version, srcHash):
+    """
+    Update the package
+
+    """
+
+    current_srcVersion = get_package_attribute("srcVersion")
+    current_version = get_package_attribute("version")
+    current_hash = get_package_attribute("hash")
+
+    with open("package.nix", "r") as f:
+        lines = f.readlines()
+
+    with open("package.nix", "w") as f:
+        for line in lines:
+            line = line.replace(current_srcVersion, srcVersion)
+            line = line.replace(current_version, version)
+            line = line.replace(current_hash, srcHash)
+            f.write(line)
+
+
+def main():
+    os.chdir(os.path.dirname(os.path.abspath(__file__)))  # allow to run from anywhere
+    latest = find_latest(get_srcVersion())
+    if latest != get_package_attribute("srcVersion"):
+        srcVersion = latest
+        version = to_version(srcVersion)
+        print(f"Updating gildas to {version}...")
+        srcHash = get_hash(srcVersion)
+        update_package(srcVersion, version, srcHash)
+        print("done")
+    else:
+        print("Already up to date")
+
+
+if __name__ == "__main__":
+    main()