Items you collect can be constructed from other items or by collecting resources in game. Typically you'll use various recipes combined with the ingredients you find to make new items.
Pretty sure everything is indie on itch.io but just in case you want something extra indie.
Explore games for Web with subtitles tagged Crafting and Indie on itch.io · Sell your games for Web with subtitles on itch.io to have them show up here.
Subscribe for game recommendations, clips, and more