diff --git a/alire.toml b/alire.toml
index 81deb0d6a..7cee2636d 100644
--- a/alire.toml
+++ b/alire.toml
@@ -94,3 +94,26 @@ commit = "f607a63b714f09bbf6126de9851cbc21cf8666c9"
 [pins.toml_slicer]
 url    = "https://github.com/mosteo/toml_slicer"
 branch = "alire"
+
+# To disable version updating, export ALR_VERSION_DONT_PATCH with any value
+
+# Before building, we add the commit to the version, for unique identification:
+[[actions]]
+[actions.'case(os)'.windows]
+type = "pre-build"
+command = ["pwsh", "scripts/version-patcher.ps1"]
+
+[actions.'case(os)'.'...']
+type = "pre-build"
+command = ["scripts/version-patcher.sh"]
+
+# Afterwards we leave an extra note, so people manually building don't use a
+# misleading commit.
+[[actions]]
+[actions.'case(os)'.windows]
+type = "post-build"
+command = ["pwsh", "scripts/version-patcher.ps1", "_or_later"]
+
+[actions.'case(os)'.'...']
+type = "post-build"
+command = ["scripts/version-patcher.sh", "_or_later"]
\ No newline at end of file
diff --git a/dev/build.sh b/dev/build.sh
index 79e79e15d..934986401 100755
--- a/dev/build.sh
+++ b/dev/build.sh
@@ -1,12 +1,16 @@
 #!/usr/bin/env bash
 
 # Import reusable bits
-pushd $( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd ) > /dev/null
+pushd "$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )" > /dev/null || exit 1
     . functions.sh
-popd > /dev/null
+popd > /dev/null || exit 1
 
 ALIRE_BUILD_JOBS="${ALIRE_BUILD_JOBS:-0}"
-export ALIRE_OS=$(get_OS)
+ALIRE_OS=$(get_OS); export ALIRE_OS
+
+scripts/version-patcher.sh
 
 echo "Building with ALIRE_OS=$ALIRE_OS..."
-gprbuild "-j$ALIRE_BUILD_JOBS" -r -p -P `dirname $0`/../alr_env.gpr "$@"
+gprbuild "-j$ALIRE_BUILD_JOBS" -r -p -P "$(dirname $0)/../alr_env.gpr" "$@"
+
+scripts/version-patcher.sh _or_later
\ No newline at end of file
diff --git a/scripts/ci-github.sh b/scripts/ci-github.sh
index 400905ab4..845cd96d0 100755
--- a/scripts/ci-github.sh
+++ b/scripts/ci-github.sh
@@ -9,10 +9,19 @@ set -o nounset
 export PATH+=:${PWD}/bin
 
 # Import reusable bits
-pushd $( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+pushd "$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
     . ../dev/functions.sh
 popd
 
+# Mark location safe to assuage git if necessary (happens in some distros)
+if git status 2>&1 | grep -q "dubious ownership"; then
+    echo "Marking $PWD as safe for git"
+    git config --global --add safe.directory "$PWD"
+fi
+
+# Patch version
+scripts/version-patcher.sh
+
 # Build alr
 export ALIRE_OS=$(get_OS)
 gprbuild -j0 -p -P alr_env
@@ -37,7 +46,7 @@ echo ............................
 
 # Set up index if not default:
 if [ "${INDEX:-}" != "" ]; then
-    echo Setting default index to: $INDEX
+    echo Setting default index to: "$INDEX"
     alr index --name default --add "$INDEX"
 fi
 
@@ -65,8 +74,8 @@ fi
 
 echo PYTHON installing testsuite dependencies...
 
-echo Python version: $($run_python --version)
-echo Pip version: $($run_pip --version)
+echo "Python version: $($run_python --version)"
+echo "Pip version: $($run_pip --version)"
 
 $run_pip install --upgrade -r requirements.txt
 echo Python search paths:
diff --git a/scripts/version-patcher.ps1 b/scripts/version-patcher.ps1
new file mode 100644
index 000000000..1d1408bae
--- /dev/null
+++ b/scripts/version-patcher.ps1
@@ -0,0 +1,25 @@
+# This script dispatches to the Ada patcher, after building it.
+
+# Set strict mode for PowerShell to exit on error
+$ErrorActionPreference = "Stop"
+
+$bin = "support/version_patcher/bin/version_patcher.exe"
+
+# If the binary is already in place, do nothing
+if (Test-Path $bin) {
+    Write-Output "Patcher already built."
+} elseif (Get-Command gprbuild -ErrorAction SilentlyContinue) {
+    Write-Output "Building patcher with gprbuild..."
+    gprbuild -P support/version_patcher/version_patcher.gpr
+} elseif (Get-Command alr -ErrorAction SilentlyContinue) {
+    Write-Output "Building patcher with alr..."
+    alr -C (Split-Path $bin) build
+} else {
+    Write-Output "WARNING: No Ada tool available to build patcher, skipping."
+    exit 0
+}
+
+& $bin @args
+
+Write-Output "Resulting version file:"
+Get-Content src/alire/alire-version.ads | Select-String "Current_Str"
diff --git a/scripts/version-patcher.py b/scripts/version-patcher.py
new file mode 100644
index 000000000..7088bb313
--- /dev/null
+++ b/scripts/version-patcher.py
@@ -0,0 +1,55 @@
+import os
+import re
+import subprocess
+import sys
+
+def replace_version(filename, build_info):
+    pattern = r'(Current : constant String := "[^+]+\+)([^"]*)(";)'
+
+    # Depending on the context in which this is run, there may be mix-ups with
+    # line terminators between the environment detected, github runner, etc...
+    # So just keep them as they are and that should always work.
+
+    with open(filename, 'rb') as file:
+        content = file.read().decode()
+
+    # The pattern captures the part between '+' and '";', replacing it with our
+    # new build information
+
+    new_content = re.sub(pattern, r'\g<1>' + build_info + r'\3', content)
+
+    # A few sanity checks and write if needed
+
+    if new_content == content:
+        if build_info in content:
+            print(f"Note: version in {filename} already up to date")
+        else:
+            print(f"WARNING: failed to update version in {filename}")
+    else:
+        # Ensure the content line terminators are not changed
+        with open(filename, 'wb') as file:
+            file.write(new_content.encode())
+
+
+# If a flag exists, skip any updating, just print a message and exit
+if "ALR_VERSION_DONT_PATCH" in os.environ:
+    print("Note: skipping version update")
+    sys.exit(0)
+
+# If there is an argument to the script, retrieve it here and use it as the new
+# dirty flag after the commit
+if len(sys.argv) > 1:
+    dirty = sys.argv[1]
+else:
+    # Detect whether the current directory contains changes
+    if subprocess.call(['git', 'diff-index', '--quiet', 'HEAD', '--']) != 0:
+        dirty = "_dirty"
+    else:
+        dirty = ""
+
+# Find the short git commit of the repository in the current directory
+commit = subprocess.check_output(['git', 'rev-parse', '--short', 'HEAD']).decode('utf-8').strip()
+
+# Replace the build version part with the short commit hash plus any extra info
+print(f"Updating version in src/alire/alire-version.ads to commit {commit}{dirty}...")
+replace_version('src/alire/alire-version.ads', commit+dirty)
diff --git a/scripts/version-patcher.sh b/scripts/version-patcher.sh
new file mode 100755
index 000000000..1b0c07895
--- /dev/null
+++ b/scripts/version-patcher.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+# This script dispatches to the Ada patcher, after building it.
+
+set -o errexit
+
+# Exit already if the ALR_VERSION_DONT_PATCH flag is defined
+if [ "${ALR_VERSION_DONT_PATCH:-unset}" != "unset" ]; then
+    echo "Skipping version patching..."
+    exit 0
+fi
+
+bin=support/version_patcher/bin/version_patcher
+
+# If the binary is already in place, do nothing
+if [ -f $bin ]; then
+    echo "Patcher already built."
+elif (which gprbuild &>/dev/null); then
+    echo "Building patcher with gprbuild..."
+    gprbuild -P support/version_patcher/version_patcher.gpr
+elif (which alr &>/dev/null); then
+    echo "Building patcher with alr..."
+    alr -C "$(dirname $bin)" build
+else
+    echo "WARNING: No Ada tool available to build patcher, skipping."
+    exit 0
+fi
+
+$bin "$@"
+
+echo "Resulting version file:"
+cat src/alire/alire-version.ads | grep Current_Str
\ No newline at end of file
diff --git a/src/alire/alire-version.ads b/src/alire/alire-version.ads
index 6a0e4f70d..441a826dc 100644
--- a/src/alire/alire-version.ads
+++ b/src/alire/alire-version.ads
@@ -12,6 +12,10 @@ private
 
    --  Remember to update Alire.Index branch if needed too
 
+   --  NOTE: in the following version string, the build part (after '+') will
+   --  be replaced by `alr build` with the current commit, and appended with
+   --  "_or_later" after build.
+
    Current_Str : constant String := "2.1-dev";
    --  2.0.0:     alr settings refactor and minor fixes
    --  2.0.0-rc1: release candidate for 2.0
diff --git a/support/version_patcher/.gitignore b/support/version_patcher/.gitignore
new file mode 100644
index 000000000..5866d7bfa
--- /dev/null
+++ b/support/version_patcher/.gitignore
@@ -0,0 +1,4 @@
+/obj/
+/bin/
+/alire/
+/config/
diff --git a/support/version_patcher/alire.toml b/support/version_patcher/alire.toml
new file mode 100644
index 000000000..22000e222
--- /dev/null
+++ b/support/version_patcher/alire.toml
@@ -0,0 +1,12 @@
+name = "version_patcher"
+description = "Patches current commit into alire-version.ads"
+version = "0.1.0-dev"
+
+authors = ["Alejandro R. Mosteo"]
+maintainers = ["Alejandro R. Mosteo <alejandro@mosteo.com>"]
+maintainers-logins = ["mosteo"]
+licenses = "MIT OR Apache-2.0 WITH LLVM-exception"
+website = ""
+tags = []
+
+executables = ["version_patcher"]
diff --git a/support/version_patcher/config/version_patcher_config.ads b/support/version_patcher/config/version_patcher_config.ads
new file mode 100644
index 000000000..440dfe5a6
--- /dev/null
+++ b/support/version_patcher/config/version_patcher_config.ads
@@ -0,0 +1,20 @@
+--  Configuration for version_patcher generated by Alire
+pragma Restrictions (No_Elaboration_Code);
+pragma Style_Checks (Off);
+
+package Version_Patcher_Config is
+   pragma Pure;
+
+   Crate_Version : constant String := "0.1.0-dev";
+   Crate_Name : constant String := "version_patcher";
+
+   Alire_Host_OS : constant String := "linux";
+
+   Alire_Host_Arch : constant String := "x86_64";
+
+   Alire_Host_Distro : constant String := "ubuntu";
+
+   type Build_Profile_Kind is (release, validation, development);
+   Build_Profile : constant Build_Profile_Kind := development;
+
+end Version_Patcher_Config;
diff --git a/support/version_patcher/config/version_patcher_config.gpr b/support/version_patcher/config/version_patcher_config.gpr
new file mode 100644
index 000000000..df412e7cb
--- /dev/null
+++ b/support/version_patcher/config/version_patcher_config.gpr
@@ -0,0 +1,50 @@
+--  Configuration for version_patcher generated by Alire
+abstract project Version_Patcher_Config is
+   Crate_Version := "0.1.0-dev";
+   Crate_Name := "version_patcher";
+
+   Alire_Host_OS := "linux";
+
+   Alire_Host_Arch := "x86_64";
+
+   Alire_Host_Distro := "ubuntu";
+   Ada_Compiler_Switches := External_As_List ("ADAFLAGS", " ");
+   Ada_Compiler_Switches := Ada_Compiler_Switches &
+          (
+            "-Og" -- Optimize for debug
+           ,"-ffunction-sections" -- Separate ELF section for each function
+           ,"-fdata-sections" -- Separate ELF section for each variable
+           ,"-g" -- Generate debug info
+           ,"-gnatwa" -- Enable all warnings
+           ,"-gnatw.X" -- Disable warnings for No_Exception_Propagation
+           ,"-gnatVa" -- All validity checks
+           ,"-gnaty3" -- Specify indentation level of 3
+           ,"-gnatya" -- Check attribute casing
+           ,"-gnatyA" -- Use of array index numbers in array attributes
+           ,"-gnatyB" -- Check Boolean operators
+           ,"-gnatyb" -- Blanks not allowed at statement end
+           ,"-gnatyc" -- Check comments
+           ,"-gnaty-d" -- Disable check no DOS line terminators present
+           ,"-gnatye" -- Check end/exit labels
+           ,"-gnatyf" -- No form feeds or vertical tabs
+           ,"-gnatyh" -- No horizontal tabs
+           ,"-gnatyi" -- Check if-then layout
+           ,"-gnatyI" -- check mode IN keywords
+           ,"-gnatyk" -- Check keyword casing
+           ,"-gnatyl" -- Check layout
+           ,"-gnatym" -- Check maximum line length
+           ,"-gnatyn" -- Check casing of entities in Standard
+           ,"-gnatyO" -- Check that overriding subprograms are explicitly marked as such
+           ,"-gnatyp" -- Check pragma casing
+           ,"-gnatyr" -- Check identifier references casing
+           ,"-gnatyS" -- Check no statements after THEN/ELSE
+           ,"-gnatyt" -- Check token spacing
+           ,"-gnatyu" -- Check unnecessary blank lines
+           ,"-gnatyx" -- Check extra parentheses
+           ,"-gnatW8" -- UTF-8 encoding for wide characters
+          );
+
+   type Build_Profile_Kind is ("release", "validation", "development");
+   Build_Profile : Build_Profile_Kind := "development";
+
+end Version_Patcher_Config;
diff --git a/support/version_patcher/config/version_patcher_config.h b/support/version_patcher/config/version_patcher_config.h
new file mode 100644
index 000000000..638f7552b
--- /dev/null
+++ b/support/version_patcher/config/version_patcher_config.h
@@ -0,0 +1,20 @@
+/* Configuration for version_patcher generated by Alire */
+#ifndef VERSION_PATCHER_CONFIG_H
+#define VERSION_PATCHER_CONFIG_H
+
+#define CRATE_VERSION "0.1.0-dev"
+#define CRATE_NAME "version_patcher"
+
+#define ALIRE_HOST_OS "linux"
+
+#define ALIRE_HOST_ARCH "x86_64"
+
+#define ALIRE_HOST_DISTRO "ubuntu"
+
+#define BUILD_PROFILE_RELEASE 1
+#define BUILD_PROFILE_VALIDATION 2
+#define BUILD_PROFILE_DEVELOPMENT 3
+
+#define BUILD_PROFILE  3
+
+#endif
diff --git a/support/version_patcher/src/version_patcher.adb b/support/version_patcher/src/version_patcher.adb
new file mode 100644
index 000000000..b91768447
--- /dev/null
+++ b/support/version_patcher/src/version_patcher.adb
@@ -0,0 +1,117 @@
+with Ada.Command_Line; use Ada.Command_Line;
+with Ada.Directories;
+with Ada.Environment_Variables; use Ada.Environment_Variables;
+with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;
+with Ada.Text_IO;
+
+with GNAT.Expect;
+with GNAT.OS_Lib;
+
+---------------------
+-- Version_Patcher --
+---------------------
+
+procedure Version_Patcher is
+
+   ---------------------
+   -- Replace_Version --
+   ---------------------
+
+   procedure Replace_Version (Filename : String; Build_Info : String) is
+      F : Ada.Text_IO.File_Type;
+      O : Ada.Text_IO.File_Type;
+      use Ada.Text_IO;
+
+      Target : constant String := "Current_Str : constant String :=";
+   begin
+      Open (F, In_File, Filename);
+      Create (O, Out_File, Filename & ".new");
+      while not End_Of_File (F) loop
+         declare
+            Line : constant String := Get_Line (F);
+         begin
+            if (for some I in Line'Range =>
+                  I + Target'Length - 1 <= Line'Last and then
+                  Line (I .. I + Target'Length - 1) = Target)
+            then
+               declare
+                  Quotes_Seen : Boolean := False;
+               begin
+                  for Char of Line loop
+                     if Char = '"' and then not Quotes_Seen then
+                        Quotes_Seen := True;
+                        Put (O, Char);
+                     elsif (Char = '"' and then Quotes_Seen)
+                       or else Char = '+'
+                     then
+                        Put_Line (O, "+" & Build_Info & '"' & ";");
+                        exit;
+                     else
+                        Put (O, Char);
+                     end if;
+                  end loop;
+               end;
+            else
+               Put_Line (O, Line);
+            end if;
+         end;
+      end loop;
+
+      Close (F);
+      Close (O);
+
+      Ada.Directories.Delete_File (Filename);
+      Ada.Directories.Rename (Filename & ".new", Filename);
+
+   end Replace_Version;
+
+   -----------------
+   -- Git_Command --
+   -----------------
+
+   type Result is record
+      Output : Unbounded_String;
+      Code   : Integer;
+   end record;
+
+   function Git_Command (Args : String) return Result is
+      use GNAT.OS_Lib;
+      Arg_List : constant Argument_List_Access :=
+                   Argument_String_To_List (Args);
+      Code : aliased Integer;
+      Output   : constant String
+        := GNAT.Expect.Get_Command_Output
+          ("git", Arg_List.all, "", Code'Access, True);
+   begin
+      return (To_Unbounded_String (Output), Code);
+   end Git_Command;
+
+begin
+   if Exists ("ALR_VERSION_DONT_PATCH") then
+      Ada.Text_IO.Put_Line ("Note: skipping version update");
+      return;
+   end if;
+
+   declare
+      Dirty : constant String
+        := (if Argument_Count > 0 then
+               Argument (1)
+            elsif Git_Command ("diff-index --quiet HEAD --").Code /= 0 then
+               "_dirty"
+            else
+               "");
+      Commit_Result : constant Result :=
+                        Git_Command ("rev-parse --short HEAD");
+      Commit : constant String := To_String (Commit_Result.Output);
+   begin
+      if Commit_Result.Code /= 0 then
+         raise Constraint_Error with
+           "Git error while trying to get commit:"
+           & Commit_Result.Code'Image;
+      end if;
+      Ada.Text_IO.Put_Line
+        ("Updating version in src/alire/alire-version.ads to commit "
+         & Commit & Dirty & "...");
+      Replace_Version ("src/alire/alire-version.ads", Commit & Dirty);
+   end;
+end Version_Patcher;
diff --git a/support/version_patcher/version_patcher.gpr b/support/version_patcher/version_patcher.gpr
new file mode 100644
index 000000000..3a496900e
--- /dev/null
+++ b/support/version_patcher/version_patcher.gpr
@@ -0,0 +1,22 @@
+with "config/version_patcher_config.gpr";
+project Version_Patcher is
+
+   for Source_Dirs use ("src/", "config/");
+   for Object_Dir use "obj/" & Version_Patcher_Config.Build_Profile;
+   for Create_Missing_Dirs use "True";
+   for Exec_Dir use "bin";
+   for Main use ("version_patcher.adb");
+
+   package Compiler is
+      for Default_Switches ("Ada") use Version_Patcher_Config.Ada_Compiler_Switches;
+   end Compiler;
+
+   package Binder is
+      for Switches ("Ada") use ("-Es"); --  Symbolic traceback
+   end Binder;
+
+   package Install is
+      for Artifacts (".") use ("share");
+   end Install;
+
+end Version_Patcher;