diff --git a/src/multio/action/Action.h b/src/multio/action/Action.h
index 82f89faf7..aaf010eea 100644
--- a/src/multio/action/Action.h
+++ b/src/multio/action/Action.h
@@ -25,6 +25,7 @@
 #include "ActionStatistics.h"
 #include "eckit/memory/NonCopyable.h"
 #include "multio/config/ComponentConfiguration.h"
+#include "multio/datamod/core/EntryParser.h"
 #include "multio/message/Message.h"
 #include "multio/util/FailureHandling.h"
 
@@ -130,4 +131,16 @@ class ActionBuilder final : public ActionBuilderBase {
 
 //--------------------------------------------------------------------------------------------------
 
+template <typename ParsedConfig>
+ParsedConfig parseConfig(const ComponentConfiguration& compConf) {
+    multio::datamod::ParseOptions opts;
+    opts.allowAdditionalKeys = false;
+
+    auto conf = compConf.parsedConfig();
+    conf.remove("type");
+    conf.remove("next");
+
+    return multio::datamod::readRecordByValue<ParsedConfig>(conf, opts);
+}
+
 }  // namespace multio::action
diff --git a/src/multio/action/encode-mtg2/EncodeMtg2.cc b/src/multio/action/encode-mtg2/EncodeMtg2.cc
index 716c32933..9d5d67bd6 100644
--- a/src/multio/action/encode-mtg2/EncodeMtg2.cc
+++ b/src/multio/action/encode-mtg2/EncodeMtg2.cc
@@ -43,23 +43,9 @@ mars2grib::RawOptions mapOpts(EncodeMtg2Options opts) {
     return ret;
 };
 
-EncodeMtg2Options parseOpts(const ComponentConfiguration& compConf) {
-    /// TODO(pgeier) With C++20 designators are more useful for inline creation of structs:
-    /// ParsedOptions{.allowAdditionalKeys=false}
-    dm::ParseOptions opts;
-    opts.allowAdditionalKeys = false;
-    
-    // TODO(pgeier) Fix after refactoring action - need to remove keys "type" and "next"
-    auto conf = compConf.parsedConfig();
-    conf.remove("type");
-    conf.remove("next");
-    
-    return dm::readRecordByValue<EncodeMtg2Options>(conf, opts);
-}
-
 
 EncodeMtg2::EncodeMtg2(const ComponentConfiguration& compConf) :
-    ChainedAction{compConf}, opts_{parseOpts(compConf)}, mars2grib_{mapOpts(opts_)} {}
+    ChainedAction{compConf}, opts_{parseConfig<EncodeMtg2Options>(compConf)}, mars2grib_{mapOpts(opts_)} {}
 
 
 void EncodeMtg2::executeImpl(Message msg) {
diff --git a/src/multio/action/scale/Scale.cc b/src/multio/action/scale/Scale.cc
index 0c01d659e..6a74c23d0 100644
--- a/src/multio/action/scale/Scale.cc
+++ b/src/multio/action/scale/Scale.cc
@@ -11,7 +11,6 @@
 #include "multio/action/scale/Scale.h"
 
 #include "eckit/config/LocalConfiguration.h"
-#include "eckit/exception/Exceptions.h"
 
 #include "multio/LibMultio.h"
 #include "multio/datamod/ContainerInterop.h"
@@ -21,63 +20,46 @@
 
 namespace multio::action::scale {
 
-const Mappings getMappings(const std::string& preset) {
-    if (preset != "local-to-wmo" && preset != "wmo-to-local") {
-        throw eckit::UserError("Preset " + preset + " does not exist!", Here());
-    }
-
+const std::vector<ScaleMappingConfig> getPresetMappings(const Preset& preset) {
     // Load the mapping file
     eckit::LocalConfiguration mappingConf{eckit::YAMLConfiguration{eckit::PathName{
         multio::LibMultio::instance().libraryHome() + "/share/multio/mappings/local-to-wmo.yaml"
     }}};
 
-    // Read the mappings and put them into the map
-    // We use the same mapping file for local-to-wmo and wmo-to-local, the
-    // second is just the reverse mapping of the first!
-    Mappings mappings;
-    for (auto& mapping : mappingConf.getSubConfigurations()) {
-        const auto paramIn = mapping.getInt64("param-in");
-        const auto paramOut = mapping.getInt64("param-out");
-        const auto scaling = mapping.getDouble("scaling");
-        if (preset == "local-to-wmo") {
-            mappings[paramIn] = {paramOut, scaling};
-        }
-        else {
-            mappings[paramOut] = {paramIn, 1.0 / scaling};
+    auto mappings = datamod::RecordMapper<std::vector<ScaleMappingConfig>>::parse(mappingConf.getSubConfigurations());
+
+    if (preset == Preset::WmoToLocal) {
+        for (auto& mapping : mappings) {
+            std::swap(mapping.paramIn, mapping.paramOut);
+            mapping.scaling.set(1.0 / mapping.scaling.get());
         }
     }
+
     return mappings;
 }
 
-Mappings getMappings(const eckit::LocalConfiguration& config) {
+Mappings getMappings(const ScaleConfig& config) {
     Mappings mappings;
 
     // Read the preset mapping from a mappings file
-    if (config.has("preset-mappings")) {
-        ASSERT(config.isString("preset-mappings"));
-        mappings = getMappings(config.getString("preset-mappings"));
+    if (config.presetMappings.isSet()) {
+        for (auto& mapping : getPresetMappings(config.presetMappings.get())) {
+            mappings[mapping.paramIn.get()] = {mapping.paramOut.get(), mapping.scaling.get()};
+        }
     }
 
     // Read any user defined mappings from the action configuration
-    if (config.has("custom-mappings")) {
-        ASSERT(config.isSubConfigurationList("custom-mappings"));
-        for (auto& mapping : config.getSubConfigurations("custom-mappings")) {
-            const auto paramIn = mapping.getInt64("param-in");
-            const auto paramOut = mapping.getInt64("param-out");
-            const auto scaling = mapping.getDouble("scaling");
-            ASSERT(mappings.find(paramIn) == mappings.end());
-            mappings[paramIn] = {paramOut, scaling};
+    if (config.customMappings.isSet()) {
+        for (auto& mapping : config.customMappings.get()) {
+            mappings[mapping.paramIn.get()] = {mapping.paramOut.get(), mapping.scaling.get()};
         }
     }
 
-    if (mappings.empty()) {
-        throw eckit::UserError("No scale mapping was found, set 'preset' or 'mappings' in action configuration!", Here());
-    }
     return mappings;
 }
 
 Scale::Scale(const ComponentConfiguration& compConf) :
-    ChainedAction(compConf), mappings_{getMappings(compConf.parsedConfig())} {}
+    ChainedAction(compConf), mappings_{getMappings(parseConfig<ScaleConfig>(compConf))} {}
 
 void Scale::executeImpl(message::Message msg) {
     // Skip non-field messages
@@ -133,3 +115,21 @@ void Scale::print(std::ostream& os) const {
 static ActionBuilder<Scale> ScaleBuilder("scale");
 
 }  // namespace multio::action::scale
+
+
+namespace multio::datamod {
+
+action::scale::Preset ParseType<action::scale::Preset>::parse(const std::string& val) {
+    if (val == "local-to-wmo") {
+        return action::scale::Preset::LocalToWmo;
+    }
+    if (val == "wmo-to-local") {
+        return action::scale::Preset::WmoToLocal;
+    }
+    throw DataModellingException(
+        std::string("ParseType<PresetMappings>::parse Unknown value for PresetMappings: ") + val,
+        Here()
+    );
+}
+
+}  // namespace multio::datamod
diff --git a/src/multio/action/scale/Scale.h b/src/multio/action/scale/Scale.h
index d242ba2ad..201cd3e0c 100644
--- a/src/multio/action/scale/Scale.h
+++ b/src/multio/action/scale/Scale.h
@@ -1,7 +1,10 @@
 #pragma once
 
+#include "eckit/exception/Exceptions.h"
+
 #include "multio/action/ChainedAction.h"
 #include "multio/datamod/core/EntryDef.h"
+#include "multio/datamod/core/NestedRecord.h"
 #include "multio/datamod/MarsKeys.h"
 #include "multio/datamod/GribKeys.h"
 
@@ -23,37 +26,51 @@ struct ScaleMetadataKeys {
 };
 
 //------------------------ Action Configuration Keys ------------------------//
-//
-// TODO: Support (lists of) sub-records in datamod
-//
-// struct ScaleMappingKeys {
-//     dm::Entry<std::int64_t> paramIn;
-//     dm::Entry<std::int64_t> paramOut;
-//     dm::Entry<double> scaling;
-//
-//     static constexpr std::string_view record_name_ = "scale-mapping-keys";
-//
-//     using SMK = ScaleMappingKeys;
-//     static constexpr auto record_entries_ = std::make_tuple(
-//         dm::entryDef("param-in", &SMK::paramIn),
-//         dm::entryDef("param-out", &SMK::paramOut),
-//         dm::entryDef("scaling", &SMK::scaling)
-//     );
-// };
-//
-// struct ScaleConfigurationKeys {
-//     dm::Entry<std::string> presetMappings;
-//     dm::Entry<std::List<ScaleMappingKeys>> customMappings;
-//
-//     static constexpr std::string_view record_name_ = "scale-action-configuration";
-//
-//     using SCK = ScaleConfigurationKeys;
-//     static constexpr auto record_entries_ = std::make_tuple(
-//         dm::entryDef("preset-mappings", &SCK::presetMappings).tagOptional(),
-//         dm::entryDef("custom-mappings", &SCK::customMappings).tagOptional()
-//     );
-// };
-//
+
+enum class Preset : std::size_t
+{
+    LocalToWmo,  // "local-to-wmo"
+    WmoToLocal   // "wmo-to-local"
+};
+
+struct ScaleMappingConfig {
+    dm::Entry<std::int64_t> paramIn;
+    dm::Entry<std::int64_t> paramOut;
+    dm::Entry<double> scaling;
+
+    static constexpr std::string_view record_name_ = "scale-mapping-config";
+
+    static constexpr auto record_entries_ = std::make_tuple(
+        dm::entryDef("param-in", &ScaleMappingConfig::paramIn),
+        dm::entryDef("param-out", &ScaleMappingConfig::paramOut),
+        dm::entryDef("scaling", &ScaleMappingConfig::scaling)
+    );
+};
+
+struct ScaleConfig {
+    dm::Entry<Preset> presetMappings;
+    dm::NestedEntry_t<std::vector<ScaleMappingConfig>> customMappings;
+
+    static constexpr std::string_view record_name_ = "scale-action-config";
+
+    static constexpr auto record_entries_ = std::make_tuple(
+        dm::entryDef("preset-mappings", &ScaleConfig::presetMappings).tagOptional(),
+
+        // Custom mappings are user defined mappings that will be applied on top of a preset, if a mapping from a
+        // param already exists, it will be overwritten by the custom mapping.
+        dm::entryDef("custom-mappings", &ScaleConfig::customMappings).tagOptional()
+    );
+
+    static void validate(const ScaleConfig& k) {
+        if (!k.presetMappings.isSet() && (!k.customMappings.isSet() || k.customMappings.get().empty())) {
+            throw eckit::UserError(
+                "Either 'preset-mappings' or 'custom-mappings' must be set in scale action configuration!",
+                Here()
+            );
+        }
+    }
+};
+
 //---------------------------------------------------------------------------//
 
 using Param = std::int64_t;
@@ -78,3 +95,28 @@ class Scale final : public ChainedAction {
 };
 
 }  // namespace multio::action::scale
+
+
+namespace multio::util {
+
+template <>
+struct TypeToString<action::scale::ScaleMappingConfig> {
+    std::string operator()() const { return std::string("ScaleMappingConfig"); };
+};
+
+template <>
+struct TypeToString<action::scale::Preset> {
+    std::string operator()() const { return std::string("PresetMappings"); };
+};
+
+}  // namespace multio::util
+
+
+namespace multio::datamod {
+
+template <>
+struct ParseType<action::scale::Preset> {
+    static action::scale::Preset parse(const std::string& s);
+};
+
+}  // namespace multio::datamod
diff --git a/src/multio/datamod/ContainerInterop.h b/src/multio/datamod/ContainerInterop.h
index c05e06fc4..99a06fdc4 100644
--- a/src/multio/datamod/ContainerInterop.h
+++ b/src/multio/datamod/ContainerInterop.h
@@ -269,9 +269,6 @@ struct EntryParser<eckit::Configuration> {
         if (c.isIntegralList(key)) {
             return std::forward<Func>(func)(util::TypeTag<std::vector<double>>{});
         }
-        // if (c.isList(key)) {
-        //     // Not supported
-        // }
         if (c.isString(key)) {
             return std::forward<Func>(func)(util::TypeTag<std::string>{});
         }
@@ -281,6 +278,9 @@ struct EntryParser<eckit::Configuration> {
         if (c.isSubConfiguration(key)) {
             return std::forward<Func>(func)(util::TypeTag<eckit::LocalConfiguration>{});
         }
+        if (c.isSubConfigurationList(key)) {
+            return std::forward<Func>(func)(util::TypeTag<std::vector<eckit::LocalConfiguration>>{});
+        }
 
         return std::forward<Func>(func)();
     }
diff --git a/src/multio/datamod/core/NestedRecord.h b/src/multio/datamod/core/NestedRecord.h
index 4bed84784..3bb951b23 100644
--- a/src/multio/datamod/core/NestedRecord.h
+++ b/src/multio/datamod/core/NestedRecord.h
@@ -10,6 +10,8 @@
 
 #pragma once
 
+#include <vector>
+
 #include "multio/datamod/core/EntryDef.h"
 #include "multio/datamod/core/EntryDumper.h"
 #include "multio/datamod/core/EntryParser.h"
@@ -57,6 +59,26 @@ struct RecordMapper {
 };
 
 
+template <typename RecordType>
+struct RecordMapper<std::vector<RecordType>> {
+    // Parse record from other record or implemented container
+    template <
+        typename OtherRec,
+        std::enable_if_t<IsRecord_v<OtherRec> || EntryParserIsSpecialized_v<OtherRec>, bool>
+        = true>
+    static std::vector<RecordType> parse(const std::vector<OtherRec>& vec) {
+        std::vector<RecordType> res;
+        res.reserve(vec.size());
+        for (const auto& v : vec) {
+            res.push_back(readRecordByValue<RecordType>(v));
+        }
+        return res;
+    }
+
+    // Dumping of vector is not implemented
+};
+
+
 template <typename RecordType>
 using NestedEntry_t = Entry<RecordType, RecordMapper<RecordType>>;