Promptshelf Stumble · 32 pages · 5 free aisles + Deep Cut · ?cat=&seen=&liked= URL
Random jump · 32 hand-picked pages · 5 free aisles + Deep Cut · updated 2026-04-25

Stumble the shelf.

One button. Thirty-two hand-picked AI-coding pages — games, tools, libraries, guides, starter kits. Pick the aisles you care about, press the big orange button, land somewhere you would not have thought to click. Inspired by StumbleUpon, which ran from 2001 to 2018 and at peak served 1.2 billion stumbles per month before the algorithm decayed and social feeds swallowed its idle time. At 32 pages, an algorithm is noise — curation is the product. Unlock the 6th aisle — Deep Cut — for 25 external high-signal links outside this shelf.

32 pages across 5 free aisles +25 external in Deep Cut ?cat=&seen=&liked= share URL one button · no account
Bay 01 · Pick your aisles

Which shelves are open?

Toggle aisles on or off to narrow what Stumble can pick from. Default is all five free aisles on. The 6th tile — Deep Cut — is an optional BTC-gated aisle of 25 hand-curated external links. A bitmap of your selection is encoded in the URL as ?cat= so the filter is shareable.

Bay 02 · Stumble

Press the button.

Picking uniformly from — unseen page(s) in your selected aisles.
Seen
0 / 32
Bay 03 · The whole shelf

Or skip the random and pick

Some people revisit — you remember the page, you just want to get back to it. The flat shelf below is a zero-friction lookup surface. Each tile shows the aisle, title, and a one-line tagline. Click the title to go, click the heart to add to your shortlist. Pages you have already stumbled are dimmed and struck through.

Bay 04 · Your shortlist

Hearted pages

Shortlist 0 items
Bay 05 · How it works

The ?cat=&seen=&liked= URL format

Three optional hex parameters. ?cat= is a 6-bit bitmap of aisle toggles (bit 0 Games, bit 1 Tools, bit 2 Libraries, bit 3 Guides, bit 4 Kits, bit 5 Deep Cut). ?seen= is a variable-length hex bitmap of pages already visited (one bit per page, ordered by sorted slug). ?liked= is the same shape as seen but for hearted pages. Omitted parameters default to empty sets and all free aisles on. Four worked examples:

?cat=1f
All free aisles on (default)
6-bit bitmap bits 0-4 set — all 5 free aisles on, Deep Cut off
?cat=01
Games aisle only
Only the 7 puzzles and quizzes eligible for the next jump
?cat=0c
Libraries + Guides only
Text-heavy reference reading — 6 libraries + 7 guides
?cat=1f&liked=800…
One hearted page shared
The liked-bitmap pre-populates your shortlist on page load
Bay 06 · Why Stumble?

A short history of random-page discovery

StumbleUpon (November 2001 — June 2018)

Founded by Garrett Camp and Geoff Smith in 2001 as a Firefox toolbar, StumbleUpon let a visitor pick interests and press one button to teleport to a hand- or algorithmically-surfaced web page matching those interests. Thumbs-up and thumbs-down votes trained the recommender. Peak metrics in April 2012: 25 million registered users, 1.2 billion stumbles per month. eBay bought it in May 2007 for $75 million; the founders bought it back in April 2009 for $29 million after the synergy thesis fell apart. It shut down June 30, 2018, migrating users to Mix.com (also now dormant).

It died from a mix of algorithm decay, a catastrophic 2011 redesign that deleted years of user-generated content and dropped traffic 25% overnight and 53% by late 2012, competition from Pinterest and Facebook's algorithmic feeds that captured idle-browsing time more effectively, and an ad-supported business model that conflicted with the serendipity promise — every sponsored placement eroded trust in the next random jump.

Successors worth knowing: Wiby.me indexes the classic / hand-authored small web and has a "Surprise me" button; Cloudhiker curates roughly 8,000 indie sites; Marginalia Search is a non-commercial search engine that explicitly up-ranks the obscure; The Forest is a human-reviewed random-link directory; Kagi Small Web bundles ~30,000 hand-authored sites into Kagi's paid search.

At 32 pages this shelf is nowhere near that scale. That is the point: with a corpus this small, every page is hand-vetted, an algorithm has no useful signal, and the only legitimate affordances are coarse aisles plus a seen-set. What you get back is the original StumbleUpon mechanic — one button, random jump, land somewhere new — without the algorithmic decay that killed the original.

Bay 07 · FAQ

Questions about Stumble

How does Stumble pick the next page?
Uniform random draw from the pages in your selected aisles, minus any page you have already seen this session. When every page in your selection has been seen, the visited set resets and you can stumble the shelf again. There is no interest algorithm, no collaborative filter, no cold-start cost — the corpus is 32 hand-picked pages, all equally eligible within whatever aisles you turn on.
Is this a StumbleUpon clone?
It's inspired by StumbleUpon, the web-discovery service that ran from November 2001 to June 2018 and at peak served 25 million registered users and 1.2 billion stumbles per month. StumbleUpon died from algorithm decay, a 2011 redesign that deleted user content and cratered traffic by 53 percent within a year, and the rise of algorithmic social feeds that captured the idle-browsing time it needed. The clone idea is honest: this is StumbleUpon restricted to one small shelf of AI-coding content where manual curation actually works.
What are the aisles and why five free ones?
Games (7 puzzles and quizzes), Tools (6 calculators and configurators), Libraries (6 reference collections), Guides (7 how-tos), and Kits and Comparisons (6 starter kits and vs-pages). Five is the coarsest split that keeps each aisle roughly balanced — fewer than five and the aisles blur; more than five and the selection UX gets noisy. There is also a 6th aisle called Deep Cut, which contains 25 hand-curated external links to high-signal resources outside this shelf. Deep Cut is included in the one-time 5,000-sat confirmed payment that unlocks all seven current priced features site-wide.
What is Deep Cut?
Deep Cut is a 6th optional aisle containing 25 hand-curated external links — benchmarks, visualizers, reference guides, podcasts, pricing tables, and foundational AI coding essays not on this shelf. It is included in the one-time 5,000-sat confirmed payment that unlocks all seven current priced features site-wide, verified by the shared client-side /gate.js verifier via mempool.space + blockstream.info. Deep Cut destinations open in a new tab. The 5 free aisles are completely unaffected — Deep Cut is strictly additional. Once verified, the aisle is stored in localStorage and persists across visits on the same browser; the same TXID can be re-pasted on any priced page.
What does the share URL format mean?
Three optional hex parameters. ?cat= is a 6-bit bitmap of which aisles are on — 5 bits for the free aisles (Games, Tools, Libraries, Guides, Kits) + bit 5 for Deep Cut — so ?cat=1f means all 5 free aisles on, ?cat=3f means all 6 including Deep Cut, ?cat=03 means only Games and Tools. ?seen= is a variable-length hex bitmap of pages already stumbled, one bit per page in the sorted corpus index. ?liked= is the same shape as seen but for pages you have hearted. Omitted parameters default to empty sets and every aisle on.
Why does the destination open in the same tab?
Mobile browsers treat new-tab clicks as popups and block them, and StumbleUpon itself always redirected in place in the browser toolbar. The pages themselves each carry a small floating pill that says Stumble again when you arrive via a Stumble link — the pill only appears when the URL contains ?_ps=1, so it does not clutter the page on normal visits (the reserved underscore-prefixed key avoids colliding with any product's own share-state params). Press the pill to return to the remote and jump somewhere new.
Where does the shortlist save?
Locally in your browser via localStorage under the key promptshelf-stumble-v1, and in the shareable URL under ?liked=. Both are mirrored on every heart or unheart. There is no account, no server, no analytics pipeline. Copy the URL to share your shelf to a friend; clear browser storage to reset. No confirmation dialog, no undo — this is a hand-tool, not a product.
Why no thumbs-down button?
StumbleUpon had both thumbs-up and thumbs-down and the down votes drove the personalization algorithm. At a corpus size of 32, personalization is noise — if you down-vote two pages the algorithm has nothing left to learn from. The seen-set already filters out pages you have walked past; aisle toggles let you carve the space further; that is the total legitimate affordance at this scale. Adding thumbs-down would be cargo-cult StumbleUpon without the user count to power it.
What if the shelf grows past 40 pages?
The bitmap scheme handles it. ?seen= and ?liked= are variable-length hex — 32 pages is 8 hex digits, 40 pages is 10, 64 pages would be 16. Pages are ordered by alphabetical slug so adding a new page at position N just inserts a bit without re-ordering anyone else's share link. The aisle list is fixed at five; new pages join an existing aisle rather than spawning a new one.