Hmm im not aware. I was thinking in using this from nostr:npub1uac67zc9er54ln0kl6e4qp2y6ta3enfcg7ywnayshvlw9r5w6ehsqq99rx https://github.com/sandwichfarm/encoded-entities#nfeed---filters--relays . So you could encode timelines in nfeed strings. Also i was thinking in adding "presets" to create timelines, like "my friends" or "from follow pack", etc. Ideally all of this is shareable and portable so you can encode your feeds in strings and load them anywhere