diff --git a/launcher/modplatform/ModIndex.cpp b/launcher/modplatform/ModIndex.cpp
index fc79dff15..5b7624563 100644
--- a/launcher/modplatform/ModIndex.cpp
+++ b/launcher/modplatform/ModIndex.cpp
@@ -117,7 +117,7 @@ QString getMetaURL(ResourceProvider provider, QVariant projectID)
            projectID.toString();
 }
 
-auto getModLoaderString(ModLoaderType type) -> const QString
+auto getModLoaderAsString(ModLoaderType type) -> const QString
 {
     switch (type) {
         case NeoForge:
@@ -138,4 +138,21 @@ auto getModLoaderString(ModLoaderType type) -> const QString
     return "";
 }
 
+auto getModLoaderFromString(QString type) -> const ModLoaderType
+{
+    if (type == "neoforge")
+        return NeoForge;
+    if (type == "forge")
+        return Forge;
+    if (type == "cauldron")
+        return Cauldron;
+    if (type == "liteloader")
+        return LiteLoader;
+    if (type == "fabric")
+        return Fabric;
+    if (type == "quilt")
+        return Quilt;
+    return {};
+}
+
 }  // namespace ModPlatform
diff --git a/launcher/modplatform/ModIndex.h b/launcher/modplatform/ModIndex.h
index 72294c399..940dddea0 100644
--- a/launcher/modplatform/ModIndex.h
+++ b/launcher/modplatform/ModIndex.h
@@ -109,6 +109,7 @@ struct IndexedVersion {
     bool is_preferred = true;
     QString changelog;
     QList<Dependency> dependencies;
+    QString side;  // this is for flame API
 
     // For internal use, not provided by APIs
     bool is_currently_selected = false;
@@ -181,7 +182,8 @@ inline auto getOverrideDeps() -> QList<OverrideDep>
 
 QString getMetaURL(ResourceProvider provider, QVariant projectID);
 
-auto getModLoaderString(ModLoaderType type) -> const QString;
+auto getModLoaderAsString(ModLoaderType type) -> const QString;
+auto getModLoaderFromString(QString type) -> const ModLoaderType;
 
 constexpr bool hasSingleModLoaderSelected(ModLoaderTypes l) noexcept
 {
diff --git a/launcher/modplatform/flame/FlameModIndex.cpp b/launcher/modplatform/flame/FlameModIndex.cpp
index 345883c17..75c10d6f5 100644
--- a/launcher/modplatform/flame/FlameModIndex.cpp
+++ b/launcher/modplatform/flame/FlameModIndex.cpp
@@ -130,6 +130,12 @@ auto FlameMod::loadIndexedPackVersion(QJsonObject& obj, bool load_changelog) ->
             file.loaders |= ModPlatform::Fabric;
         if (loader == "quilt")
             file.loaders |= ModPlatform::Quilt;
+        if (loader == "server" || loader == "client") {
+            if (file.side.isEmpty())
+                file.side = loader;
+            else if (file.side != loader)
+                file.side = "both";
+        }
     }
 
     file.addonId = Json::requireInteger(obj, "modId");
diff --git a/launcher/modplatform/modrinth/ModrinthAPI.h b/launcher/modplatform/modrinth/ModrinthAPI.h
index d0f0811b2..857719902 100644
--- a/launcher/modplatform/modrinth/ModrinthAPI.h
+++ b/launcher/modplatform/modrinth/ModrinthAPI.h
@@ -41,7 +41,7 @@ class ModrinthAPI : public NetworkResourceAPI {
         for (auto loader :
              { ModPlatform::NeoForge, ModPlatform::Forge, ModPlatform::Fabric, ModPlatform::Quilt, ModPlatform::LiteLoader }) {
             if (types & loader) {
-                l << getModLoaderString(loader);
+                l << getModLoaderAsString(loader);
             }
         }
         return l;
diff --git a/launcher/modplatform/packwiz/Packwiz.cpp b/launcher/modplatform/packwiz/Packwiz.cpp
index e35567f24..90d7d0ed7 100644
--- a/launcher/modplatform/packwiz/Packwiz.cpp
+++ b/launcher/modplatform/packwiz/Packwiz.cpp
@@ -113,7 +113,8 @@ auto V1::createModFormat([[maybe_unused]] QDir& index_dir, ModPlatform::IndexedP
     mod.provider = mod_pack.provider;
     mod.file_id = mod_version.fileId;
     mod.project_id = mod_pack.addonId;
-    mod.side = stringToSide(mod_pack.side);
+    mod.side = stringToSide(mod_version.side.isEmpty() ? mod_pack.side : mod_version.side);
+    mod.loaders = mod_version.loaders;
 
     return mod;
 }
@@ -181,6 +182,14 @@ void V1::updateModIndex(QDir& index_dir, Mod& mod)
             break;
     }
 
+    toml::array loaders;
+    for (auto loader : { ModPlatform::NeoForge, ModPlatform::Forge, ModPlatform::Cauldron, ModPlatform::LiteLoader, ModPlatform::Fabric,
+                         ModPlatform::Quilt }) {
+        if (mod.loaders & loader) {
+            loaders.push_back(getModLoaderAsString(loader));
+        }
+    }
+
     if (!index_file.open(QIODevice::ReadWrite)) {
         qCritical() << QString("Could not open file %1!").arg(normalized_fname);
         return;
@@ -192,6 +201,7 @@ void V1::updateModIndex(QDir& index_dir, Mod& mod)
         auto tbl = toml::table{ { "name", mod.name.toStdString() },
                                 { "filename", mod.filename.toStdString() },
                                 { "side", sideToString(mod.side).toStdString() },
+                                { "loader", loaders },
                                 { "download",
                                   toml::table{
                                       { "mode", mod.mode.toStdString() },
@@ -276,6 +286,13 @@ auto V1::getIndexForMod(QDir& index_dir, QString slug) -> Mod
         mod.name = stringEntry(table, "name");
         mod.filename = stringEntry(table, "filename");
         mod.side = stringToSide(stringEntry(table, "side"));
+        if (auto loaders = table["loaders"]; loaders && loaders.is_array()) {
+            for (auto&& loader : *loaders.as_array()) {
+                if (loader.is_string()) {
+                    mod.loaders |= ModPlatform::getModLoaderFromString(QString::fromStdString(loader.as_string()->value_or("")));
+                }
+            }
+        }
     }
 
     {  // [download] info
diff --git a/launcher/modplatform/packwiz/Packwiz.h b/launcher/modplatform/packwiz/Packwiz.h
index dce198b0e..a61bb0503 100644
--- a/launcher/modplatform/packwiz/Packwiz.h
+++ b/launcher/modplatform/packwiz/Packwiz.h
@@ -41,6 +41,7 @@ class V1 {
         QString name{};
         QString filename{};
         Side side{ Side::UniversalSide };
+        ModPlatform::ModLoaderTypes loaders;
 
         // [download]
         QString mode{};