diff --git a/build.pro b/build.pro
index 4e49962ab..28cefbab8 100644
--- a/build.pro
+++ b/build.pro
@@ -37,6 +37,14 @@
 #   - if you wish to make packages for Windows, then you must initialize all submodules within repository before compilation,
 #   - C++ 11/17 is required.
 #
+# Building on OS/2:
+#   RSS Guard can run on OS/2 and if you want to compile it by yourself, you need to make sure that
+#   your OS/2 distro is up-to-date and you have all dependencies installed: os2-base, all gcc-* packages,
+#   libc and libcx up-to-date, kbuild-make, ash, binutils, all relevant qt5-* packages.
+#
+#   After your dependecies are installed, then you can compile via standard `qmake -> make -> make install` steps
+#   and package with: 7z.exe a -t7z -mmt -mx9 "rssguard.7z" "<build-folder\src\rssguard\app\*" command.
+#
 # Authors and contributors:
 #   - Martin Rotter (project leader),
 #   - Elbert Pol (OS/2-related contributions).