01
One landing, one ad campaign
New ideas get a single page and a Google Ads campaign first. Real clicks, real cost-per-lead data — before a line of product code. The older products on this board predate the method.
rathgeber.dev — build in public
Stéphane Rathgeber
I build small SaaS products and kill them fast when the market says no.
This page is the whole portfolio: live products, experiments running on real ad budgets, and honest kills — with the strategy behind each call.
12
products
4
in validation
2
live today
€0
current MRR — all of them
01 — The board
Every product, its real status.
Four stages, in the order a product goes through them. Unfold a card for the strategy — or the lesson.
-
Landing — 4 products
A landing page and ads are live. The product does not exist yet.
-
ReminderProof
Appointment reminders that reach the inbox, sent from your own domainStrategy
No ads on this one: the qualification is free and public. A DNS scan tells any dental practice whether its domain enforces DMARC — 87% of the 2,482 practices we measured do not, which means their reminders can be filtered before a patient ever sees them. That scan is both the targeting and the opening line of the cold email, and the prospect can verify it themselves in seconds. Priced at $179/month behind a payment wall, so the test measures intent to pay, not curiosity.
Live data · as of 2026-08-09
- Cold emails sent
- 60
- Bounced
- 3
- Leads
- 0
- Price tested
- $179/mo
Read so far — Day one, so nothing is decided. What the first 60 emails did settle is the plumbing. The opening batch bounced at 10% — three addresses that had a valid MX but no live mailbox behind it, because the list had only ever been checked at the domain level, never at the mailbox. An SMTP probe that stops short of sending re-qualified the whole list: 525 of 684 addresses confirmed, catch-all servers excluded because their acceptance proves nothing. The next 30 bounced at 0%. On 30 sends that does not prove a true zero — the confidence interval still reaches 11% — but the fault we identified did not recur, and it cost nothing: the $90 paid-validation service was never bought.
-
CertifiedWeekly
Certified payroll filed weekly for public-works contractors — unlimited jobs, one flat priceStrategy
No fake door on this one: the method is to recruit five design partners and build it with them. They send a real payroll week, we return a file they can actually upload, they say where it is wrong — first year free, founding price after that. The targeting comes from a public record rather than a scrape: Washington publishes both its public-works contractors and their upcoming jobs, so the 193 companies contacted all have a job starting before 31 December and apprentices on it — apprentices being the part of the filing that takes six lookups across three separate tools.
Live data · as of 2026-08-15
- Targeted
- 193
- Emails sent
- 0
- Design partners
- 0 / 5
- Offer
- 1st year free
Read so far — The whole pitch rested on one assumption: that filing certified payroll could not be automated by a file import, which would make a paid service pointless. The question went to Washington L&I on 8 August and, a week later, is still unanswered — but the answer was public the whole time. L&I has accepted XML uploads since 2020, schema published. That should have killed the idea. It did the opposite, because of how the state tells you to produce the file: "Program to Create/Edit a XML File: Notepad (PC), Textedit (Mac)." Case-sensitive trade codes, classifications that shift with the award date, six apprentice fields spread across three lookup tools. The vendors who automate it charge $175/month plus $995 to set up, or $145/month per job; the ones with a modern self-serve model — including one launched five months ago on this exact positioning — do not cover Washington at all. So the product moved from "we file for you" to "you never touch XML", and the method moved with it: not a fake door, but five contractors who get the first year free for building it with us. The lesson worth keeping is the week spent waiting on a government reply that was already published on its own website.
-
BeforeTheChair
Insurance benefits verified before the patient sits down, at a flat monthly priceStrategy
Same dental practices as ReminderProof, different pain: verifying insurance benefits eats front-desk hours and gets billed per verification by everyone else. Flat $199/month against an incumbent at $450/month for 50 verifications.
Live data · as of 2026-08-09
- Verified prospects
- 465
- Cold emails sent
- 0
- Leads
- 0
- Price tested
- $199/mo
Read so far — The least advanced of the three, and it has a scheduling problem rather than a product one. It shares its prospect list with ReminderProof — and a practice already contacted about email deliverability is no longer a clean test for insurance verification. 60 of the 525 verified addresses are spent, 465 remain. No cold email has been written for this angle yet, so nothing has been sent. It waits until the first test has said something either way.
-
MonLogicielPraticien
All-in-one practice software for wellness practitioners (agenda, patients, billing)Strategy
Different validation channel: free practice audits run through a Facebook community of practitioners, instead of paid ads. GDPR-first, hosted in France.
-
-
Beta — 5 products
The product exists and people can use it. Early, rough, still moving.
-
refply
Flat-fee affiliate platform for SaaSStrategy
The only one of the three fake doors that stopped being a door. An application now runs on app.refply.com — Stripe Connect and Lemon Squeezy connected, attribution read off payment-provider webhooks rather than a third-party pixel, so a conversion survives Safari and ad blockers. The private beta is invitation-only and asks for a card that it is structurally unable to charge: the billing client allowlists three Stripe endpoints and throws before any other HTTP call. The point is to find out whether someone will hand over a card at all, which no landing page can answer.
Live data · as of 2026-08-09
- Ad spend
- 593 €
- Clicks
- 196
- Leads
- 16
- Cost / lead
- 37 €
Read so far — Sixteen signups at €37 each reads like the best result of the three — and most of that number is an artefact. The campaign ran on Google's default geo setting, PRESENCE_OR_INTEREST, which serves not only people inside the targeted countries but anyone showing an interest in them. On a campaign named "Search US-UK-CA", nine of the sixteen signups came from outside it: Bangladesh, Pakistan, India, the Philippines, Zimbabwe, Croatia. redemo, correctly set to PRESENCE, was hit by nothing of the kind — the comparison isolates the cause with no ambiguity. Fixed on 2 August, and the leads arriving since are visibly better: the two most recent are named people at real company domains. Counted on target rather than raw, the cost per signup is nearer €85 than €37, and the strict ICP — Stripe, Paddle or Lemon Squeezy *and* $1–50K MRR — is still met by one or two of them. €593 of the €1,000 cap is spent. That is where the ads stop being the interesting part: this is the one test that graduated out of the fake door, and the question moved with it. Not "will someone leave an email" — sixteen did, and it taught us mostly about Google's geo defaults — but "will one of the two servable leads put a card on file". No one has yet. Until someone does, a beta badge means an application exists, not that anyone wanted it.
-
redemo
Product demo videos re-rendered from your live product, not re-shotStrategy
Total dogfooding: the demo video on redemo's own landing page is produced by the very pipeline the product sells. Delivery is still concierge — each video is rendered by hand for the first accounts — so automatic regeneration is what the product is being built towards, not what it does today.
Live data · as of 2026-08-09
- Ad spend
- 954 €
- Clicks
- 343
- Leads
- 7
- Cost / lead
- 136 €
Read so far — €954 of the €1,000 cap is gone, and the cap is what will end this test. Ten signups arrived in all; three were fake beyond argument — a disposable mailbox, a domain with no DNS at all, an address ending in .ckm — and two more came from datacenter IPs with no plausible explanation. That leaves seven, five of them beyond doubt, at €136 each against a GO line at €80. Traffic was never the problem: 343 clicks, a 16% click-through rate, and geo targeting correctly set to PRESENCE so the audience really was American. Conversion is the problem, and it has stopped: the last credible signup was 30 July, while €372 was spent in the ten days after it. Every additional click now pushes the cost per signup further from the threshold.
-
Gaina
AI phone receptionist that answers, qualifies and books appointmentsStrategy
€49/month, plugged into the existing phone line without changing the number. Sold one vertical at a time rather than broadly: cold outreach to driving schools produced the first real signup, and during the beta the product is given away in exchange for feedback — early users are worth more as evidence than as revenue.
Live data · as of 2026-08-09
- Ad spend
- €0
- Vertical pages
- 6
- Signup forms
- 0
- Price
- €49/mo
Read so far — The product is live, the app answers, six vertical landing pages are published — and not one of them carries a form. Zero <form> tags, zero inputs, across every page checked. Whatever the traffic does, the site currently has no way to capture it, which makes the acquisition question unanswerable rather than unanswered. That is the first thing to fix, before any budget goes anywhere near it. Named vertical so far: driving schools, reached by cold email, one real signup.
-
IdeaScorer
Scores your SaaS idea 0–100 from real signals (Reddit, HN, GitHub, Trends)Strategy
Eat-your-own-dogfood tool: the same market-signal scoring used to pick which SaaS ideas on this page get a validation budget. Two agents run it unattended every day, one sourcing pains, one ranking them the next morning.
-
ludotracker
Board-game tracker growing into a players' networkStrategy
Started as a board-game collection and plays tracker. The real bet: grow it into a social network of players, then monetise through affiliate links to the games they track, want, and recommend to each other.
-
-
Prod — 2 products
Shipped, in production, used for real.
-
zerotrusttransfer
Digital vault & zero-knowledge file transfer, hosted in FranceStrategy
Two linked modules: ZeroTrust ID for encrypted identity documents, and ZeroTrust Share for two-key encrypted vaults. Both are shipped and online; paid acquisition was stopped on 30 July 2026 and the product now waits for a channel that is not Google Ads.
Live data · as of 2026-08-09
- Ad spend
- 549 €
- Clicks
- 3774
- Leads
- 0
- Cost / lead
- —
Read so far — 3,774 clicks, not one signup, across three campaigns and €549. A conversion tag that fired on the wrong page hid the result for a while, but fixing it changed nothing: the corrected tracking and the traffic never overlapped, so the zero was never a measured conversion rate. The real reason came from keyword research, which does not depend on tracking at all. Nobody searches for secure file transfer: the security angle draws about 210 searches a month in France, against 12,400 for the plain free-transfer query. The product is not what failed — the demand it was sold against does not exist at that price of attention. Ads have been off since 30 July, and the account confirms it: €0 and zero impressions since.
-
stareply
AI-written replies to Google reviewsStrategy
Aimed at the French market. Try it without an account for three replies, then €9.99/month for one Google Business Profile with unlimited replies. A US version was considered and dropped: 230 searches a month, a price floor set by competitors at $5–19, and Google folding the feature into its own console.
Live data · as of 2026-08-09
- Price in the app
- €9.99/mo
- On the brochure site
- €29/mo
- On stareply.io
- €79/mo
- Free tier
- 3/mo
Read so far — Shipped and used, with a problem worth stating plainly: three different prices are live under one brand — €9.99 in the app, €29 on the brochure site, €79 on a second landing page. Only the first is what a customer is actually charged. The application was corrected and deployed on 7 August; the brochure site, which is the front door of the brand, still advertises a free tier of 10 replies a month and a €29 plan that nothing bills. This entry used to repeat that claim. It was wrong, and it is the reason the fix is now the next thing on the list.
-
-
Killed — 1 product
Stopped on its own thresholds. The lesson stays public.
-
sourcemylead
Lead-source attribution that writes into your CRMStrategy
Fake-door test: one landing page plus Google Ads, and a GO/KILL decision against thresholds written down before launch. Hard budget cap of €1,000, ads included.
Live data · as of 2026-08-09
- Ad spend
- 169 €
- Clicks
- 13
- Leads
- 1
- Cost / lead
- 169 €
Read so far — Stopped at €169 of a €1,000 budget, campaign paused since 30 July and silent since. The €13 cost-per-click was not a settings problem: once the bids were corrected and the ad-tech noise filtered out, the campaign stopped serving altogether — that price was the market, not a mistake. Keyword research then showed the wall. Every cluster holds two of the three qualities this needed, never the third. "Call tracking" has the volume — 22,000 searches a month on the CallRail brand alone — and real buyers, but demands phone tracking this product does not do. "UTM tracking" has the volume and matches the product exactly, and zero advertisers, because Google hands that tool out for free. "Lead source tracking" has the buyers and the product fit, and twenty searches a month. The landing converted at roughly 8%: the channel was wrong, not the page.
-
02 — Method
How an idea lives or dies here
02
An honest fake door
The signup form is a fake door, and it says so on the page: “private beta, onboarding within 48 hours.” Nobody gets access to a product that does not exist yet.
03
Contractual GO / KILL thresholds
Thresholds are written down before launch and read after 6–8 weeks. No reinterpretation, no extension because it “almost” worked.
04
€1,000 per idea, communicating vessels
Each test is capped at €1,000, ads included. Whatever a killed idea doesn't burn flows to the best-performing one still on the board.