May 2026 update

In May we shipped the editor features users had been asking for: undo, batch generation, and faster loading. We turned on company billing, so studios can pay as a team and move from pilot to paying account. We rebuilt Design Mode around a chat agent. We started pilots with more architecture and interior design firms. And the firms that spent their pilots comparing us with our competitors are choosing us.

May in numbers

• 10 phases shipped. Planned, executed, tested, deployed.
• 119 new tests. 96 frontend, 18 backend, 5 end-to-end.
• Worst-case canvas freeze cut from 16.7 seconds to 0.27. Measured on a 4K upscale.
• 1,300 lines of legacy code removed. The old Fabric.js drawing engine, dropped.

Shipped

Undo and redo. Ctrl+Z and Cmd+Z now work across the canvas: layer moves and deletes, vector placement, handle drags, rotate, scale, and toolbar edits. We rebuilt the edit path so every change records its own inverse and adds one step to the history. Drag five layers at once, undo, and all five go back together. The same work let us remove the old Fabric.js drawing engine. It was our most-requested feature.

Company billing. Paid organizations now share one credit pool with proper multi-seat invoicing. Each seat gets its own tier, and we handle the full Stripe lifecycle: invoices, subscriptions, tax, and a dunning flow for failed payments. German VAT is built in, including Kleinunternehmer status and PAngV price disclosure. We also simplified the pricing and added a magic-link cancellation page, so leaving never needs a support ticket.

Batch generation. Pick a count, press Generate, and we run the requests together, drop the results into a stack, and expand it into a grid once there are two or more. New images now land in a placement grid next to their source instead of on top of the original, which keeps the workflow moving. The batch is saved as it runs, so reloading partway through never loses a result.

Performance and reliability. We rebuilt canvas image loading around one queue with a concurrency cap: thumbnails load first, full resolution fills in behind. We moved image encoding into a worker off the main thread, which cut the worst-case freeze on a 4K upscale from 16.7 seconds to 0.27. We also built a defense against a database crash that hit when the browser’s storage filled mid-session: it recovers instead of failing, and refuses to reload when that would cost unsaved work. 62 tests cover it.

Design Mode chat. Design Mode is our flow for rendering CAD drawings and photos. In April it could classify your image and walk you through a fixed menu. In May we gave it a chat agent. It recognizes five kinds of input, tells twelve kinds of architectural drawing apart (elevations, sections, axonometrics, and more), and renders each in its own style while keeping technical drawings on their true view. It keeps a separate chat thread for each image and remembers where you left off. That is about sixty input situations, up from roughly nine.

Model reliability. We added no new models this month. We made the dozen image and video models we already run faster and more reliable, and moved our whole Gemini stack onto Google’s stable endpoints before the preview ones retire on July 17, with no interruption. We also fixed an empty-response bug on Gemini, fixed GPT Image 2 output that was finishing but never reaching the canvas, and removed a “Veo Fast” label that pointed at the standard model.

On the road

RenderTube workshop and Testat I at TUM. We ran another workshop in TUM’s RenderTube course, where architecture students use Interstitial to learn visualization, and we came back as guest critics for their Testat I reviews. Teaching architecture students is also some of the fastest feedback we get.

Google hackathon. Google invited us to a hackathon for its business partners and a few startups, with their engineers helping us work through our own problems. We were one of the youngest companies there. We used the time to push on our agent system, which we want to grow from a design helper into an assistant that can understand and operate the whole app. We also found inefficiencies in our cloud and storage setup that we plan to fix soon.

Learned

B2B work is unglamorous and necessary. Bilingual GDPR documents, a German imprint, self-service cancellation, two-click confirmations on destructive admin actions. None of it is exciting, and all of it is what a firm checks before it signs. May had a lot of it.

Some users find us through Claude. A few new users told us they found us by asking Claude for a tool to visualize architecture, and it recommended ours. We did not pay for that and cannot, but it is becoming a real way people find the product.

Next

• A real agent. Growing the design helper into an assistant that can understand and operate the whole app. This is what we worked on at the Google hackathon.
• Plugins. Our Revit plugin gets Revit 2026 support, on top of the 2025 version it runs in today. We are starting work on Archicad and Rhino, with more to follow.
• Pipeline canvas. Connecting generations into reusable pipelines, right on the canvas.
• Bigger sharing. Read, write, or copy access, shared by a link or inside your own studio.
• Colormaps and alpha maps. Colormaps you can upload and download for automatic segmentation, and alpha maps for masking.
• Regional editing. Coming back, with pixel-perfect control over what gets edited and what does not.
• Co-editing on one canvas for up to twelve. We have already built and shipped the backbone that lets multiple people work on the same canvas at once. Now we are turning it into full co-editing, for up to twelve people at the same time.
• Leaner cloud and storage. Acting on the inefficiencies the Google hackathon surfaced.

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Interstitial is an AI-driven architectural visualization platform built in Munich. We send build updates monthly. Contact