A good two weeks ago the Nasdaq — the index of the world’s biggest IT companies — properly tanked. You may have caught it. The reason: Claude Opus 4.6. While Wall Street fell into panic, many AI enthusiasts sat down at their computers and wondered: what can we do with this? What came out of it are programs of your own, for which you have so far paid a subscription — and which now run locally on your own computer.
That is exactly what I did in the last 24 hours as well. With Opus 4.6 in combination with Claude Code, I built my own Trello, created my own graphics program and — above all — my own CRM. Everything runs locally on my computer. I can adapt it however I like. And the lovely part: the data stays with me.
Note (as of July 2026): This article was written in February 2026 — back then, Opus 4.6 was the current model. Anthropic now lists Opus 4.6 as Legacy; current is Claude Opus 4.8. Everything you read here works with 4.8 just the same — only better. Which version makes sense for you is covered in the very next section.
Which Claude Opus version is current?
If you are landing here today, that is probably your first question. Here is the overview from Anthropic’s official documentation, as of July 2026:
| Version | Status | Knowledge cutoff | Price per million tokens |
|---|---|---|---|
| Opus 4.8 | current | January 2026 | $5 / $25 |
| Opus 4.7 | Legacy | January 2026 | $5 / $25 |
| Opus 4.6 | Legacy | May 2025 | $5 / $25 |
| Opus 4.5 | Legacy | May 2025 | $5 / $25 |
| Opus 4.1 | shut down on 5 Aug 2026 | January 2025 | $15 / $75 |
That makes the answer unambiguous: Take Opus 4.8. It costs exactly the same as 4.6 but has a knowledge cutoff eight months fresher — January 2026 instead of May 2025. There is currently no argument in favour of an older Opus version.
If you want to know how Opus 4.8 fares against Anthropic’s flagship model, I have compared that here: Claude Fable 5 vs. Opus 4.8 and 4.6.
What changed with Opus 4.6
Before I show you what I built, two important notes on the setup:
- I work with the Claude app — downloaded onto the computer once. On my Mac, Cowork is automatically enabled with it. On a Windows machine you have to unlock that once in developer mode, then you will see Cowork too.
- You do not need an expensive plan. I am currently on the Max plan — but only because I built so much with Claude recently that my allowance was used up. For a year and a half I worked with Claude for €18 a month. You can do all of this on the Pro version as well.
And one more thing up front: I am not a techie. I talk to Claude Code the way words come naturally to me — and I get to these results.
Project 1: my own Trello board — in 20 minutes
My “taskboard” starts with a double-click via its own icon on my desktop — Claude created that for me too. It looks like Trello and works like Trello: I create lists, cards within the lists, I describe and update them, move them back and forth. I can create several boards, give them colours and names — and if I want a calendar view on top: no problem.
My first prompt was as simple as it gets:
“Build me a simple dashboard, similar to Trello, where I can move tasks back and forth, where I can describe and update the cards. It should look like Trello and have the same functions.”
Claude Code then looked for itself at which skills it needed — for the view design, for instance — and created its own task lists. You can stay seated and watch the tool work. The whole process took maybe 20 minutes — of which Claude worked 19.5 and I only had to enter two or three small prompts.
The data question mattered to me: the board runs in the browser on my computer — so the data does not end up on the internet but sits locally with me. Normally it would be stored in the cache and be gone whenever I clean that up. So I told Claude: I want to be able to download the data into a folder of my own and load it back in later. Claude then set up an automatic backup as a file for me. The data is completely safe that way.
A little anecdote on the side: I dictate my instructions by voice — and “empty the cache” came out in dictation as “teach the cache”, as in teaching someone something. Opus 4.6 recognised from context that you do not lecture a cache, you empty it, ignored the mistake and simply carried on correctly.
Project 2: my local Canva alternative
My graphics program also starts from its own desktop icon. It does not look like Canva — but I can already do a lot with it: create canvases and set their size, add texts, change colours (even by hex code), adjust font and font size, insert shapes like rectangles — and the whole thing works with layers I can move around.
My prompt:
“Can you build me my own, locally hosted Canva — with all the functions Canva has?”
Claude first listed everything it could build in — that was very extensive. So I said: let us do a small MVP first, a very small solution, so I can see which direction it is going. A few minutes later it was done. I admit: it is still rudimentary. But the concept is clear — and in fine-tuning I can add more at any time: “I still want this, and that too.”
Project 3: my own CRM — the highlight
The most complex task I have given Claude Code so far was a CRM of my own. And I know what I am talking about: I have tested them all — HubSpot, currently I am on HighLevel, ActiveCampaign has a simple CRM built in, larger companies use Salesforce or SAP. The problem: these systems are maintenance-heavy and expensive — for solopreneurs in particular, that can become critical. So I was always on the lookout for a CRM that genuinely runs locally with me and causes no ongoing costs.
That is exactly what I have now built for myself. It runs on my computer (with test data, no real client data) and can:
- Contacts — manage them with all details, activities and emails per contact
- Company data — store it
- Deals — run them in the pipeline, including a status I can edit
- Meetings — plan them with participants, and afterwards I can upload the transcript from my Zoom meeting as the minutes
- Tasks — create them with description, priority, due date and an assigned contact
- Emails — draft them and assign them to the relevant contact — still manually for now, automation is the next step
My original prompt — again spoken freely:
“I want my own CRM on my computer. I want to store my client data, meeting minutes, emails, contact details — everything a good CRM like HubSpot contains.”
Claude then planned the architecture itself, and I could let the whole thing run on the side. After about two hours I gave feedback: meetings should be assignable to contacts, tasks too, and for the minutes I want to be able to upload files. Claude kept working — and at the end all that came from me was: “I want to start the whole thing via an icon on my desktop.”
For perspective: last year I myself started building my own CRM with other tools. I sat at it for weeks — and was nowhere near as far as I got now in a single day with Opus 4.6.
Why local? Data protection, €0 fixed costs, independence
For me, four things speak for building tools like this locally instead of paying subscriptions:
- Data protection: My data never leaves my computer. Client data, deals, minutes — everything stays with me.
- €0 fixed costs: No monthly subscriptions, no ongoing costs for tools I only partly use.
- Speed: The tools run directly on my computer, double-click from the desktop.
- Independence: I can adapt everything the way I want — and I do not depend on what a cloud provider plans for its product (or its prices). My CRM is moving to a Mac mini soon; a virtual server would also be possible.
Gift: my 10 killer prompts for Claude Opus 4.6
Want to start right away yourself? I have put together my prompt collection, with which you can build your own apps very quickly — free. Sign up, I will send it to you, and then you can work your magic however you like.
get the 10 killer prompts →Frequently asked questions
Which Claude Opus version should I use?
Claude Opus 4.8 — it is the current version. It costs the same as the older Opus versions but has a knowledge cutoff of January 2026 instead of May 2025. Anthropic now lists Opus 4.7, 4.6 and 4.5 as legacy; Opus 4.1 will be shut down on 5 August 2026. There is currently no argument for an older version.
Do I need programming skills to build my own software with Claude Opus 4.6?
No. I am not a techie — I talk to Claude Code the way words come naturally to me, and I even dictate my instructions by voice. What matters is not tech knowledge but knowing your business: what workflows do you have, where do you need support? Claude plans and builds the rest itself.
Do I need Claude’s expensive Max plan for this?
No, you can do this on the Pro version too. I worked with Claude for €18 a month for a year and a half and have only been on the Max plan for a few days — because my allowance was used up by all the projects. The finished apps themselves cost you €0 in fixed costs.
Where does the data of my self-built apps live?
Locally on your computer — it does not end up on the internet. So that nothing is lost when cleaning up the cache, have an automatic backup set up as a file in a folder of your own, like I did, which you can load back in at any time.
Conclusion: this is only the beginning
Three software solutions in one working day — programmed by Claude Code, instructed by me in plain language. With Claude Code you really can create all sorts of things. What matters is only that you know your business and know which workflows you have and where you need support — then you build exactly what you are missing.
If you want to learn how to do this again and again while staying up to date: in my free community — specifically for analogue natives, i.e. solopreneurs 45 and up — we exchange ideas about exactly these use cases. And if you want to bring Claude into your business from the ground up, have a look at the Claude Sprint.
