diff --git a/lib/std/encoding/json_marshal.c3 b/lib/std/encoding/json_marshal.c3
new file mode 100644
index 000000000..a2481b8f6
--- /dev/null
+++ b/lib/std/encoding/json_marshal.c3
@@ -0,0 +1,164 @@
+// Copyright (c) 2024 C3 Community. All rights reserved.
+// Use of this source code is governed by the MIT license
+// a copy of which can be found in the LICENSE_STDLIB file.
+
+<*
+ JSON marshaling for structs containing primitive types, enums, and nested structs.
+ Supports: String, int, float, double, bool, enums (always marshaled as enum names), nested structs
+*>
+
+module std::encoding::json;
+import std::core::string;
+
+faultdef UNSUPPORTED_TYPE;
+
+<*
+ Marshal a struct with primitive fields and nested structs to JSON.
+
+ @param allocator: "The allocator to use for the result"
+ @param value: "The struct value to marshal"
+ @require @typekind(value) == STRUCT
+ @return "The JSON string representation"
+*>
+macro String? marshal(Allocator allocator, value)
+{
+    var $Type = $typeof(value);
+
+    DString result = dstring::new_with_capacity(allocator, 32);
+    defer result.free();
+
+    result.append_char('{');
+
+    var $first = true;
+    $foreach $member : $Type.membersof:
+        $if $member.nameof != "":
+            $if !$first:
+                result.append_char(',');
+            $endif
+            $first = false;
+
+            // Add field name (always quoted)
+            result.append_char('"');
+            result.append($member.nameof);
+            result.append(`":`);
+
+            // Add field value using common marshaling logic
+            @pool()
+            {
+                String field_result = tmarshal_value($member.get(value))!;
+                result.append(field_result);
+            };
+        $endif
+    $endforeach
+
+    result.append_char('}');
+    return result.copy_str(allocator);
+}
+
+<*
+ Marshal a struct with primitive fields and nested structs to JSON using the temp allocator.
+
+ @param value: "The struct value to marshal"
+ @require @typekind(value) == STRUCT
+ @return "The JSON string representation"
+*>
+macro String? tmarshal(value) => marshal(tmem, value);
+
+<*
+ Marshal a primitive value to JSON.
+
+ @param allocator: "The allocator to use for the result"
+ @param value: "The value to marshal"
+ @return "The JSON string representation"
+*>
+macro String? marshal_value(Allocator allocator, value)
+{
+    var $Type = $typeof(value);
+
+    $switch $Type.kindof:
+        $case STRUCT:
+            return marshal(allocator, value);
+        $case ARRAY:
+        $case SLICE:
+            return marshal_array(allocator, value);
+        $case SIGNED_INT:
+        $case UNSIGNED_INT:
+            return string::tformat("%d", value);
+        $case FLOAT:
+            return string::tformat("%g", value);
+        $case BOOL:
+            return value ? "true" : "false";
+        $case ENUM:
+            return marshal_enum(value);
+        $default:
+            $if $Type.typeid == String.typeid:
+                return value.tescape(false);
+            $endif
+            return UNSUPPORTED_TYPE?;
+    $endswitch
+}
+
+<*
+ Marshal a primitive value to JSON using the temp allocator.
+
+ @param value: "The value to marshal"
+ @return "The JSON string representation"
+*>
+macro String? tmarshal_value(value) => marshal_value(tmem, value);
+
+<*
+ Marshal an array of primitive values to JSON.
+
+ @param allocator: "The allocator to use for the result"
+ @param array: "The array to marshal"
+ @return "The JSON array string representation"
+*>
+macro String? marshal_array(Allocator allocator, array)
+{
+    DString result = dstring::new_with_capacity(allocator, 32);
+    defer result.free();
+
+    result.append_char('[');
+
+    foreach (i, element : array)
+    {
+        if (i > 0) result.append_char(',');
+
+        // Use common marshaling logic for each element
+        @pool()
+        {
+            String element_result = tmarshal_value(element)!;
+            result.append(element_result);
+        };
+    }
+
+    result.append_char(']');
+    return result.copy_str(allocator);
+}
+
+<*
+ Marshal an array of primitive values to JSON using the temp allocator.
+
+ @param array: "The array to marshal"
+ @return "The JSON array string representation"
+*>
+macro String? tmarshal_array(array) => marshal_array(tmem, array);
+
+<*
+ Marshal an enum value to JSON as a quoted string.
+ Always uses the enum name, regardless of associated values.
+
+ @param enum_value: "The enum value to marshal"
+ @return "The JSON string representation"
+*>
+macro String? marshal_enum(enum_value)
+{
+    var $Type = $typeof(enum_value);
+
+    // Convert enum to ordinal and get the name
+    usz ordinal = types::any_to_enum_ordinal(&enum_value, usz)!!;
+    assert(ordinal < $Type.names.len, "Illegal enum value found, numerical value was %d.", ordinal);
+
+    // Always use enum names for JSON marshaling
+    return $Type.names[ordinal].tescape(false);
+}
diff --git a/test/unit/stdlib/encoding/json_marshal.c3 b/test/unit/stdlib/encoding/json_marshal.c3
new file mode 100644
index 000000000..8047594dc
--- /dev/null
+++ b/test/unit/stdlib/encoding/json_marshal.c3
@@ -0,0 +1,255 @@
+module json_marshal_test @test;
+import std::encoding::json;
+import std::collections::object;
+import std::io;
+
+// Test enums
+enum Status
+{
+    ACTIVE,
+    INACTIVE,
+    PENDING
+}
+
+enum Priority
+{
+    LOW,
+    MEDIUM,
+    HIGH
+}
+
+// Enum with associated value
+enum State : int (String description)
+{
+    WAITING = "waiting",
+    RUNNING = "running",
+    TERMINATED = "ended"
+}
+
+// Basic structures
+struct Address
+{
+    String street;
+    String city;
+    int zip_code;
+}
+
+struct Person
+{
+    String name;
+    int age;
+    bool is_active;
+    double height;
+    Status status;
+}
+
+// Complex structure with all features
+struct ComplexData
+{
+    // Primitive types
+    String text;
+    int integer;
+    float single_precision;
+    double double_precision;
+    bool flag;
+
+    // Enums
+    Status status;
+    Priority priority;
+    State current_state;
+
+    // Nested struct
+    Person owner;
+    Address location;
+
+    // Arrays of primitives
+    String[] tags;
+    int[] numbers;
+    float[] ratings;
+    bool[] flags;
+
+    // Array of structs
+    Address[] offices;
+    Person[] team_members;
+
+    // Array of arrays
+    int[][] matrix;
+    String[][] categories;
+}
+
+fn void test_comprehensive_marshaling() @test
+{
+    // Create a complex data structure with all supported features
+    ComplexData data = {
+        // Primitive types
+        .text = "Hello \"World\"",
+        .integer = 42,
+        .single_precision = 3.14,
+        .double_precision = 2.718281828,
+        .flag = true,
+
+        // Enums
+        .status = Status.ACTIVE,
+        .priority = Priority.HIGH,
+        .current_state = State.RUNNING,
+
+        // Nested structs
+        .owner = {
+            .name = "John Doe",
+            .age = 30,
+            .is_active = true,
+            .height = 5.9,
+            .status = Status.ACTIVE
+        },
+        .location = {
+            .street = "123 Main St",
+            .city = "New York",
+            .zip_code = 10001
+        },
+
+        // Arrays of primitives
+        .tags = { "important", "urgent", "review" },
+        .numbers = { 1, 2, 3, 4, 5 },
+        .ratings = { 4.5, 3.8, 4.9 },
+        .flags = { true, false, true },
+
+        // Array of structs
+        .offices = {
+            {
+                .street = "100 Tech Blvd",
+                .city = "Austin",
+                .zip_code = 78701
+            },
+            {
+                .street = "200 Innovation Dr",
+                .city = "Seattle",
+                .zip_code = 98101
+            }
+        },
+        .team_members = {
+            {
+                .name = "Alice Smith",
+                .age = 28,
+                .is_active = true,
+                .height = 5.6,
+                .status = Status.ACTIVE
+            },
+            {
+                .name = "Bob Johnson",
+                .age = 35,
+                .is_active = false,
+                .height = 6.1,
+                .status = Status.INACTIVE
+            }
+        },
+
+        // Array of arrays
+        .matrix = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } },
+        .categories = { { "tech", "programming" }, { "business", "finance" } }
+    };
+
+    // Marshal the complex data structure
+    String json = json::marshal(mem, data)!!;
+    defer free(json);
+
+    // Parse the marshaled JSON back to verify it's valid and correct
+    Object* parsed = json::tparse_string(json)!!;
+
+    // Verify primitive types
+    assert(parsed.get_string("text")!! == "Hello \"World\"");
+    assert(parsed.get_int("integer")!! == 42);
+    assert(parsed.get_float("single_precision")!! == 3.14f);
+    assert(parsed.get_bool("flag")!! == true);
+
+    // Verify enums (marshaled as strings)
+    assert(parsed.get_string("status")!! == "ACTIVE");
+    assert(parsed.get_string("priority")!! == "HIGH");
+    assert(parsed.get_string("current_state")!! == "RUNNING");
+
+    // Verify nested structs
+    Object* owner = parsed.get("owner")!!;
+    assert(owner.get_string("name")!! == "John Doe");
+    assert(owner.get_int("age")!! == 30);
+    assert(owner.get_bool("is_active")!! == true);
+    assert(owner.get_float("height")!! == 5.9f);
+    assert(owner.get_string("status")!! == "ACTIVE");
+
+    Object* location = parsed.get("location")!!;
+    assert(location.get_string("street")!! == "123 Main St");
+    assert(location.get_string("city")!! == "New York");
+    assert(location.get_int("zip_code")!! == 10001);
+
+    // Verify arrays of primitives
+    Object* tags = parsed.get("tags")!!;
+    assert(tags.get_len() == 3);
+    assert(tags.get_string_at(0)!! == "important");
+    assert(tags.get_string_at(1)!! == "urgent");
+    assert(tags.get_string_at(2)!! == "review");
+
+    Object* numbers = parsed.get("numbers")!!;
+    assert(numbers.get_len() == 5);
+    assert(numbers.get_int_at(0)!! == 1);
+    assert(numbers.get_int_at(4)!! == 5);
+
+    Object* ratings = parsed.get("ratings")!!;
+    assert(ratings.get_len() == 3);
+    assert(ratings.get_float_at(0)!! == 4.5f);
+    assert(ratings.get_float_at(2)!! == 4.9f);
+
+    Object* flags = parsed.get("flags")!!;
+    assert(flags.get_len() == 3);
+    assert(flags.get_bool_at(0)!! == true);
+    assert(flags.get_bool_at(1)!! == false);
+    assert(flags.get_bool_at(2)!! == true);
+
+    // Verify array of structs
+    Object* offices = parsed.get("offices")!!;
+    assert(offices.get_len() == 2);
+
+    Object* first_office = offices.get_at(0);
+    assert(first_office.get_string("street")!! == "100 Tech Blvd");
+    assert(first_office.get_string("city")!! == "Austin");
+    assert(first_office.get_int("zip_code")!! == 78701);
+
+    Object* second_office = offices.get_at(1);
+    assert(second_office.get_string("street")!! == "200 Innovation Dr");
+    assert(second_office.get_string("city")!! == "Seattle");
+    assert(second_office.get_int("zip_code")!! == 98101);
+
+    Object* team_members = parsed.get("team_members")!!;
+    assert(team_members.get_len() == 2);
+
+    Object* alice = team_members.get_at(0);
+    assert(alice.get_string("name")!! == "Alice Smith");
+    assert(alice.get_int("age")!! == 28);
+    assert(alice.get_bool("is_active")!! == true);
+    assert(alice.get_string("status")!! == "ACTIVE");
+
+    Object* bob = team_members.get_at(1);
+    assert(bob.get_string("name")!! == "Bob Johnson");
+    assert(bob.get_int("age")!! == 35);
+    assert(bob.get_bool("is_active")!! == false);
+    assert(bob.get_string("status")!! == "INACTIVE");
+
+    // Verify array of arrays
+    Object* matrix = parsed.get("matrix")!!;
+    assert(matrix.get_len() == 3);
+
+    Object* first_row = matrix.get_at(0);
+    assert(first_row.get_len() == 3);
+    assert(first_row.get_int_at(0)!! == 1);
+    assert(first_row.get_int_at(1)!! == 2);
+    assert(first_row.get_int_at(2)!! == 3);
+
+    Object* categories = parsed.get("categories")!!;
+    assert(categories.get_len() == 2);
+
+    Object* first_category = categories.get_at(0);
+    assert(first_category.get_len() == 2);
+    assert(first_category.get_string_at(0)!! == "tech");
+    assert(first_category.get_string_at(1)!! == "programming");
+
+    // Verify JSON format
+    assert(json.starts_with("{"));
+    assert(json.ends_with("}"));
+}
\ No newline at end of file