diff --git a/src/cmake_generator.cpp b/src/cmake_generator.cpp
index 639ef28..c70a3a7 100644
--- a/src/cmake_generator.cpp
+++ b/src/cmake_generator.cpp
@@ -10,7 +10,6 @@
 #include <fstream>
 #include <iomanip>
 #include <new>
-#include <nlohmann/json.hpp>
 #include <regex>
 #include <sstream>
 #include <stdexcept>
@@ -164,7 +163,7 @@ struct Command {
         }
     }
 
-    std::string quote(const std::string &str) {
+    static std::string quote(const std::string &str) {
         // Don't quote arguments that don't need quoting
         if (str.find(' ') == std::string::npos && str.find('\"') == std::string::npos && str.find('/') == std::string::npos &&
             str.find(';') == std::string::npos) {
@@ -582,24 +581,47 @@ void generate_cmake(const char *path, const parser::Project *parent_project) {
         endl();
         // clang-format on
 
-        // Generate vcpkg.json
-        using namespace nlohmann;
-        json j;
-        j["$cmkr"] = "This file is automatically generated from cmake.toml - DO NOT EDIT";
-        j["$cmkr-url"] = cmkr_url;
-        j["$schema"] = "https://raw.githubusercontent.com/microsoft/vcpkg/master/scripts/vcpkg.schema.json";
-        j["name"] = vcpkg_escape_identifier(project.project_name);
-        j["version-string"] = project.project_version;
-        j["dependencies"] = project.vcpkg.packages;
-        if (!project.project_description.empty()) {
-            j["description"] = project.project_description;
-        }
-
+        // Generate vcpkg.json (sorry for the ugly string handling, nlohmann compiles very slowly)
         std::ofstream ofs("vcpkg.json", std::ios::binary);
         if (!ofs) {
             throw std::runtime_error("Failed to create a vcpkg.json manifest file!");
         }
-        ofs << std::setw(2) << j << std::endl;
+        ofs << R"({
+  "$cmkr": "This file is automatically generated from cmake.toml - DO NOT EDIT",
+  "$cmkr-url": "https://github.com/build-cpp/cmkr",
+  "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg/master/scripts/vcpkg.schema.json",
+  "dependencies": [
+)";
+
+        const auto &packages = project.vcpkg.packages;
+        for (size_t i = 0; i < packages.size(); i++) {
+            const auto &package = packages[i];
+            if (!vcpkg_valid_identifier(package)) {
+                throw std::runtime_error("Invalid vcpkg package name '" + package + "'");
+            }
+            ofs << "    \"" << package << '\"';
+            if (i + 1 < packages.size()) {
+                ofs << ',';
+            }
+            ofs << '\n';
+        }
+
+        auto escape = [](const std::string &str) {
+            std::string result;
+            for (auto ch : str) {
+                if (ch == '\\' || ch == '\"') {
+                    result += '\\';
+                }
+                result += ch;
+            }
+            return result;
+        };
+
+        ofs << "  ],\n";
+        ofs << "  \"description\": \"" << escape(project.project_description) << "\",\n";
+        ofs << "  \"name\": \"" << escape(project.project_name) << "\",\n";
+        ofs << R"(  "version-string": "")" << '\n';
+        ofs << "}\n";
     }
 
     if (!project.packages.empty()) {