Hindsight Is the Fastest-Growing Open-Source AI Memory Project Ever | Hindsight

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Hindsight — the agent memory that learns — is the fastest-growing open-source agent-memory project ever. This post lays out the evidence: our own analysis of GitHub's per-star data, and independent confirmation from two third parties who have no stake in the claim.

First, a word about why "fastest-growing" is harder to prove than it sounds — because the most obvious way to measure it is also the most misleading.

Go looking for AI memory projects on GitHub and you'll find one that appears to tower over everything else: north of 50,000 stars, accumulated in roughly two months. Case closed? Not quite. GitHub records a timestamp on every star, and when you pull them, that project's story falls apart. The bulk of its stars — tens of thousands of them — arrived within a few days of the repository being created, including more than 16,000 in a single day , before it had any audience at all. Real projects don't grow like that. Stars, it turns out, can be purchased, and a vertical wall of them on a brand-new repo is exactly what a purchase looks like.

So raw counts alone prove nothing. To make this claim honestly, we need measures that reflect real developers making a real choice — and that's exactly what holds up under every one we apply.

Start simple: who gains stars fastest?​

The simplest honest measure is total stars divided by how long a project has existed. Here's every major open-source agent-memory project — the legitimately-grown ones — by that number.

ProjectStarsAgeStars/day (lifetime avg)Hindsight 16,035 7.3 mo 72.2 Mem058,16835.6 mo53.6Graphiti27,21322.0 mo40.7Supermemory26,30327.3 mo31.6Letta / MemGPT23,22631.9 mo23.9Cognee17,74033.7 mo17.3Memobase2,74721.2 mo4.3Zep4,65437.4 mo4.1<br>Hindsight has the highest star velocity in the category — ahead of Mem0, which went on to become the largest agent-memory project on GitHub, and more than double Supermemory's pace. And it's doing it while being three to five times younger than everything else on the list. That's a promising first answer. But it's not yet a careful one.

The harder question: are we comparing fairly?​

A lifetime average can flatter a young project. Viral repositories tend to earn most of their stars in an early burst and then coast, so a project that's been around three years carries a long, slow tail that drags its average down. Measure Hindsight's seven hot months against Mem0's three-year average and you might be comparing a sprint to a marathon's pace — not a fair fight in either direction.

The honest way to settle it is to compare every project at the same point in its life. The same per-star timestamps that exposed the bought-star project let us reconstruct exactly how many stars each project had when it was the age Hindsight is today — 222 days.

ProjectStars at day 222Stars todayHindsight 16,035 16,035Letta / MemGPT9,69623,226Mem06,94258,168Supermemory6,38926,303Graphiti2,38327,213Zep1,5054,654Cognee34417,740<br>This is where the answer sharpens. At the same age, Hindsight has 1.6× the stars of the next-fastest project — Letta, which launched as the viral MemGPT — and 2.3× Mem0's . Mem0 eventually reached 57,000 stars, but at the seven-month mark where Hindsight stands today, it had fewer than 7,000. Every project in the category had a smaller audience at this age than Hindsight does now. There's no early spike hiding underneath the average. This is the spike — and it's the biggest one the category has produced through real adoption.

A project still accelerating, not coasting​

It would be easy to assume Hindsight only squeaked ahead in the final weeks. The month-by-month numbers say the opposite. Here is the cumulative star count for each project at 30-day intervals from the day its repository was created.

Day306090120150180210222Hindsight 28421,1911,9216,42611,17515,04216,035Letta / MemGPT5,6186,3446,8147,3507,6528,0519,2779,696Mem03,3823,6624,7615,2935,5915,7796,7236,942Supermemory02,2962,7382,9493,8535,2186,1816,389<br>Hindsight didn't lead from day one — and that's the most encouraging part of the picture. For the first four months it was a sleeper, under 2,000 stars while Letta and Mem0 sat comfortably ahead. Then, between day 120 and day 222, it added more than 14,000 stars in about 100 days — a sustained run of roughly 150 stars a day at its peak . That's the steepest stretch of organic growth the category has recorded, and the curve hasn't bent back down. While its competitors had already flattened at this age, Hindsight is still climbing.

And note the contrast in shape. The bought-star project's growth was a single vertical wall in week one. Hindsight's is a months-long ramp that gets steeper as more people use it — the signature of real word-of-mouth, not a one-time transaction. That inflection tracks with the moment production deployments...