Wall shelf for pantry: What is stable enough?

I used to drill strips on every side wall (at the same height on the left and right), and then put shelves on them. But it just feels that way with drywall and such. That's why I would use frames.

Without dimensions and loads, little help can be given.

The dimensions are 1.8m x 1m in L-shape. I want to have 6 shelves. The one/two-row rails from the hardware store are really flimsy. I was able to bend them quite easily with little pressure. I have now found Tegometall. If I can get them nearby, I would take them. They are 23.5mm x 30mm and 2m long. They seem to be very stable.

I simply built 4x5cmx250cm pieces of wood like a ladder and laid boards on top. Costs under 100 euros. Even holds water crates, etc.

If you don't trust your wall, place it on the floor. Custom-made to size, either from wood, as writes, or you take something like the Vario angle profile with holes and build your frame from it, which you can then cover with wooden boards, OSB, or something else.

... I have now found Tegometall. If I can get it nearby, I would take it. They are 23.5mm x 30mm and 2m long. They seem very sturdy.

Tegometall is a real standard in the commercial sector (food). They are virtually indestructible, modular, and price-stable. Often available used on eBay (classifieds). I have assembled and disassembled tons of them. But you need some room to maneuver when hanging the shelves, is that given? If the space is very limited, assembly could be difficult. Otherwise, I can recommend them. I myself have nearly 20m of much nicer META heavy-duty plug-in shelves standing in the cellar. Stable, nice (if you like industrial design), easy to keep clean. Quickly snapped together (or reassembled). In my future utility room (in the solid wood house), of course something natural made of wooden boards will go in :)