diff --git a/scripts/debug-render-example.ts b/scripts/debug-render-example.ts
index d1dabca..736dca1 100644
--- a/scripts/debug-render-example.ts
+++ b/scripts/debug-render-example.ts
@@ -5,20 +5,20 @@ import * as path from "node:path";
 
 import remarkFrontmatter from "remark-frontmatter";
 
-import rehypeAddSlug from "../src/rehype-add-slug";
-import rehypeReplaceText from "../src/rehype-replace-text";
-import rehypeKatex from "../src/rehype-katex";
-import rehypeWrap from "../src/rehype-wrap";
-import rehypeCounter from "../src/rehype-counter";
-import rehypeCleanInternal from "../src/rehype-clean-internal";
+import rehypeAddSlug from "../src/rehype-add-slug.js";
+import rehypeReplaceText from "../src/rehype-replace-text.js";
+import rehypeKatex from "../src/rehype-katex.js";
+import rehypeWrap from "../src/rehype-wrap.js";
+import rehypeCounter from "../src/rehype-counter.js";
+import rehypeCleanInternal from "../src/rehype-clean-internal.js";
 // import rehypeDebug from "../src/rehype-debug";
 // import remarkDebug from "../src/remark-debug";
-import remarkTerm from "../src/remark-term";
-import remarkMeta from "../src/remark-meta";
-import rehypeSave from "../src/rehype-save";
+import remarkTerm from "../src/remark-term.js";
+import remarkMeta from "../src/remark-meta.js";
+import rehypeSave from "../src/rehype-save.js";
 import remarkMath from "remark-math";
 
-import * as prompt from "prompt";
+import prompt from "prompt";
 
 const projectRoot = path.resolve(__dirname, "..");
 const exampleDir = path.resolve(projectRoot, "examples/render/input");
diff --git a/scripts/debug-term.ts b/scripts/debug-term.ts
index 9901efa..0819028 100644
--- a/scripts/debug-term.ts
+++ b/scripts/debug-term.ts
@@ -1,7 +1,7 @@
 import { fromMarkdown } from "mdast-util-from-markdown";
 import { inspect } from "node:util";
-import { lumaTerm } from "../src/luma-term/micromark-extension";
-import { lumaTermFromMarkdown } from "../src/luma-term/from-markdown-extension";
+import { lumaTerm } from "../src/luma-term/micromark-extension.js";
+import { lumaTermFromMarkdown } from "../src/luma-term/from-markdown-extension.js";
 
 const buf = `
 # Hello
diff --git a/src/lib/__tests__/to-slug.spec.ts b/src/lib/__tests__/to-slug.spec.ts
index 35aec36..455dc54 100644
--- a/src/lib/__tests__/to-slug.spec.ts
+++ b/src/lib/__tests__/to-slug.spec.ts
@@ -1,4 +1,4 @@
-import { toSlug } from "../to-slug";
+import { toSlug } from "../to-slug.js";
 import { describe, expect, it } from "vitest";
 
 describe("toSlug", () => {
diff --git a/src/lib/term/__tests__/detect.spec.ts b/src/lib/term/__tests__/detect.spec.ts
index 584a30f..eda1994 100644
--- a/src/lib/term/__tests__/detect.spec.ts
+++ b/src/lib/term/__tests__/detect.spec.ts
@@ -1,4 +1,4 @@
-import { extractTerms } from "../detect";
+import { extractTerms } from "../detect.js";
 import { describe, expect, it } from "vitest";
 
 describe("extractTerms", () => {
diff --git a/src/luma-counter/from-markdown-extension.ts b/src/luma-counter/from-markdown-extension.ts
index ae87f5b..9599082 100644
--- a/src/luma-counter/from-markdown-extension.ts
+++ b/src/luma-counter/from-markdown-extension.ts
@@ -1,4 +1,4 @@
-import { type Extension as FromMarkdownExtension } from "mdast-util-from-markdown";
+import type { Extension as FromMarkdownExtension } from "mdast-util-from-markdown";
 
 export const lumaCounterFromMarkdown: FromMarkdownExtension = {
   enter: {
diff --git a/src/luma-save/from-markdown-extension.ts b/src/luma-save/from-markdown-extension.ts
index 3c1c973..bd77d73 100644
--- a/src/luma-save/from-markdown-extension.ts
+++ b/src/luma-save/from-markdown-extension.ts
@@ -1,4 +1,4 @@
-import { type Extension as FromMarkdownExtension } from "mdast-util-from-markdown";
+import type { Extension as FromMarkdownExtension } from "mdast-util-from-markdown";
 
 export const lumaSaveFromMarkdown: FromMarkdownExtension = {
   enter: {
diff --git a/src/luma-term/from-markdown-extension.ts b/src/luma-term/from-markdown-extension.ts
index 642bcbe..7ef1432 100644
--- a/src/luma-term/from-markdown-extension.ts
+++ b/src/luma-term/from-markdown-extension.ts
@@ -1,5 +1,5 @@
-import { type Extension as FromMarkdownExtension } from "mdast-util-from-markdown";
-import { lumaTermAttributes } from "./constants";
+import type { Extension as FromMarkdownExtension } from "mdast-util-from-markdown";
+import { lumaTermAttributes } from "./constants.js";
 
 export const lumaTermFromMarkdown: FromMarkdownExtension = {
   enter: {
diff --git a/src/rehype-add-slug.ts b/src/rehype-add-slug.ts
index 97a9641..115927e 100644
--- a/src/rehype-add-slug.ts
+++ b/src/rehype-add-slug.ts
@@ -1,8 +1,8 @@
 import { toText } from "hast-util-to-text";
-import { toSlug } from "./lib/to-slug";
-import { STEP_OVER, visit } from "./util/visit";
-import { estreeJsonParseOf } from "./util/estree-json-parse-of";
-import { Toc, TocHeading } from "./types";
+import { toSlug } from "./lib/to-slug.js";
+import { STEP_OVER, visit } from "./util/visit.js";
+import { estreeJsonParseOf } from "./util/estree-json-parse-of.js";
+import type { Toc, TocHeading } from "./types.js";
 import type { ElementContent } from "hast";
 
 type Root = import("hast").Root;
diff --git a/src/rehype-clean-internal.ts b/src/rehype-clean-internal.ts
index 3f4b30a..7d253fc 100644
--- a/src/rehype-clean-internal.ts
+++ b/src/rehype-clean-internal.ts
@@ -1,4 +1,4 @@
-import { DELETE, visit } from "./util/visit";
+import { DELETE, visit } from "./util/visit.js";
 
 type Root = import("hast").Root;
 
diff --git a/src/rehype-counter.ts b/src/rehype-counter.ts
index db74a67..844c335 100644
--- a/src/rehype-counter.ts
+++ b/src/rehype-counter.ts
@@ -1,9 +1,9 @@
 import { MdxJsxFlowElementHast } from "mdast-util-mdx-jsx";
-import { visit } from "./util/visit";
-import { getAttrByName } from "./util/util-mdast";
-import { estreeJsonParseOf } from "./util/estree-json-parse-of";
-import { lumaCounter } from "./luma-counter/micromark-extension";
-import { lumaCounterFromMarkdown } from "./luma-counter/from-markdown-extension";
+import { visit } from "./util/visit.js";
+import { getAttrByName } from "./util/util-mdast.js";
+import { estreeJsonParseOf } from "./util/estree-json-parse-of.js";
+import { lumaCounter } from "./luma-counter/micromark-extension.js";
+import { lumaCounterFromMarkdown } from "./luma-counter/from-markdown-extension.js";
 
 type Root = import("hast").Root;
 
diff --git a/src/rehype-debug.ts b/src/rehype-debug.ts
index b7c6346..0c87e74 100644
--- a/src/rehype-debug.ts
+++ b/src/rehype-debug.ts
@@ -1,4 +1,4 @@
-import { visit, STEP_OVER } from "./util/visit";
+import { visit, STEP_OVER } from "./util/visit.js";
 import { inspect } from "node:util";
 
 type Root = import("hast").Root;
diff --git a/src/rehype-katex.ts b/src/rehype-katex.ts
index a3da225..6fb04dd 100644
--- a/src/rehype-katex.ts
+++ b/src/rehype-katex.ts
@@ -4,16 +4,16 @@ import type {
 } from "mdast-util-mdx-jsx";
 import type { MdxFlowExpressionHast } from "mdast-util-mdx-expression";
 import type { Expression } from "estree";
-import { DELETE, REPLACE, STEP_OVER, visit } from "./util/visit";
+import { DELETE, REPLACE, STEP_OVER, visit } from "./util/visit.js";
 import { toText } from "hast-util-to-text";
-import { getAttrByName } from "./util/util-mdast";
-import { estreeDeclareSymbol } from "./util/rehype-katex/estree-declare-symbol";
-import { estreeResetCtx } from "./util/rehype-katex/estree-ctx-reset";
-import { estreeDeleteCtx } from "./util/rehype-katex/estree-ctx-delete";
-import { estreePushCtx } from "./util/rehype-katex/estree-ctx-push";
-import { estreeCtxValue } from "./util/rehype-katex/estree-ctx-value";
+import { getAttrByName } from "./util/util-mdast.js";
+import { estreeDeclareSymbol } from "./util/rehype-katex/estree-declare-symbol.js";
+import { estreeResetCtx } from "./util/rehype-katex/estree-ctx-reset.js";
+import { estreeDeleteCtx } from "./util/rehype-katex/estree-ctx-delete.js";
+import { estreePushCtx } from "./util/rehype-katex/estree-ctx-push.js";
+import { estreeCtxValue } from "./util/rehype-katex/estree-ctx-value.js";
 import type { Element } from "hast";
-import { getClasses } from "./util/get-classes";
+import { getClasses } from "./util/get-classes.js";
 
 type Root = import("hast").Root;
 
diff --git a/src/rehype-replace-text.ts b/src/rehype-replace-text.ts
index 74f57ca..9e86263 100644
--- a/src/rehype-replace-text.ts
+++ b/src/rehype-replace-text.ts
@@ -1,5 +1,5 @@
-import { replaceJapanesePunctuation } from "./lib/replace-japanese-punctuation";
-import { visit, STEP_OVER } from "./util/visit";
+import { replaceJapanesePunctuation } from "./lib/replace-japanese-punctuation.js";
+import { visit, STEP_OVER } from "./util/visit.js";
 
 type Root = import("hast").Root;
 
diff --git a/src/rehype-save.ts b/src/rehype-save.ts
index d2ca3cb..e6e1a64 100644
--- a/src/rehype-save.ts
+++ b/src/rehype-save.ts
@@ -1,11 +1,11 @@
-import { lumaSave } from "./luma-save/micromark-extension";
+import { lumaSave } from "./luma-save/micromark-extension.js";
 import type {
   MdxJsxFlowElement,
   MdxJsxFlowElementHast,
 } from "mdast-util-mdx-jsx";
-import { lumaSaveFromMarkdown } from "./luma-save/from-markdown-extension";
-import { DELETE, REPLACE, STEP_OVER, visit } from "./util/visit";
-import { estreeJsonParseOf } from "./util/estree-json-parse-of";
+import { lumaSaveFromMarkdown } from "./luma-save/from-markdown-extension.js";
+import { DELETE, REPLACE, STEP_OVER, visit } from "./util/visit.js";
+import { estreeJsonParseOf } from "./util/estree-json-parse-of.js";
 
 type Root = import("hast").Root;
 
diff --git a/src/rehype-wrap.ts b/src/rehype-wrap.ts
index 68ae638..97ab8c9 100644
--- a/src/rehype-wrap.ts
+++ b/src/rehype-wrap.ts
@@ -1,7 +1,7 @@
-import { EXIT, visit } from "./util/visit";
+import { EXIT, visit } from "./util/visit.js";
 import type { MdxJsxFlowElement } from "mdast-util-mdx-jsx";
-import { getAttrByName } from "./util/util-mdast";
-import { estreeJsonParseOf } from "./util/estree-json-parse-of";
+import { getAttrByName } from "./util/util-mdast.js";
+import { estreeJsonParseOf } from "./util/estree-json-parse-of.js";
 
 type Root = import("hast").Root;
 
diff --git a/src/remark-debug.ts b/src/remark-debug.ts
index 0d83448..ae5e8e2 100644
--- a/src/remark-debug.ts
+++ b/src/remark-debug.ts
@@ -1,4 +1,4 @@
-import { visit, STEP_OVER } from "./util/visit";
+import { visit, STEP_OVER } from "./util/visit.js";
 import { inspect } from "node:util";
 
 type Root = import("mdast").Root;
diff --git a/src/remark-meta.ts b/src/remark-meta.ts
index 9b575fc..a0cbfc5 100644
--- a/src/remark-meta.ts
+++ b/src/remark-meta.ts
@@ -1,5 +1,5 @@
-import { getMdastMeta } from "./util/util-mdast-meta";
-import { estreeJsonParseOf } from "./util/estree-json-parse-of";
+import { getMdastMeta } from "./util/util-mdast-meta.js";
+import { estreeJsonParseOf } from "./util/estree-json-parse-of.js";
 
 type Root = import("mdast").Root;
 
diff --git a/src/remark-term.ts b/src/remark-term.ts
index 73e1150..5dc5be0 100644
--- a/src/remark-term.ts
+++ b/src/remark-term.ts
@@ -1,13 +1,13 @@
 import type { MdxJsxFlowElement } from "mdast-util-mdx-jsx";
 
-import { lumaTerm } from "./luma-term/micromark-extension";
-import { lumaTermFromMarkdown } from "./luma-term/from-markdown-extension";
-import { getMdastMeta } from "./util/util-mdast-meta";
-import { mapIntersection } from "./lib/map-util";
-import { setAttr, getAttrByName } from "./util/util-mdast";
-import { lumaTermAttributes } from "./luma-term/constants";
-import { STEP_OVER, visit } from "./util/visit";
-import { estreeJsonParseOf } from "./util/estree-json-parse-of";
+import { lumaTerm } from "./luma-term/micromark-extension.js";
+import { lumaTermFromMarkdown } from "./luma-term/from-markdown-extension.js";
+import { getMdastMeta } from "./util/util-mdast-meta.js";
+import { mapIntersection } from "./lib/map-util.js";
+import { setAttr, getAttrByName } from "./util/util-mdast.js";
+import { lumaTermAttributes } from "./luma-term/constants.js";
+import { STEP_OVER, visit } from "./util/visit.js";
+import { estreeJsonParseOf } from "./util/estree-json-parse-of.js";
 
 type Root = import("mdast").Root;
 
diff --git a/src/util/estree-json-parse-of.ts b/src/util/estree-json-parse-of.ts
index 79aa157..d24a56d 100644
--- a/src/util/estree-json-parse-of.ts
+++ b/src/util/estree-json-parse-of.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 
 export const estreeJsonParseOf = (value: unknown): Program => {
   return {
diff --git a/src/util/rehype-katex/estree-ctx-delete.ts b/src/util/rehype-katex/estree-ctx-delete.ts
index 395c0e2..574ab5d 100644
--- a/src/util/rehype-katex/estree-ctx-delete.ts
+++ b/src/util/rehype-katex/estree-ctx-delete.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 
 export const estreeDeleteCtx = (varName: string): Program => {
   return {
diff --git a/src/util/rehype-katex/estree-ctx-push-const.ts b/src/util/rehype-katex/estree-ctx-push-const.ts
index 484747d..130088e 100644
--- a/src/util/rehype-katex/estree-ctx-push-const.ts
+++ b/src/util/rehype-katex/estree-ctx-push-const.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 
 export const estreePushCtxConst = (varName: string, v: string): Program => {
   return {
diff --git a/src/util/rehype-katex/estree-ctx-push.ts b/src/util/rehype-katex/estree-ctx-push.ts
index c856971..4ff0c58 100644
--- a/src/util/rehype-katex/estree-ctx-push.ts
+++ b/src/util/rehype-katex/estree-ctx-push.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 import type { Expression } from "estree";
 
 export const estreePushCtx = (varName: string, expr: Expression): Program => {
diff --git a/src/util/rehype-katex/estree-ctx-reset.ts b/src/util/rehype-katex/estree-ctx-reset.ts
index 81a4362..1467091 100644
--- a/src/util/rehype-katex/estree-ctx-reset.ts
+++ b/src/util/rehype-katex/estree-ctx-reset.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 
 export const estreeResetCtx = (varName: string): Program => {
   return {
diff --git a/src/util/rehype-katex/estree-ctx-value.ts b/src/util/rehype-katex/estree-ctx-value.ts
index fca1620..9d89048 100644
--- a/src/util/rehype-katex/estree-ctx-value.ts
+++ b/src/util/rehype-katex/estree-ctx-value.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 
 export const estreeCtxValue = (varName: string): Program => {
   return {
diff --git a/src/util/rehype-katex/estree-declare-symbol.ts b/src/util/rehype-katex/estree-declare-symbol.ts
index 0d57685..5db9d26 100644
--- a/src/util/rehype-katex/estree-declare-symbol.ts
+++ b/src/util/rehype-katex/estree-declare-symbol.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 
 export const estreeDeclareSymbol = (varName: string): Program => {
   return {
diff --git a/src/util/rehype-katex/estree-var.ts b/src/util/rehype-katex/estree-var.ts
index 29cae21..5bc2a11 100644
--- a/src/util/rehype-katex/estree-var.ts
+++ b/src/util/rehype-katex/estree-var.ts
@@ -1,4 +1,4 @@
-import type { Program } from "@mdx-js/mdx/lib/core";
+import type { Program } from "estree";
 
 export const estreeVar = (varName: string): Program => {
   return {
diff --git a/src/util/util-mdast-meta.ts b/src/util/util-mdast-meta.ts
index 2443ebb..18f1f1b 100644
--- a/src/util/util-mdast-meta.ts
+++ b/src/util/util-mdast-meta.ts
@@ -1,4 +1,4 @@
-import { visit, STEP_OVER } from "./visit";
+import { visit, STEP_OVER } from "./visit.js";
 import type { Node } from "unist";
 import * as YAML from "yaml";
 
diff --git a/tsconfig.json b/tsconfig.json
index d327041..046854f 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,8 +1,8 @@
 {
   "compilerOptions": {
     "strict": true,
-    "module": "ESNext",
-    "moduleResolution": "Node",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
     "skipLibCheck": true,
     "target": "ES2022",
     "outDir": "dist",