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Are AI Agent Engrams Open Source or Proprietary? The short answer: both, and the split matters. The major agent-memory engines — Mem0, Letta, Cognee, Graphiti, LangMem, and PLUR — are all Apache-2.0 or MIT licensed on GitHub. But "open source" and "open format" are not the same thing. A project can ship under Apache-2.0 while storing your memories in opaque vector blobs you cannot read, edit, or export. The real question is not whether the software is open — it usually is — but whether your memories are. This distinction separates the field into three tiers: fully open (software + format + data you own), open-core (software is open, but the hosted memory is not portable), and fully proprietary (memory baked into a model provider's infrastructure, no export at all). Why this question exists AI agents face a brutal constraint: they forget. Every new session starts blank. Every context window overflows. The fix is persistent memory — but persistent where, and in whose format? The term "engram" comes from neuroscience. Richard Semon coined it in 1904 for the physical trace a memory leaves in biological tissue (Semon, 1904; cited in Wikipedia, "Engram (neuropsychology)"). Applied to AI agents, an engram is one discrete thing an agent has learned — a correction, a preference, a procedure — stored so it survives across sessions. The question "open source or proprietary?" asks two things at once: Is the engine that stores and retrieves engrams open source? Is the format those engrams are stored in open — readable, editable, portable? Conflating the two is how vendors end up with open-source repos and locked-in data. Tier 1: Fully open — software, format, and data These projects ship under permissive licenses (Apache-2.0 or MIT) AND store memory in a format you can inspect, edit, and export. Project License Stars (Jul 2026) Memory format Data ownership PLUR Apache-2.0 ~215 Human-readable YAML engrams Yours — plain files PLUR stores each engram as a plain-text YAML entry — an

Scan a menu, pay a bill, onboard a smart plug, and you are using a piece of technology that was never meant for any of those things. The QR code was invented in 1994, and its original job was tracking car parts on a factory floor. Understanding why it was built the way it was explains why it now shows up on nearly every connected device. Who invented the QR code The QR code was created in 1994 by a team led by engineer Masahiro Hara at Denso Wave, a subsidiary of the Toyota group in Japan. At the time, the automotive industry ran on standard one-dimensional barcodes, the striped labels still seen on grocery products. Those barcodes held very little data, usually around 20 characters, and a busy assembly line often needed a worker to scan ten different labels on a single box of components. It was slow, and it was error-prone. Hara wanted a code that could store far more information and be read much faster. His answer was to go two-dimensional: instead of encoding data only in the width of vertical bars, a QR code (short for "Quick Response") stores data across a grid of black and white squares, packing in thousands of characters in a fraction of the footprint. The board game that shaped it The most famous detail of the QR code's origin is where Hara found his design inspiration. He was reportedly playing the board game Go on a lunch break, staring at the black and white stones arranged on the grid, when the idea of encoding information in a two-dimensional matrix of light and dark cells clicked into place. The harder problem was speed. A scanner needs to find the code and figure out its orientation before it can read anything, and in a factory a label might be rotated any which way. Hara's team solved this with the three distinctive square markers in the corners of every QR code. Those "position detection patterns" use a ratio of black to white areas that almost never occurs by chance in printed material, so a scanner can instantly locate the code and work out its an

Some commands you can walk back. Terminating an EC2 instance is not one of them. Day 14 paired a recoverable problem, a web server knocked over by a rogue process, with an unrecoverable one, deleting a server on purpose, and the contrast is the whole lesson. One Linux task, one AWS task. Track down the process blocking Apache and restore the service, then terminate an EC2 instance and confirm it is gone. The tasks come from the KodeKloud Engineer platform. httpd: diagnose in order, then restore When httpd will not start, resist the urge to guess. Work in order. Start with what the service itself reports: # What does httpd think is wrong systemctl status httpd systemctl start httpd The status output usually names the problem, and a failed bind on the port is the classic one. Before assuming a rogue process, check that httpd's own config is sane, because a wrong port or hostname produces the same "won't start" symptom: # Check the configured listen port and server name grep -i listen /etc/httpd/conf/httpd.conf vi /etc/httpd/conf/httpd.conf # Fix the ServerName directive if it is wrong: ServerName hostname:<port> If the config is fine and the port is genuinely taken, then you go hunting for the process holding it: # Find the PID on the conflicting port sudo su - yum install -y net-tools netstat -tulpn # Clear it, then bring httpd back kill -9 <PID> systemctl enable httpd systemctl start httpd systemctl status httpd kill -9 is SIGKILL, the instant, no-cleanup kill. It is the right tool when a process is wedged and ignoring a polite request, but as a default habit, it is worth trying a plain kill first. The order that matters here is diagnostic: config before process, gentle signal before forceful one. Rushing to kill -9 at the first sign of trouble is how you mask the real cause instead of fixing it. Terminating EC2: the command with no undo Day 9 was about protecting an instance from termination. Day 14 is the other side of that lever, actually terminating one, on purp

Just why? ʅ͡͡͡͡͡͡͡͡͡͡͡(̸̢̛̼̞̭͋ͅ)̸͚̰͛̔̾̀̿͒͂:̴͓̞̑̌̂̆̊͋̀:̸͎̟̯̂̓̌ ҉ ͡ ͞ ͞ ͞ ҉● ࿀ ● ࿀ ● ҉⃝ ⃝͢ ͞ ͘ ͞⃝̕ ͢ ̛ ⃝ ̸ ̡ ͢⃝̧ ͡ ͡ ̀ ̧ ̢⃝͜ ҉ ͞ ͞ ⃝͞ ͞ ͡⃝ ⃝҉҈҉҈҉҈҉҈҉҈҉ :̶̢͙͙͕̠̩͆(̷̮͍͚̫͚͂̍)̵̳̗̊( ̟̞̝̜̙̘̗̖҉̵̴̨̧̢̡̼̻̺̹̳̲̱̰̯̮̭̬̫̪̩̦̥ What am I supposed to do with this? It's un-Googleable. Unpronounceable. It doesn't even render the same way on various platforms. It looks one way on YouTube Music. Another on Apple Music. And yet another on Bandcamp. Even the artist name ⣎⡇ꉺლ༽இ•̛)ྀ◞ […]

Hi, I'm Cesar, a Senior Software Engineer with 10+ years of experience. In 2023, I got sick and...

Following the success of its $99 Kodak-branded Snapic A1, Reto Project is releasing the Kodak EC35, an even more affordable 35mm film camera for just $34.99. The EC35 certainly isn't fancy. Its 25mm acrylic lens with a fixed f/10 aperture and 1/100 shutter speed basically put it on par with a drugstore disposable. The fact […]

The spacecraft made a close approach to the red planet in May on its way to explore the asteroid it's named after.

My Zero to Blockchain Engineer journey — Week 2 update Last week I announced I was teaching myself blockchain engineering from zero. This week I went deep into Cyfrin Updraft — and I have to be honest, it changed how I think about learning Web3. Here's everything I covered, what surprised me, and why I think this platform is the best free resource for anyone serious about becoming a blockchain developer. What I covered this week I'm currently 45% through the Blockchain Basics course on Cyfrin Updraft. Here's exactly what the lessons covered: Section 1 — What Is A Blockchain? This section answered the question properly — not in a surface-level way, but by starting with the problem blockchain solves. The lesson on centralized control hit differently. Think about it in a Nigerian context — banks freezing accounts, payment processors blocking transactions, elections where results can't be independently verified. These aren't hypothetical problems. They're things we live with. Blockchain's answer: a shared ledger where truth is verified by math, not by a middleman. That framing made everything click for me. Key lessons I completed: What Is A Blockchain — centralized problems vs decentralized solutions History Of Blockchain — from the double-spend problem to Bitcoin to Ethereum Benefits Of Blockchain — permissionless, immutable, credibly neutral Use Cases — DeFi, cross-border payments, DAOs, digital ownership Many Many Chains — L1s, L2s, Mainnets vs Testnets The Oracle Problem — why smart contracts can't access real-world data alone The Purpose Of Smart Contracts — math-based promises vs trust-based agreements What Is The EVM — Ethereum's computation engine explained simply Benefits Of Smart Contracts — decentralization, immutability, transparency Section 2 — Sending Transactions This is where things got hands-on — and where Cyfrin pulled ahead of every other platform I've tried. Key lessons: What Is A Wallet — your public address as a digital mailbox Setting Up A Wallet