diff --git a/.gitignore b/.gitignore
index 5860370..ded6e72 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 node_modules/
 coverage/
 .vscode/
+*.d.ts
diff --git a/.npmignore b/.npmignore
index 459d6fa..78e6465 100644
--- a/.npmignore
+++ b/.npmignore
@@ -7,3 +7,4 @@ eslint.config.js
 pnpm-lock.yaml
 test/
 tsconfig.json
+eslint.config.mjs
diff --git a/index.d.ts b/index.d.ts
deleted file mode 100644
index ede748e..0000000
--- a/index.d.ts
+++ /dev/null
@@ -1,70 +0,0 @@
-export = fromMem;
-/**
- * Import or require the given code from memory.  Knows about the different
- * Peggy output formats.  Returns the exports of the module.
- *
- * @param {string} code Code to import
- * @param {FromMemOptions} options Options.  Most important is filename.
- * @returns {Promise<unknown>} The evaluated code.
- */
-declare function fromMem(code: string, options: FromMemOptions): Promise<unknown>;
-declare namespace fromMem {
-    export { guessModuleType, SourceFormat, FromMemOptions, ModuleType };
-}
-/**
- * Figure out the module type for the given file.  If no package.json is
- * found, default to "commonjs".
- *
- * @param {string} filename Fully-qualified filename to start from.
- * @returns {Promise<ModuleType>}
- * @throws On invalid package.json
- */
-declare function guessModuleType(filename: string): Promise<ModuleType>;
-declare namespace guessModuleType {
-    function clearCache(): void;
-}
-type SourceFormat = "amd" | "bare" | "cjs" | "commonjs" | "es" | "es6" | "esm" | "globals" | "guess" | "mjs" | "module" | "umd";
-/**
- * Options for how to process code.
- */
-type FromMemOptions = {
-    /**
-     * What format does the code
-     * have?  "guess" means to read the closest package.json file looking for
-     * the "type" key.  "globals", "amd", and "bare" are not actually supported.
-     */
-    format?: SourceFormat | undefined;
-    /**
-     * If specified, use this instead of the
-     * current values in process.env.  Works if includeGlobals is false by
-     * creating an otherwise-empty process instance.
-     */
-    env?: Record<string, any> | undefined;
-    /**
-     * What is the fully-qualified synthetic filename
-     * for the code?  Most important is the directory, which is used to find
-     * modules that the code import's or require's.
-     */
-    filename: string;
-    /**
-     * Variables to make availble in
-     * the global scope while code is being evaluated.
-     */
-    context?: Record<string, any> | undefined;
-    /**
-     * Include the typical global
-     * properties that node gives to all modules.  (e.g. Buffer, process).
-     */
-    includeGlobals?: boolean | undefined;
-    /**
-     * Specifies the line number offset that is
-     * displayed in stack traces produced by this script.
-     */
-    lineOffset?: number | undefined;
-    /**
-     * Specifies the first-line column number
-     * offset that is displayed in stack traces produced by this script.
-     */
-    columnOffset?: number | undefined;
-};
-type ModuleType = "commonjs" | "es";