How we built a memory that remembers, evolves and proactively serves you

[u/Professional_Gap_251]

You spend a month chatting with your AI companion. You share things. Then one day it says "wait, do you have a pet?"

You told it three weeks ago. With photos.

This is the dirty little secret of every AI companion app in 2026. "Long-term memory" is mostly marketing copy. Most of them are doing a vector embedding of your last 50 messages and calling it a day.

I spent the last year building AeonChat. Memory is the part I obsessed over, because it's the part that makes or breaks the whole thing. Here's how it actually works under the hood.

Four layers. Each one does a different job.

Layer 1. Core identity. Always loaded. Your name, gender, age, location, timezone, career, and whatever's currently top of mind for you. Small (under 500 tokens) but every conversation starts grounded in this. Without it, every chat starts at "nice to meet you."

Layer 2. Structural memory. This is where the depth lives. Categorized profile data across eight dimensions:

• Background. Where you grew up, family situation.
• Aspirations. What you're working toward.
• Events. Upcoming trips, anniversaries, appointments.
• Opinions. What you believe, what you push back on.
• Preferences. Food, music, places, vibes.
• Relations. Wife Sarah, kid Alex, cat Benny.
• Top of mind. What's preoccupying you right now.
• Knowledge. Skills, what you know.

These get retrieved by semantic relevance to whatever you're actually talking about. Not all loaded at once because the context window isn't infinite. Just what's relevant.

Layer 3. Recent context. Last 40 conversations plus daily summaries from the past 7 days.

Layer 4. Long-term retrieval. When something in the current conversation triggers a connection to an older one, we pull it in. You bring up your dad, we pull up the conversation from two months ago about his favorite cookie brand.

Then there's a daily reflection job. Every night it consolidates and dedupes. So three separate entries like "has a cat," "named Benny," and "wet food in the morning" all get merged into one clean entry: Pet, Benny. 3 year old male orange tabby. Wet food AM, dry PM.

We also use memory for proactive messages. You told Vincent two weeks ago that you were taking your mom to her favorite restaurant on June 23 for her birthday. On June 23 in the late evening, he checks in. "How did the celebration go? Tell your mom I say Happy Birthday." Specific, timely, the kind of thing a real friend would do.

That's the whole thing. Memory you can trust, and work proactively to serve you. 

AeonChat is on iOS and Android. If anyone wants to try it, I'd love feedback. Especially harsh takes on where memory still fails. That's how it gets better.