Build1 publisher3 min readPublished
The Vinted scraper passed 73 tests and cleared a DataDome target on the cheapest proxy tier. It sat unmerged for 19 days because nothing in the build lane ever read main's tree.
The Engineer · Build desk
Follow any of these and your For You feed starts watching them — no settings page required.
Compiled by The EngineerSomething wrong?How this is made
The harvest is the step with no durable state on either side of it. An agent works in its own git worktree, takes a target from spec to local-green, commits to its branch, and reports back; the orchestrator is then supposed to merge that branch into main [5]. The commit leaves a record. The merge leaves a record. The report between them is a message in flight, so when a watchdog kills the agent or the orchestrator simply moves on, nothing in the lane looks at that branch again [6]. The scoreboard had already counted the build at local-green [7].
The reconciliation query is obvious once you accept that: for each worktree-agent branch, diff it against main, keep the paths under actors/, and flag any slug with no directory in main [9]. The hit was a whole scraper, models and client and parser plus four test modules on real fixtures, committed 2026-07-29 [10]. Nineteen days puts the discovery around 17 August [22].
The 19-day-old local-green claim was not taken on faith. Fresh virtualenv, full test run, and the input-schema prefill validator confirmed the Actor's default input still deserializes into its input model [11]. Only then did it go to the cloud, where run f5QniR52Jf1UNC4oO succeeded with 3+ rows [12].
The bill is the part worth copying. Compute units account for $0.000955 of the $0.001050 total, about 91 percent, and 0.00477417 units at that price implies $0.20 per compute unit [13][19][20]. The record's key evidence is a missing line: logs do not record which network a run used, so the missing residential transfer entry is the only proof that a DataDome-protected target cleared on cheap proxy [14][13].
That is one run producing 3+ rows [12]. It shows the block can be beaten on that network at that moment; it is a single data point, not a success rate. For the figure to transfer to a target of your own, the same tier would have to hold under sustained volume, and nothing here measures block rate under load. What a tenth of a cent buys is the standing to delete the word infeasible from a backlog line: proof that the target can be cleared, not a throughput estimate [4].
The direction of the surprise has now repeated. A business-directory target was shelved as Camoufox-class and infeasible after a residential-only probe, then later cleared cleanly on plain datacenter proxy while residential and a full stealth browser both failed [15]. The author's reading is that tier strength does not predict success, because networks carry different reputations at different targets [16]. Hence the rule that a NO-GO is valid only if it names every tier probed [17]. The rule needs its own verifier: in the batch of five Actors forced onto residential, two billed zero residential bytes, 40 percent of the batch, and both would otherwise have been filed as residential probed and still blocked, which is a false NO-GO manufactured by the rule written to prevent them [18][21].
What this does not settle is the other half of the original note. The do-not-build entry gave two reasons, DataDome and a saturated incumbent at 108k runs with a five-star rating [1]. The cloud run answers the first and leaves the second where it stood, and the writeup puts no figure on what the untested NO-GO cost in engineering time or forgone revenue [23]. The reconciliation step is cheap, and it has to run on a schedule rather than at harvest time, because harvest is the step that fails.
Ranked by verification strength, evidence, and original report placement.
The team keeps a written do-not-build list. Vinted had been on it for months with a one-line reason: DataDome, plus a saturated incumbent at 108k runs and a 5-star rating.
When finally run against the live site, the scraper passed on the cheapest proxy tier available, with no residential network and no browser automation, for $0.00105 in platform cost.
The 'DataDome, infeasible' note in the backlog had never been tested against the actual site; no cloud run had ever touched this Actor.
The first real cloud run passed: vinted-sold-listings run f5QniR52Jf1UNC4oO SUCCEEDED with 3+ rows.
The billing record for the run: ACTOR_COMPUTE_UNITS 0.00477417 at $0.000955; KEY_VALUE_STORE_WRITES 1 at $0.000050; DATA_TRANSFER_INTERNAL_GBYTES 0.00043767 at $0.000022; DATASET_WRITES 3 at $0.000015; DATA_TRANSFER_EXTERNAL_GBYTES 0.00001517 at $0.000003; total $0.001050. There was no residential transfer line, so the run did not use the residential tier.
A Vinted scraper the team had already finished sat unnoticed on a git branch for 19 days because the build lane counted 'the agent said it was green' as done instead of 'the code is in main'.
Evidence-backed comparisons of source perspectives and observed adoption signals. Read the methodology
Which Builder, Operator, and Investor concerns the observed source mix emphasized—not a truth score.
Evidence, demonstrated adoption, hype gap, incentives, and confidence are assessed independently, each on its own current evidence. How these are measured.
Specific artifacts, one witness
Every number traces to one team describing its own systems: run f5QniR52Jf1UNC4oO, five billing lines totalling $0.001050, 73 passing tests, 97 leftover branches. None of it is openable from outside. What lifts it above anecdote is that the author states the limit of his own instrument, noting that datacenter proxy has no billing line so a run with no proxy transfer is either datacenter or direct, and that only residential is definitively excluded. The residential-batch audit carrying the second half of the argument arrives with no run IDs at all, which is exactly the evidence the Vinted section supplies.
One Actor, one run, one day
The demonstrated use is a single successful cloud run returning three rows against a target the same team had refused to build for months. No customer, no second run on a later date, no sign of the marketplace's defenses reacting. The durable part is internal: a NO-GO now has to name the tiers probed, and the QA tooling will not record a verdict when the requested tier did not apply, which is adoption of a process rather than of a product.
Hedged numbers, generalised moral
The cost claim is stated more cautiously than most vendor posts manage: one tier, one day, with the datacenter-versus-direct ambiguity spelled out and the promise that Vinted is easy to scrape explicitly withheld. The loose seam is the generalisation. Two cases, one of them an unnamed business directory with no artifacts, become a claim about how proxy networks earn reputations at different targets. The two-line sweep also travels less easily than the headline implies, since it depends on branches named worktree-agent-* and one directory per Actor slug.
The demo is also the storefront
The Actor whose first run this is sells at $0.0025 per row, and the closing lines point at OfferUp, Poshmark, Craigslist and eBay as next in the series. A vendor showing a DataDome-protected marketplace falling to the cheapest proxy tier has an obvious reason to publish the cheap number. The same vendor also printed the paragraph conceding that billing cannot distinguish datacenter from a direct connection, and led with a failure of his own build process, both of which work against the sales pitch.
Plausible, unverifiable
The engineering detail is too specific and too self-critical to read as invention, and the arithmetic checks out against the published lines. Set against that: a single self-published account of a private pipeline and a private billing record, with the strongest general lesson supported by the weakest documented case. Anyone acting on this should copy the two checks and treat the Vinted result as one data point.
build
Anti-bot systems now score the session, which means your proxy pool is not a mitigation1 publisher
build
Agent-written PRs move the bottleneck to whoever still has to read them1 publisher
build
A trailing newline in Vault forced 112,228 escalations onto the 72x-cost proxy tier1 publisher
build
Four Actors topped a cost table on RAM they never used1 publisher
Publishers with included, body-backed reporting in this cluster.
1 article · September 6, 2026