Companion to The ripple you cannot see, the earlier piece this builds on.

The folder is called claudearchive. It sits on my G drive, gets backed up to H every night, snapshots itself on Sundays, and contains roughly a year of how I have been thinking. It exists because I built the thing that fills it. The thing that fills it exists because nothing else was going to.

I work in digital. I have done for fifteen years. I think in systems and the absence of one is loud to me. The thing in the folder is called Mimer. A hundred and ten tests across twenty-one categories. One third-party dependency. Pydantic enforces the shape, unittest catches the regressions, the rest is stdlib. It is the closest thing I have ever had to a real personal assistant, and the fact that I had to build it is what this piece is about.

The shape of what is missing

If you want your Claude history out of Anthropic's hands and into yours, you can have it. You go to settings, you click a button, an email arrives, and a JSON file lands in your downloads folder. It contains your conversations. Most of them, in some form. The schema shifts between releases, which is a detail I would not have noticed if I were not running diffs. I am, so I have.

The format changed under me earlier this week. The single projects.json file the export had used since I started running it became a per-project directory, one JSON per project, repackaged without warning. No changelog entry, no email, no deprecation notice. I shipped a fix yesterday.

There is also a defect in what does ship. Every chat in every project arrives with its project linkage stripped, project set to null in the file, regardless of which project it lived in inside the UI. I reported this a week ago via the thumbs-down channel and a follow-up email. Status open.

The export is not nothing. It is a snapshot. A photograph of the conversations as they exist on a particular Tuesday. What it is not is an interface. There is no append, no subscribe, no scoped read. You cannot pipe it forward. You can download it again on Wednesday and try to work out what changed. That is the shape of the access.

Mimer is what fills the gap between the photograph and the room.

What it does

Every time the export refreshes, Mimer ingests it, diffs it against the previous run via a SHA256 manifest, scrubs secrets out of new conversations through fifteen redaction patterns, and writes the result into the archive. The archive is one folder of redacted JSON files for chats, project metadata and docs under their own subtree, Anthropic's cross-chat memory carried separately, and a unified CSV index that lets me search across all of them. The hundred and ten tests are not a flex. They are what happens when the format you depend on changes shape under you for the third time and you decide you are done being surprised by it.

On the desktop where I built it, Claude reads the archive directly through the local filesystem MCP. It can search the index, pull whole chats, work across the project boundaries the product itself enforces. On phone and on browser claude.ai it cannot, because that MCP is a local process and the cloud does not reach into it. The next move is to put the archive into a Google Drive folder, where Drive's own MCP carries it across to mobile and browser. So the local tool I built to work around the missing API needs a cloud tool I do not own to work around its own locality. That is the shape.

It is not a product. I am not going to ship it. It solves my problem, on my machine, in a form I control. That is the bit that matters.

The well

I called it Mimer because of Mímir. The Norse well at one of the roots of the world tree, guarded by a wise giant. Odin gave an eye for one drink from it. The detail I keep coming back to is that the well does not produce wisdom. It holds it. You bring the question, you accept the cost, you receive what was already there.

The archive does the same job. Claude is what drinks. Mimer is what is drunk from. Without the well, the model is as smart as it was on the day it was trained, plus whatever I can fit into a single window. With the well, on the desktop where MCP can reach, it can find anything I wrote across a year. The only constraint is freshness, and freshness is bounded by the last time I clicked the export button.

The privacy word

The reason given, when one is given, is privacy. I am not going to litigate that here. I wrote a piece in April about the same word doing different jobs depending on which way the request flows, and the part that matters for this one is short. When the platform wants to defend something, the word narrows. When the user wants something, the word widens. Same word, different jobs.

There are real concerns mixed in with the convenient ones. Conversations are sensitive. They contain other people. A scoped portability API is harder to ship safely than a one-shot zip. Some of the cost is genuine. But the framing where the cost is presented as privacy, full stop, end of conversation, is a framing. The thing it protects is not only my data. It is also the architecture in which I cannot easily leave with it.
I am not angry about this. I notice it.

Asked ChatGPT itself, earlier this week.

The thing underneath

What I keep coming back to is not the API I do not have. It is that most people cannot build Mimer.

Writing a hundred and ten tests around an export format that drifts is not a reasonable expectation to put on the median user, and it should not be the price of having a memory. The argument I most often hear, when this comes up, is that most people do not want this complexity. They want a simple chat. The chat resets, that is fine, that is what the product is. I think this is true for some people. I do not think it is true forever, and I do not think it is true once the kind of continuity I am describing here becomes visibly available to the people who can build their way to it.

What is being privatised in the name of privacy is the assistant itself. People who think in systems get one that knows what they have been working on. Everyone else gets a window that resets. The gap between those two groups is going to keep getting wider, and it is going to keep being framed as protective of the people on the wrong side of it.

I do not have a clean answer to that. The well I dug, I dug for myself. Mimer is one person's response to one person's problem. It does not solve the underlying thing. It is one ripple in a different direction.

The well, the eye

The Mímir story is usually told as a sacrifice story. Odin gave an eye for wisdom. There is a quieter version of the same story, less told, which is about preparation. The wisdom was already there. The eye was the cost of admission. The well existed first.

The conversations are mine. The model knows me by them. The thing I built sits between, on my disk, in a form I can read, scrubbed of the parts I did not want kept, indexed in a way that lets me find myself again. I had to dig for it. I would have preferred not to. The fact that I had to is the piece. The fact that I now have it is why I am not finishing it angry. I built something by Jakob, for Jakob. It will keep working until it doesn't. Then I will fix it. Probably via a Zapier... or an eye.