The best of Product for Engineers in 2025
Contents
2025 was a big year for this newsletter (and PostHog).
We published 28 posts that were read over 1M times.
We started the year at ~38k subscribers and ended it at over 100k.
PostHog launched error tracking, PostHog AI, LLM analytics, a fully revamped experiments experience, mobile session replay, an MCP server, a job board, Deskhog, our install wizard, a new website, and much more.
We also raised a Series D and Series E and are now at 159 people and hiring many more.
To wrap up 2025, we're rounding up the most noteworthy of our work this year.
Most popular posts
Collaboration sucks -
Charles CookCharles Cook‘s anti-collaboration manifesto was our most popular post of the year with 112,220 views, 167 shares, and a considerable amount of controversy.50 things we've learned about building successful products - A roundup of many lessons we've learned while building PostHog also made the front page of Hacker News, leading it to be our second most popular post.
32 things we've learned about building a startup that scales - Charles' reflections on culture, hiring, product, and marketing as PostHog has grown from 11 people to over 150 rounds out our top 3.
Lottie's favorite hedgehog
We're lucky to have Lottie's illustrations liven up nearly every edition of Product for Engineers. Of the dozens of hedgehogs she drew this year, here are her two favorites:
Underrated posts
Although we're proud of every post we published, not every one was a winner. Here are three that didn't get the attention we thought they deserved:
The deadline doom loop -
James HawkinsJames Hawkins's post against deadlines is still one we often reference internally and is basically the guide to how we do scheduling at PostHog (spoiler: we don't).WTF is activation and why should engineers care? - Activation is one of the product metrics we care the most about (and you should too). This post was a deep dive on how to do it.
Good taste makes great products - As everyone's worried about AI taking their jobs, one concept stood as a valiant guardian: taste.
Danilo CamposDanilo Campos's post on taste's importance and how to build it provides a much-needed guide.
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James' best tweet
Name a more iconic duo: James HawkinsJames Hawkins and quick calls.
Our favorite posts
Beyond being popular or unpopular, here were our favorite posts to work on:
Ian VanagasIan Vanagas - What engineers get wrong about communication - Communicating well is a mystical aspiration. I learned a lot about what that actually means (and how to make it happen) while writing this post.
Andy VandervellAndy Vandervell - Glue teams vs back-office teams - 
Michael MatlokaMichael Matloka is one of PostHog's most talented and delightful engineers. His post is a great example of the writing culture of PostHog at its best, and a great exploration of a subtle but important dilemma that faces every company sooner or later.- Charles CookCharles Cook - Non-obvious SEO advice for startups - It's marketing-y but I always appreciate Andy's SEO wisdom.
What we learned about writing a newsletter
We had the goal of “going weekly” multiple times this year without realizing we were basically repeatedly running into the good/fast/cheap tradeoff as blocker. To ship the quality of newsletters we want to ship weekly, we simply need more people.
Newsletters provide a secondary benefit of crystallizing what our team has already figured out. There is a lot of internal knowledge that we are able to solidify into a clear insight and share because of the newsletter.
Unfortunately, Substack as a platform continues to develop in a way that's misaligned with us. It focuses on creators with paid subscriptions, but this newsletter is free and always will be.
You can't predict which newsletters are going to do well or poorly. In another universe, “The deadline doom loop” is our most popular newsletter of the year and “Collaboration sucks” is a dud.
No matter what you do, you'll always be writing, editing, and tweaking up to the time you publish. Publishing consistently frees you from needing to make every post perfect.
Our founders IRL
It may surprise you, but our founders don't just live inside their computers. Here are their best talks from this year:
From Pivot Hell To $1.4 Billion Unicorn - A milestone for any founder: an interview on the YC Youtube channel.
How to Not Break Up With Your Co-Founder - Worth a click purely for the thumbnail. 💪
How to build a cult - James channeling his inner Adam Neumann or making salient points about startup branding. You'll have to click to find out…
Our team's favorite tools
Here are some less well known tools our team loves:
Atuin - The shell tool some “legitimately can't live without”. It solved remembering CLI commands for them.
Flox - Goodbye broken developer environments. We migrated this year and “it's worked exceptionally well for avoiding weird one off config issues.”
0github - A heatmap diff viewer for code reviews. The starting point for code reviews to discover sections that deserve real attention.
Orbstack - Basically our whole team has migrated over from Docker.
Mergiraf - “If you aren't using mergiraf to solve Git merge conflicts, you are missing out.”
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PostHog is an all-in-one developer platform for building successful products. We provide product analytics, web analytics, session replay, error tracking, feature flags, experiments, surveys, LLM analytics, data warehouse, CDP, and an AI product assistant to help debug your code, ship features faster, and keep all your usage and customer data in one stack.