add varnam pkg

flake.nix

@@ -26,6 +26,8 @@
           ];
         };
         packages = rec {
+          libgovarnam = pkgs.callPackage ./govarnam/default.nix { };
+          varnam-cli = pkgs.callPackage ./govarnam/default.nix { cli = true; };
         };
       }
     );

govarnam/default.nix

@@ -0,0 +1,66 @@
+{ lib
+, buildGoModule
+, fetchFromGitHub
+, pkg-config
+, cli ? false
+}:
+
+buildGoModule rec {
+  pname = "libgovarnam";
+  version = "1.9.1";
+
+  src = fetchFromGitHub {
+    owner = "varnamproject";
+    repo = "govarnam";
+    rev = "v${version}";
+    hash = "sha256-7SYdeOMgc8VBx0rsu6tWGND9mq0Td1VeGmZrpfsWsVE=";
+    fetchSubmodules = true;
+  };
+
+  vendorHash = "sha256-a7m2THvdi17muJI6p6OVX9cBMcmocYwju29beG2H8CY=";
+
+  CGO_ENABLED = 1;
+
+  nativeBuildInputs = [ pkg-config ];
+
+  buildPhase =
+    let buildcli = ''go build -o varnamcli -ldflags "-s -w -X 'github.com/varnamproject/govarnam/govarnam.BuildString=${version} (\#0000000 1970-01-01T00:00:00+0000)' -X 'github.com/varnamproject/govarnam/govarnam.VersionString=${version}'" ./cli'';
+    in ''
+      runHook preInstall
+
+      go build -tags "fts5" -buildmode=c-shared -ldflags "-s -w -X 'github.com/varnamproject/govarnam/govarnam.BuildString=${version} (\#0000000 1970-01-01T00:00:00+0000)' -X 'github.com/varnamproject/govarnam/govarnam.VersionString=${version}' -extldflags "-Wl,-soname,${pname}.so.1,--version-script,${src}/govarnam.syms"" -o ${pname}.so .
+      ${lib.optionalString cli "${buildcli}"}
+
+      runHook postInstall
+    '';
+
+  installPhase = ''
+    runHook preInstall
+
+    mkdir -p $out/lib
+    cp ${pname}.so $out/lib/${pname}.so.${version}
+    ln -s $out/lib/${pname}.so.${version} $out/lib/${pname}.so
+    ln -s $out/lib/${pname}.so.${version} $out/lib/${pname}.so.1
+
+    mkdir -p $out/lib/pkgconfig
+    cp govarnam.pc.in $out/lib/pkgconfig/govarnam.pc
+    sed -i "s#@INSTALL_PREFIX@#$out/lib#g" $out/lib/pkgconfig/govarnam.pc
+
+    mkdir -p $out/include/${pname}
+    cp *.h $out/include/${pname}/
+
+    ${lib.optionalString cli "install -Dt $out/bin varnamcli"}
+
+    runHook postInstall
+  '';
+
+
+  meta = {
+    description = "Easily type Indic languages on computer and mobile. GoVarnam is a cross-platform transliteration library. Manglish -> Malayalam, Thanglish -> Tamil, Hinglish -> Hindi plus another 10 languages. GoVarnam is a near-Go port of libvarnam";
+    homepage = "https://github.com/varnamproject/govarnam";
+    license = lib.licenses.agpl3Only;
+    maintainers = with lib.maintainers; [ adtya ];
+    pkgConfigModules = [ "libgovarnam" ];
+
+  };
+}