diff --git a/oi/Features.cpp b/oi/Features.cpp
index 644e7ce..4780e86 100644
--- a/oi/Features.cpp
+++ b/oi/Features.cpp
@@ -45,4 +45,10 @@ const char* featureToStr(Feature f) {
   }
 }
 
+FeatureSet::FeatureSet(std::initializer_list<Feature> features) {
+  for (auto f : features) {
+    (*this)[f] = true;
+  }
+}
+
 }  // namespace ObjectIntrospection
diff --git a/oi/Features.h b/oi/Features.h
index c1a6f16..62ad7c0 100644
--- a/oi/Features.h
+++ b/oi/Features.h
@@ -16,6 +16,7 @@
 #pragma once
 
 #include <array>
+#include <bitset>
 #include <string_view>
 
 #define OI_FEATURE_LIST                         \
@@ -43,4 +44,23 @@ constexpr std::array allFeatures = {
 #undef X
 };
 
+class FeatureSet {
+ private:
+  using BitsetType = std::bitset<allFeatures.size() + 1>;
+
+ public:
+  FeatureSet() = default;
+  FeatureSet(std::initializer_list<Feature>);
+
+  constexpr bool operator[](Feature f) const {
+    return bitset[(size_t)f];
+  }
+  BitsetType::reference operator[](Feature f) {
+    return bitset[(size_t)f];
+  }
+
+ private:
+  BitsetType bitset;
+};
+
 }  // namespace ObjectIntrospection
diff --git a/oi/OICodeGen.cpp b/oi/OICodeGen.cpp
index 9aa5e16..ac494f8 100644
--- a/oi/OICodeGen.cpp
+++ b/oi/OICodeGen.cpp
@@ -62,13 +62,6 @@ std::unique_ptr<OICodeGen> OICodeGen::buildFromConfig(const Config& c,
 
 OICodeGen::OICodeGen(const Config& c, SymbolService& s)
     : config{c}, symbols{s} {
-  chaseRawPointers = config.features.contains(Feature::ChaseRawPointers);
-  packStructs = config.features.contains(Feature::PackStructs);
-  genPaddingStats = config.features.contains(Feature::GenPaddingStats);
-  captureThriftIsset = config.features.contains(Feature::CaptureThriftIsset);
-  polymorphicInheritance =
-      config.features.contains(Feature::PolymorphicInheritance);
-
   // TODO: Should folly::Range just be added as a container?
   auto typesToStub = std::array{
       "SharedMutex",
@@ -998,7 +991,7 @@ bool OICodeGen::recordChildren(drgn_type* type) {
  * types in the program to build the reverse mapping.
  */
 bool OICodeGen::enumerateChildClasses() {
-  if (!polymorphicInheritance) {
+  if (!feature(Feature::PolymorphicInheritance)) {
     return true;
   }
 
@@ -1327,7 +1320,8 @@ bool OICodeGen::isEmptyClassOrFunctionType(drgn_type* type,
  *   one or more virtual member functions or virtual base classes).
  */
 bool OICodeGen::isDynamic(drgn_type* type) const {
-  if (!polymorphicInheritance || !drgn_type_has_virtuality(type)) {
+  if (!feature(Feature::PolymorphicInheritance) ||
+      !drgn_type_has_virtuality(type)) {
     return false;
   }
 
@@ -2008,7 +2002,7 @@ bool OICodeGen::getDrgnTypeNameInt(drgn_type* type, std::string& outName) {
     name.assign(drgn_type_name(type));
   } else if (drgn_type_kind(type) == DRGN_TYPE_POINTER) {
     drgn_type* underlyingType = getPtrUnderlyingType(type);
-    if (chaseRawPointers &&
+    if (feature(Feature::ChaseRawPointers) &&
         drgn_type_kind(underlyingType) != DRGN_TYPE_FUNCTION) {
       // For pointers, figure out name for the underlying type then add
       // appropriate number of '*'
@@ -2278,7 +2272,7 @@ bool OICodeGen::generateStructDef(drgn_type* e, std::string& code) {
 
   std::string structDefinition;
 
-  if (paddingInfo.paddingSize != 0 && genPaddingStats) {
+  if (paddingInfo.paddingSize != 0 && feature(Feature::GenPaddingStats)) {
     structDefinition.append("/* offset    |  size */ ");
   }
 
@@ -2294,7 +2288,8 @@ bool OICodeGen::generateStructDef(drgn_type* e, std::string& code) {
                             std::to_string(*alignment / CHAR_BIT) + ")");
   }
 
-  if (packStructs && (kind == DRGN_TYPE_STRUCT || kind == DRGN_TYPE_CLASS) &&
+  if (feature(Feature::PackStructs) &&
+      (kind == DRGN_TYPE_STRUCT || kind == DRGN_TYPE_CLASS) &&
       violatesAlignmentRequirement && paddingInfo.paddingSize == 0) {
     structDefinition.append(" __attribute__((__packed__))");
   }
@@ -2313,7 +2308,7 @@ bool OICodeGen::generateStructDef(drgn_type* e, std::string& code) {
 
   structDefinition.append("};\n");
 
-  if (genPaddingStats) {
+  if (feature(Feature::GenPaddingStats)) {
     auto paddedStructFound = paddedStructs.find(*tmpStr);
 
     if (paddedStructFound == paddedStructs.end()) {
@@ -2509,7 +2504,8 @@ std::optional<uint64_t> OICodeGen::generateMember(
       currOffsetBits = 0;
       VLOG(1) << "Member size: " << memberSize;
     } else {
-      addSizeComment(genPaddingStats, code, currOffsetBits, memberSize);
+      addSizeComment(feature(Feature::GenPaddingStats), code, currOffsetBits,
+                     memberSize);
       currOffsetBits = currOffsetBits + memberSize;
     }
 
@@ -2709,12 +2705,12 @@ bool OICodeGen::generateStructMembers(
       bool isThriftIssetStruct =
           typeName.starts_with("isset_bitset<") && memberName == "__isset";
 
-      if (captureThriftIsset && isThriftIssetStruct &&
+      if (feature(Feature::CaptureThriftIsset) && isThriftIssetStruct &&
           memberIndex == members.size() - 1) {
         thriftIssetStructTypes.insert(e);
       }
 
-      if (genPaddingStats) {
+      if (feature(Feature::GenPaddingStats)) {
         paddingInfo.isThriftStruct = isThriftIssetStruct;
 
         /*
@@ -3258,12 +3254,12 @@ bool OICodeGen::generateJitCode(std::string& code) {
   functionsCode.append("namespace OIInternal {\nnamespace {\n");
   functionsCode.append("// functions -----\n");
   if (!funcGen.DeclareGetSizeFuncs(functionsCode, containerTypesFuncDef,
-                                   chaseRawPointers)) {
+                                   feature(Feature::ChaseRawPointers))) {
     LOG(ERROR) << "declaring get size for containers failed";
     return false;
   }
 
-  if (chaseRawPointers) {
+  if (feature(Feature::ChaseRawPointers)) {
     functionsCode.append(R"(
     template<typename T>
     void getSizeType(const T* t, size_t& returnArg);
@@ -3284,7 +3280,7 @@ bool OICodeGen::generateJitCode(std::string& code) {
     }
   }
 
-  if (config.useDataSegment || chaseRawPointers) {
+  if (config.useDataSegment || feature(Feature::ChaseRawPointers)) {
     funcGen.DeclareStoreData(functionsCode);
   }
 
@@ -3296,12 +3292,12 @@ bool OICodeGen::generateJitCode(std::string& code) {
   }
 
   if (!funcGen.DefineGetSizeFuncs(functionsCode, containerTypesFuncDef,
-                                  chaseRawPointers)) {
+                                  feature(Feature::ChaseRawPointers))) {
     LOG(ERROR) << "defining get size for containers failed";
     return false;
   }
 
-  if (chaseRawPointers) {
+  if (feature(Feature::ChaseRawPointers)) {
     functionsCode.append(R"(
     template<typename T>
     void getSizeType(const T* s_ptr, size_t& returnArg)
@@ -3780,7 +3776,7 @@ std::vector<std::string> OICodeGen::Config::toOptions() const {
   options.reserve(allFeatures.size());
 
   for (const auto f : allFeatures) {
-    if (features.contains(f)) {
+    if (features[f]) {
       options.emplace_back(std::string("-f") + featureToStr(f));
     } else {
       options.emplace_back(std::string("-F") + featureToStr(f));
diff --git a/oi/OICodeGen.h b/oi/OICodeGen.h
index 0e3a9bf..9c47072 100644
--- a/oi/OICodeGen.h
+++ b/oi/OICodeGen.h
@@ -57,7 +57,7 @@ class OICodeGen {
      */
     bool useDataSegment;
 
-    std::set<Feature> features{};
+    FeatureSet features{};
 
     std::set<fs::path> containerConfigPaths{};
     std::set<std::string> defaultHeaders{};
@@ -113,12 +113,6 @@ class OICodeGen {
   Config config{};
   FuncGen funcGen;
 
-  bool chaseRawPointers;
-  bool packStructs;
-  bool genPaddingStats;
-  bool captureThriftIsset;
-  bool polymorphicInheritance;
-
   using ContainerTypeMapEntry =
       std::pair<std::reference_wrapper<const ContainerInfo>,
                 std::vector<drgn_qualified_type>>;
@@ -185,6 +179,9 @@ class OICodeGen {
     std::unique_ptr<char, FreeDeleter> _data;
   };
 
+  bool feature(Feature f) const {
+    return config.features[f];
+  }
   static void prependQualifiers(enum drgn_qualifiers, std::string& sb);
   static std::string stripFullyQualifiedName(
       const std::string& fullyQualifiedName);
diff --git a/oi/OIDebugger.cpp b/oi/OIDebugger.cpp
index 82072f0..794904c 100644
--- a/oi/OIDebugger.cpp
+++ b/oi/OIDebugger.cpp
@@ -2852,7 +2852,7 @@ bool OIDebugger::processTargetData() {
     const auto& [rootType, typeHierarchy, paddingInfos] = typeInfo->second;
     VLOG(1) << "Root type addr: " << (void*)rootType.type.type;
 
-    if (treeBuilderConfig.features.contains(Feature::GenPaddingStats)) {
+    if (treeBuilderConfig.features[Feature::GenPaddingStats]) {
       paddingHunter.localPaddedStructs = paddingInfos;
       typeTree.setPaddedStructs(&paddingHunter.localPaddedStructs);
     }
@@ -2876,7 +2876,7 @@ bool OIDebugger::processTargetData() {
       continue;
     }
 
-    if (treeBuilderConfig.features.contains(Feature::GenPaddingStats)) {
+    if (treeBuilderConfig.features[Feature::GenPaddingStats]) {
       paddingHunter.processLocalPaddingInfo();
     }
   }
@@ -2890,7 +2890,7 @@ bool OIDebugger::processTargetData() {
     typeTree.dumpJson();
   }
 
-  if (treeBuilderConfig.features.contains(Feature::GenPaddingStats)) {
+  if (treeBuilderConfig.features[Feature::GenPaddingStats]) {
     paddingHunter.outputPaddingInfo();
   }
 
diff --git a/oi/OIUtils.cpp b/oi/OIUtils.cpp
index 0bbd395..cd78b77 100644
--- a/oi/OIUtils.cpp
+++ b/oi/OIUtils.cpp
@@ -31,7 +31,7 @@ namespace OIUtils {
 using namespace ObjectIntrospection;
 using namespace std::literals;
 
-std::optional<std::set<Feature>> processConfigFile(
+std::optional<ObjectIntrospection::FeatureSet> processConfigFile(
     const std::string& configFilePath,
     std::map<Feature, bool> featureMap,
     OICompiler::Config& compilerConfig,
@@ -153,10 +153,10 @@ std::optional<std::set<Feature>> processConfigFile(
     }
   }
 
-  std::set<Feature> featuresSet;
+  ObjectIntrospection::FeatureSet featuresSet;
   for (auto [k, v] : featureMap) {
     if (v) {
-      featuresSet.insert(k);
+      featuresSet[k] = true;
     }
   }
   return featuresSet;
diff --git a/oi/OIUtils.h b/oi/OIUtils.h
index 5d92fc6..1d0f068 100644
--- a/oi/OIUtils.h
+++ b/oi/OIUtils.h
@@ -24,7 +24,7 @@
 
 namespace OIUtils {
 
-std::optional<std::set<Feature>> processConfigFile(
+std::optional<ObjectIntrospection::FeatureSet> processConfigFile(
     const std::string& configFilePath,
     std::map<Feature, bool> featureMap,
     OICompiler::Config& compilerConfig,
diff --git a/oi/TreeBuilder.cpp b/oi/TreeBuilder.cpp
index 400e9f8..23f8fe9 100644
--- a/oi/TreeBuilder.cpp
+++ b/oi/TreeBuilder.cpp
@@ -53,9 +53,6 @@ enum class TrackPointerTag : uint64_t {
 TreeBuilder::TreeBuilder(Config c) : config{std::move(c)} {
   buffer = std::make_unique<msgpack::sbuffer>();
 
-  chaseRawPointers = config.features.contains(Feature::ChaseRawPointers);
-  genPaddingStats = config.features.contains(Feature::GenPaddingStats);
-
   auto testdbPath = "/tmp/testdb_" + std::to_string(getpid());
   if (auto status = rocksdb::DestroyDB(testdbPath, {}); !status.ok()) {
     LOG(FATAL) << "RocksDB error while destroying database: "
@@ -429,7 +426,7 @@ TreeBuilder::Node TreeBuilder::process(NodeID id, Variable variable) {
   if (!variable.isStubbed) {
     switch (drgn_type_kind(variable.type)) {
       case DRGN_TYPE_POINTER:
-        if (chaseRawPointers) {
+        if (config.features[Feature::ChaseRawPointers]) {
           // Pointers to incomplete types are stubbed out
           // See OICodeGen::enumeratePointerType
           if (th->knownDummyTypeList.contains(variable.type)) {
@@ -544,7 +541,7 @@ TreeBuilder::Node TreeBuilder::process(NodeID id, Variable variable) {
         break;
     }
 
-    if (genPaddingStats) {
+    if (config.features[Feature::GenPaddingStats]) {
       auto entry = paddedStructs->find(node.typeName);
       if (entry != paddedStructs->end()) {
         entry->second.instancesCnt++;
diff --git a/oi/TreeBuilder.h b/oi/TreeBuilder.h
index 28f0636..c0c989c 100644
--- a/oi/TreeBuilder.h
+++ b/oi/TreeBuilder.h
@@ -41,7 +41,7 @@ class TreeBuilder {
   struct Config {
     // Don't set default values for the config so the user gets
     // an "unitialized field" warning if he missed any.
-    std::set<ObjectIntrospection::Feature> features;
+    ObjectIntrospection::FeatureSet features;
     bool logAllStructs;
     bool dumpDataSegment;
     std::optional<std::string> jsonPath;
@@ -69,9 +69,6 @@ class TreeBuilder {
   const std::vector<uint64_t>* oidData = nullptr;
   std::map<std::string, PaddingInfo>* paddedStructs = nullptr;
 
-  bool genPaddingStats;
-  bool chaseRawPointers;
-
   /*
    * The RocksDB output needs versioning so they are imported correctly in
    * Scuba. Version 1 had no concept of versioning and no header.
diff --git a/tools/OITB.cpp b/tools/OITB.cpp
index d71216c..b896fec 100644
--- a/tools/OITB.cpp
+++ b/tools/OITB.cpp
@@ -120,10 +120,8 @@ static std::ostream&
 operator<<(std::ostream& out, TreeBuilder::Config tbc) {
   out << "TreeBuilde::Config = [";
   out << "\n  logAllStructs = " << tbc.logAllStructs;
-  out << "\n  chaseRawPointers = "
-      << tbc.features.contains(Feature::ChaseRawPointers);
-  out << "\n  genPaddingStats = "
-      << tbc.features.contains(Feature::GenPaddingStats);
+  out << "\n  chaseRawPointers = " << tbc.features[Feature::ChaseRawPointers];
+  out << "\n  genPaddingStats = " << tbc.features[Feature::GenPaddingStats];
   out << "\n  dumpDataSegment = " << tbc.dumpDataSegment;
   out << "\n  jsonPath = " << (tbc.jsonPath ? *tbc.jsonPath : "NONE");
   out << "\n]\n";
@@ -157,10 +155,10 @@ int main(int argc, char* argv[]) {
             true;  // Weird that we're setting it to true, again...
         break;
       case 'n':
-        tbConfig.features.insert(Feature::ChaseRawPointers);
+        tbConfig.features[Feature::ChaseRawPointers] = true;
         break;
       case 'w':
-        tbConfig.features.erase(Feature::GenPaddingStats);
+        tbConfig.features[Feature::GenPaddingStats] = false;
         break;
       case 'J':
         tbConfig.jsonPath = optarg ? optarg : "oid_out.json";
@@ -189,7 +187,7 @@ int main(int argc, char* argv[]) {
 
   TreeBuilder typeTree(tbConfig);
 
-  if (tbConfig.features.contains(Feature::GenPaddingStats)) {
+  if (tbConfig.features[Feature::GenPaddingStats]) {
     LOG(INFO) << "Setting-up PaddingHunter...";
     typeTree.setPaddedStructs(&paddingInfos);
   }