diff --git a/include/oi/IntrospectionResult.h b/include/oi/IntrospectionResult.h
index 4bf25f3..13c87b9 100644
--- a/include/oi/IntrospectionResult.h
+++ b/include/oi/IntrospectionResult.h
@@ -21,6 +21,7 @@
 #include <oi/types/dy.h>
 
 #include <cstdint>
+#include <list>
 #include <optional>
 #include <span>
 #include <stack>
@@ -52,6 +53,13 @@ class IntrospectionResult {
     std::optional<result::Element> next_;
 
     std::vector<std::string_view> type_path_;
+    // This field could be more space efficient as these strings are primarily
+    // empty. They are used when the string isn't stored in the .rodata section,
+    // currently when performing key capture. It needs reference stability as we
+    // keep views in type_path_. A std::unique_ptr<std::string> would be an
+    // improvement but it isn't copyable. A string type with size fixed at
+    // construction would also be good.
+    std::list<std::string> dynamic_type_path_;
   };
 
   IntrospectionResult(std::vector<uint8_t> buf, exporters::inst::Inst inst);
diff --git a/include/oi/exporters/Json.h b/include/oi/exporters/Json.h
index 0015e28..31aa808 100644
--- a/include/oi/exporters/Json.h
+++ b/include/oi/exporters/Json.h
@@ -28,7 +28,7 @@ class Json {
 
   void print(const IntrospectionResult&);
   void print(IntrospectionResult::const_iterator& it,
-             IntrospectionResult::const_iterator end);
+             IntrospectionResult::const_iterator& end);
 
   void setPretty(bool pretty) {
     pretty_ = pretty;
diff --git a/oi/IntrospectionResult.cpp b/oi/IntrospectionResult.cpp
index 9c5c844..e44d740 100644
--- a/oi/IntrospectionResult.cpp
+++ b/oi/IntrospectionResult.cpp
@@ -19,6 +19,7 @@
 
 #include <cassert>
 #include <iterator>
+#include <sstream>
 #include <stdexcept>
 
 template <typename T>
@@ -41,6 +42,7 @@ IntrospectionResult::const_iterator::operator++() {
         using U = std::decay_t<decltype(r)>;
         if constexpr (std::is_same_v<U, exporters::inst::PopTypePath>) {
           type_path_.pop_back();
+          dynamic_type_path_.pop_back();
           return operator++();
         } else {
           // reference wrapper
@@ -65,6 +67,40 @@ IntrospectionResult::const_iterator::operator++() {
               handler(
                   *next_, [this](auto i) { stack_.emplace(i); }, parsed);
             }
+
+            std::string& new_name = dynamic_type_path_.emplace_back(std::visit(
+                [](const auto& d) -> std::string {
+                  using V = std::decay_t<decltype(d)>;
+                  if constexpr (std::is_same_v<std::string, V>) {
+                    std::string out = "[";
+                    out.reserve(d.size() + 2);
+                    out += d;
+                    out += "]";
+                    return out;
+                  } else if constexpr (std::is_same_v<result::Element::Pointer,
+                                                      V>) {
+                    std::stringstream out;
+                    out << '[' << reinterpret_cast<void*>(d.p) << ']';
+                    return out.str();
+                  } else if constexpr (std::is_same_v<result::Element::Scalar,
+                                                      V>) {
+                    std::string out = "[";
+                    out += std::to_string(d.n);
+                    out += ']';
+                    return out;
+                  } else if constexpr (std::is_same_v<std::nullopt_t, V>) {
+                    return "";
+                  } else {
+                    static_assert(always_false_v<V>, "missing variant");
+                  }
+                },
+                next_->data));
+            if (!new_name.empty()) {
+              type_path_.back() = new_name;
+              next_->type_path.back() = new_name;
+              next_->name = new_name;
+            }
+
             for (auto it = ty.fields.rbegin(); it != ty.fields.rend(); ++it) {
               stack_.emplace(*it);
             }
diff --git a/oi/exporters/Json.cpp b/oi/exporters/Json.cpp
index 2654252..ad2590e 100644
--- a/oi/exporters/Json.cpp
+++ b/oi/exporters/Json.cpp
@@ -48,16 +48,17 @@ Json::Json(std::ostream& out) : out_(out) {
 
 void Json::print(const IntrospectionResult& r) {
   auto begin = r.cbegin();
-  return print(begin, r.cend());
+  auto end = r.cend();
+  return print(begin, end);
 }
 
 void Json::print(IntrospectionResult::const_iterator& it,
-                 IntrospectionResult::const_iterator end) {
-  std::vector<std::string_view> firstTypePath = it->type_path;
+                 IntrospectionResult::const_iterator& end) {
+  const auto firstTypePathSize = it->type_path.size();
 
-  const auto indent = pretty_ ? makeIndent(firstTypePath.size()) : "";
+  const auto indent = pretty_ ? makeIndent(firstTypePathSize) : "";
   const auto lastIndent =
-      pretty_ ? makeIndent(std::max(firstTypePath.size(), 1UL) - 1) : "";
+      pretty_ ? makeIndent(std::max(firstTypePathSize, 1UL) - 1) : "";
   const auto* tab = pretty_ ? "  " : "";
   const auto* space = pretty_ ? " " : "";
   const auto* endl = pretty_ ? "\n" : "";
@@ -66,7 +67,7 @@ void Json::print(IntrospectionResult::const_iterator& it,
 
   bool first = true;
   while (it != end) {
-    if (it->type_path.size() < firstTypePath.size()) {
+    if (it->type_path.size() < firstTypePathSize) {
       // no longer a sibling, must be a sibling of the type we're printing
       break;
     }
@@ -127,7 +128,7 @@ void Json::print(IntrospectionResult::const_iterator& it,
     }
 
     out_ << tab << "\"members\":" << space;
-    if (++it != end && it->type_path.size() > firstTypePath.size()) {
+    if (++it != end && it->type_path.size() > firstTypePathSize) {
       print(it, end);
     } else {
       out_ << "[]" << endl;
@@ -135,7 +136,7 @@ void Json::print(IntrospectionResult::const_iterator& it,
 
     out_ << indent << "}";
   }
-  if (firstTypePath.size() == 1) {
+  if (firstTypePathSize == 1) {
     out_ << endl << ']' << endl;
   } else {
     out_ << endl << lastIndent << tab << ']' << endl;
diff --git a/test/integration/capture_keys.toml b/test/integration/capture_keys.toml
index c2f9fe2..341dc50 100644
--- a/test/integration/capture_keys.toml
+++ b/test/integration/capture_keys.toml
@@ -55,21 +55,21 @@ class FixedAllocator {
       "typePath": ["a0"],
       "members": [
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[1]",
+          "typePath": ["a0","[1]"],
           "data": 1,
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[1]","key"]},
+            {"name": "value", "typePath": ["a0","[1]","value"]}
           ]
         },
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[3]",
+          "typePath": ["a0","[3]"],
           "data": 3,
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[3]","key"]},
+            {"name": "value", "typePath": ["a0","[3]","value"]}
           ]
         }
       ]
@@ -92,21 +92,21 @@ class FixedAllocator {
       "typePath": ["a0"],
       "members": [
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[abc]",
+          "typePath": ["a0","[abc]"],
           "data": "abc",
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[abc]","key"]},
+            {"name": "value", "typePath": ["a0","[abc]","value"]}
           ]
         },
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[hohoho]",
+          "typePath": ["a0","[hohoho]"],
           "data": "hohoho",
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[hohoho]","key"]},
+            {"name": "value", "typePath": ["a0","[hohoho]","value"]}
           ]
         }
       ]
@@ -125,21 +125,21 @@ class FixedAllocator {
       "typePath": ["a0"],
       "members": [
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[1]",
+          "typePath": ["a0","[1]"],
           "data": 1,
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[1]","key"]},
+            {"name": "value", "typePath": ["a0","[1]","value"]}
           ]
         },
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[3]",
+          "typePath": ["a0","[3]"],
           "data": 3,
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[3]","key"]},
+            {"name": "value", "typePath": ["a0","[3]","value"]}
           ]
         }
       ]
@@ -165,21 +165,21 @@ class FixedAllocator {
       "typePath": ["a0"],
       "members": [
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[0x300020]",
+          "typePath": ["a0","[0x300020]"],
           "data": "0x300020",
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[0x300020]","key"]},
+            {"name": "value", "typePath": ["a0","[0x300020]","value"]}
           ]
         },
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[0x301020]",
+          "typePath": ["a0","[0x301020]"],
           "data": "0x301020",
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
-            {"name": "value", "typePath": ["a0","[]","value"]}
+            {"name": "key", "typePath": ["a0","[0x301020]","key"]},
+            {"name": "value", "typePath": ["a0","[0x301020]","value"]}
           ]
         }
       ]
@@ -207,22 +207,22 @@ class FixedAllocator {
       "typePath": ["a0"],
       "members": [
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[123]",
+          "typePath": ["a0","[123]"],
           "data": 123,
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
+            {"name": "key", "typePath": ["a0","[123]","key"]},
             {
               "name": "value",
-              "typePath": ["a0","[]","value"],
+              "typePath": ["a0","[123]","value"],
               "members": [
                 {
                   "name": "[]",
-                  "typePath": ["a0","[]","value","[]"],
+                  "typePath": ["a0","[123]","value","[]"],
                   "NOT":"data",
                   "members": [
-                    {"name": "key", "typePath": ["a0","[]","value","[]","key"]},
-                    {"name": "value", "typePath": ["a0","[]","value","[]","value"]}
+                    {"name": "key", "typePath": ["a0","[123]","value","[]","key"]},
+                    {"name": "value", "typePath": ["a0","[123]","value","[]","value"]}
                   ]
                 }
               ]
@@ -230,31 +230,31 @@ class FixedAllocator {
           ]
         },
         {
-          "name": "[]",
-          "typePath": ["a0","[]"],
+          "name": "[456]",
+          "typePath": ["a0","[456]"],
           "data": 456,
           "members": [
-            {"name": "key", "typePath": ["a0","[]","key"]},
+            {"name": "key", "typePath": ["a0","[456]","key"]},
             {
               "name": "value",
-              "typePath": ["a0","[]","value"],
+              "typePath": ["a0","[456]","value"],
               "members": [
                 {
                   "name": "[]",
-                  "typePath": ["a0","[]","value","[]"],
+                  "typePath": ["a0","[456]","value","[]"],
                   "NOT":"data",
                   "members": [
-                    {"name": "key", "typePath": ["a0","[]","value","[]","key"]},
-                    {"name": "value", "typePath": ["a0","[]","value","[]","value"]}
+                    {"name": "key", "typePath": ["a0","[456]","value","[]","key"]},
+                    {"name": "value", "typePath": ["a0","[456]","value","[]","value"]}
                   ]
                 },
                 {
                   "name": "[]",
-                  "typePath": ["a0","[]","value","[]"],
+                  "typePath": ["a0","[456]","value","[]"],
                   "NOT":"data",
                   "members": [
-                    {"name": "key", "typePath": ["a0","[]","value","[]","key"]},
-                    {"name": "value", "typePath": ["a0","[]","value","[]","value"]}
+                    {"name": "key", "typePath": ["a0","[456]","value","[]","key"]},
+                    {"name": "value", "typePath": ["a0","[456]","value","[]","value"]}
                   ]
                 }
               ]
@@ -283,21 +283,21 @@ class FixedAllocator {
           "typePath": ["a0","captureMyKeys"],
           "members": [
             {
-              "name": "[]",
-              "typePath": ["a0","captureMyKeys","[]"],
+              "name": "[1]",
+              "typePath": ["a0","captureMyKeys","[1]"],
               "data": 1,
               "members": [
-                {"name": "key", "typePath": ["a0","captureMyKeys","[]","key"]},
-                {"name": "value", "typePath": ["a0","captureMyKeys","[]","value"]}
+                {"name": "key", "typePath": ["a0","captureMyKeys","[1]","key"]},
+                {"name": "value", "typePath": ["a0","captureMyKeys","[1]","value"]}
               ]
             },
             {
-              "name": "[]",
-              "typePath": ["a0","captureMyKeys","[]"],
+              "name": "[3]",
+              "typePath": ["a0","captureMyKeys","[3]"],
               "data": 3,
               "members": [
-                {"name": "key", "typePath": ["a0","captureMyKeys","[]","key"]},
-                {"name": "value", "typePath": ["a0","captureMyKeys","[]","value"]}
+                {"name": "key", "typePath": ["a0","captureMyKeys","[3]","key"]},
+                {"name": "value", "typePath": ["a0","captureMyKeys","[3]","value"]}
               ]
             }
           ]