How to Add Comments To Your GatsbyJS Blog In Less Than 10 Minutes

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In this quick article, you'll kearn how to add comments to your GatsbyJS Blog in less than 10 minutes using Utterances. Which is a free 🚀, no-ads 🚫, and open-sourced 🙌 solution for implementing comments using the GitHub Issues Search API. We'll create a new gatsbyjs blog and will add the capability to add comments to it. Fun Fact: Scroll to the bottom of this post. And you'll find the same implementation for the comments that I'm teaching you in this article

Cat typing fast gif


If you've a blog or website where you share your thoughts, tutorials, or articles etc, it is most likely that your intent is to share knowledge or your thoughts with an audience and you'd want to get their feedback on what you share. For that, implementing comments on your posts is a really good idea to gather feedback. Now, there are many ways to do that. But if you're a developer, or your audience is mainly folks who might have an account on GitHub, this article is for you.

For you gif

Let's do it!

Creating the GatsbyJS Blog project

We'll begin with creating a new project in our local machine. I'm supposing that you being a developer already has NodeJS installed in your machine. We'll start with creating a gatsbyjs project using the blog starter.

Choose a folder in your machine where you'd want to create this project, then run the following command in your command prompt/terminal after navigating to the folder:

npx gatsby new blog-with-comments

Now navigate to the folder and start the development server by using the following commands:

cd blog-with-comments

npm run develop

Navigate to http://localhost:8000 and you should now see the app working as follows:

Gatsby Starter Blog image

Creating the GitHub repository for the project

Go to your GitHub account and create a new repository as follows:

Gatsby Starter Blog image

No need to create any Readme or license file when you create this repository. Once done, go back to your project and add the new repository's origin to your git remote as follows:

git remote add origin <YOUR_REPOSITORY_URL>

Then push your code to your repository as follows:

git branch -M main
git remote add origin <YOUR_REPOSITORY_URL>
git push -u origin main

Installing the Utterances app for the GitHub repository

Now install the Utterances app into your newly created repository. I'd suggest using the "Only select repositories" option and specifically selecting your target repository within your GitHub space.

Implementing the Comments component to use the Utterances app

Once done, open the GatsbyJs project in your favorite editor. I personally use VSCode these days. Create a new file under the src/components folder named Comments.js and add the following code to it:

import React, { useEffect } from 'react'
const Comments = ({ issueTerm }) => {
  const commentsUUID = `comments_${issueTerm}`
  useEffect(() => {
    let anchor
    const theme = 'github-light' // you could choose other themes too
    const script = document.createElement('script')
    anchor = document.getElementById(commentsUUID)
    script.setAttribute('src', '')
    script.setAttribute('crossorigin', 'anonymous')
    script.setAttribute('async', true)
    script.setAttribute('repo', 'YOUR_GITHUB_USERNAME/YOUR_REPOSITORY_NAME')
    script.setAttribute('issue-term', issueTerm)
    script.setAttribute('theme', theme)
    return () => {
      anchor.innerHTML = ''
  return (
      <div id={commentsUUID} className="post-comments" className="relative">
        <div className="utterances-frame"></div>

export default Comments

Make sure to put the correct github username and the github repository as specified in the code above. Once done, add the Comments component in the src/templates/blog-post.js file as follows:

import * as React from 'react'
import { Link, graphql } from 'gatsby'

import Bio from '../components/bio'
import Layout from '../components/layout'
import Seo from '../components/seo'
import Comments from '../components/Comments'

const BlogPostTemplate = ({ data, location }) => {
  const post = data.markdownRemark
  const siteTitle = || `Title`
  const { previous, next } = data

  return (
    <Layout location={location} title={siteTitle}>
        description={post.frontmatter.description || post.excerpt}
      <article className="blog-post" itemScope itemType="">
          <h1 itemProp="headline">{post.frontmatter.title}</h1>
        <section dangerouslySetInnerHTML={{ __html: post.html }} itemProp="articleBody" />
        <Comments issueTerm={post.fields.slug} />
        <hr />
          <Bio />
      <nav className="blog-post-nav">
        <ul className="flex flex-wrape space-between p-0">
            {previous && (
              <Link to={previous.fields.slug} rel="prev">
            {next && (
              <Link to={next.fields.slug} rel="next">
                {next.frontmatter.title}              </Link>

export default BlogPostTemplate

export const pageQuery = graphql`
  query BlogPostBySlug(
    $id: String!
    $previousPostId: String
    $nextPostId: String
  ) {
    site {
      siteMetadata {
    markdownRemark(id: { eq: $id }) {
      excerpt(pruneLength: 160)
      fields {
      frontmatter {
        date(formatString: "MMMM DD, YYYY")
    previous: markdownRemark(id: { eq: $previousPostId }) {...}
    next: markdownRemark(id: { eq: $nextPostId }) {...}

Now navigate to http://localhost:8000 and click on any blog post. Scroll down and at the bottom, you should be able to see the comments widget as follows:

Comments widget image

And boom! 😄 You now have the capability to add comments to all your blog posts. Click the "Sign in with GitHub" button and try adding a comment. What's great is that the comment box supports markdown. Which means people can also add code snippets to their comments using the syntax highlighting etc.

CSample comment image

What's amazing is that the Utterances app will automatically generate a new GitHub issue for each post someone comments on.

GitHib Issue created for comments image

And if you wanted to moderate the comments, you can simply go to the GitHub issue and do that.


I found the Utterances app quite handy as I've been thinking about the easiest way to add comments to my blog for the developer community. I could go with creating my own comments and likes system using something like Firebase. But that's just too much work and I'd rather spend my time creating more content for you folks than re-inventing the wheel when there are already amazing and open-source solutions available like this.

Let me know in the comments if you found this article useful. Also, find my socials below to connect with me. Don't forget to share this article with your friends and as always, Happy coding!🎉

Would rather see a video tutorial? I got you covered 👌
Watch it below 👇