Using Automation to Generate $300/mo in Passive Income

Hello! What's your background, and what are you working on?

Hi, my name is Ivan Delchev. I'm an entrepreneur and software engineer living in Switzerland. To stay up-to-date with technology and product trends, I try out new things and release them publicly to get real-world feedback.

One of my latest side projects is Hacker News Books, a service which searches Hacker News comments for links to books on Amazon, Safari Books, and O'Reilly, aggregates them, and then ranks them based on votes, karma, and other criteria.

My readers are a tech-savvy crowd who like to read books, and a lot of them subscribe to the weekly newsletter, which I consider one of the best ways for me to keep in touch with them.

Currently, Hacker News Books makes about $250-$350/month via Amazon Affiliates in the US, and this is the only way it is monetized. For me, it's very important that the side projects I release do not require supervision, and generate passive income. That's why I focus on automation and organic growth strategies.

What motivated you to get started with Hacker News Books?

There are many ways to learn and try new things, but I've found that what works best for me is to start something from scratch and treat it as a real product — designed for a particular audience, ready to scale, and, most importantly, released to the public. Only in this way can you see all the challenges and implications you might miss when simply coding for fun.

Release. Done is always better than perfect.


I am also an avid reader of Hacker News. The quality of stories and comments there is extremely high, which made me realize that, most likely, the books discussed there would be of high quality as well. And this is how the idea for Hacker News Books came to be.

What went into building the initial product?

After coming up with the idea, there were two very important things to validate:

  1. that there was enough good book content
  2. that people were interested in receiving those book lists

My background is in full-stack development and, to a smaller degree, DevOps, so grokking #1 above was relatively easy. It turned out there were between 30-50 books being discussed weekly, all high in quality and diverse in topic.

To take care of #2, I decided to bring the idea to the people that would be most interested in it — the Hacker News crowd itself. What I also needed was a way to stay in touch with the crowd, even after the initial hype. So I added a rather aggressive newsletter popup, which I'm not extremely fond of, but it simply works. (I've actually written a long post about it.)

You will always find someone to complain about it, but the majority of people either click it away if they aren't interested, or they give you their very valuable email address.

What made life easier on the tech side was the full adoption of Docker — from IDE integration to local development, staging, and even production. It's a real competitive advantage if you're an indie entrepreneur, as it saves you a lot of DevOps and setup, gives you a fast way to validate your idea with a prototype, and allows you to easily scale out if needed. I'm using Elastic Search for full-text search, and Python for the backend. I've integrated with Mailchimp and Amazon Affiliates APIs.

Developing the final product took less than 2 months, working on and off in the evenings.

How have you attracted users and grown Hacker News Books?

I submitted the story about Hacker News Books to HN on Friday, August 26. Timing was based on this research and the fact that, according to SimilarWeb, 38% of the users on HN come from the US. So the timing had to make sense for those time zones.

From there things went really fast, and I landed the number one story on Hacker News. That day, my site got 45,000 eyeballs and the newsletter picked up more than 600 subscribers. And over the five days that followed, I collected a solid $1,000 in Amazon Affiliate fees.

The Amazon Associates referral program is straightforward — if you refer a user to Amazon and they make a purchase in the next 24 hours, you get a cut as soon as their purchase ships.

Depending on the product, the referral rate starts at about 3%, and quickly grows to 7-8% if enough purchases are made in a month. Each month, the referral rate resets to the base. There are also fixed rewards — so-called bounties — which are applied when someone registers for a service from Amazon, such as Audible or Amazon Prime.

What this means is that larger numbers of referrals per month are rewarded better — first from the increased volumes, and second from the increased rates.

One thing is important to note: merely getting access to the referral program does not mean your website has been approved. The approval in my case came a week after the first referrals were made. I believe the volume in the first days is important, since some people have written me to ask how I got accepted, while their blogs, for some reason, did not.

To grow the audience further, I've tried Facebook ads, but they turned out to be too costly — not enough subscriptions to have a reasonable ROI.

Don't be afraid to fail — every failure prepares you better for the next attempt.


What worked really well were cross promotions with publishers and book authors. Nowadays, everyone's interested in getting as much visibility as possible, and working with others is a great way to achieve that.

The downside is that it requires a lot of manual work and mail writing, so I focused on growing traffic organically. I segmented books based on topics, created thematic lists, and added search, which has doubled organic traffic in the past months.

What's your advice for indie hackers who are just starting out?

Lessons learned from building Hacker News Books and other stuff:

  • Release. Done is always better than perfect.
  • Catch those emails and stay in touch with your users.
  • Use technology that allows you to move fast but still scale out if needed.
  • Don't be afraid to fail — every failure prepares you better for the next attempt.

Where can we go to learn more?

To learn more about Hacker News Books, visit the website and the blog, and subscribe to the newsletter of course!

Also, do not hesitate to simply drop me a line. I promise to write back. Let me know what you think, and I'll be happy to answer any questions!

Good luck with your indie hacking!

Ivan Delchev

Want to build your own business like Hacker News Books?

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  1. 7

    Hi. Do you use HN apis or html scraping to get your results?

  2. 3

    How much of your traffic is organic ? Did you implement a strategy to optimize your seo. I know that google doesn't like it if it's a website filled up with affiliate links.

  3. 3

    The newsletter is the killer feature here. You only need to get someone to visit the site once and sign up for the newsletter. From then, your content is pushed to them.

    Nice implementation.

    1. 2

      Thanks! I also think that people underestimate the importance of a newsletter. It's the single most powerful marketing channel I've found so far.

      1. 1

        That's true! Conversion rate is higher rather than using social media as a marketing channel.

  4. 2

    i wonder how HNBooks is doing a year after launch? please come back to report!

  5. 1

    Hello, saw your site! Good job. What did you use to build your front-end? Bootstrap? React? I am trying to build my own site but it has very basic front-end and I want to improve it.

  6. 1

    A lot of people got in touch to ask if the service is for sale or if I am looking for collaboration so I am posting here to clarify.

    1. If you have a reasonable offer and an idea how to grow the service just get in touch and we can talk.

    2. If you are interested to help with your good marketing skills you can also drop me a line and we can come up with something

  7. 1
  8. 1

    This was one of the stories that inspired me to create my project about books ( I made it fast and deployed it, it was just a simple page but it got some visits and attention, then I learn what visitors wanted and started to add new features, pages, articles, and sections. But this story helped me to make the first step. thanks

  9. 1

    Smart and easy. Great implementation! Thanks for sharing!

  10. 1

    Really smart idea. Congrats on the success!

  11. 1

    Ivan, great interview! I was in amazon affiliates before, but I only made 67 cents in commissions so they ended my account. It's a challenging program.

    How did you reach out to book publishers and authors or did they find you?

    1. 2

      I tried reaching out and proposed a cross-promotion directly. It's a win-win situation, although I must say it does not scale much - involves mail writing, preparing content, agreeing on how they'd mention you etc.

  12. 1

    What would you say are some strategies to increase the chances of getting approved for Amazon Affiliates? Should one build up a good amount of site traffic first, and then try to get approved?

    1. 1

      I can't say that for sure, but certainly getting a spike of traffic after launch helps. I got the approval about a week after launch (with more than 800 purchases in a couple of days).

      1. 1

        Did you lose out on the referrals made before you were approved?

        1. 1

          No, they remained

  13. 1

    Hi Ivan, very good idea!

    Thinking about the tech side, how do you find books in Hacker News comments?

    1. 1

      I process all links and extract those that point to Amazon, Safari or O'Reilly. Afterwards I verify that it is indeed a book page - e.g. via the Amazon Product API or metadata on the page.