Quelin Zammit
I build the second source.
Most of these repositories decide something by producing an independent second artefact and comparing it against the first, rather than by asserting. A contract against the page as it is served. A ledger against a settlement report. The same agent with the policy on and off. It is the same move each time and it is deliberate, so it is better said here than discovered on the fourth repository and mistaken for a formula.
Underneath all of it is one idea: designing for the failure that does not announce itself. Systems that fail loudly are a solved problem. The expensive ones keep returning success.
What each one compares against what
| QUACKZ | the audit's own recomputation against the returns the backtest claims |
|---|---|
| QUOTEZ | none, and this is the exception |
| QUELLZ | the bare agent against the same agent under containment |
| QUIDZ | the delivery stream against the ledger against the settlement report |
| QUESTZ | the recorded contract against the page as it is served today |
| QUIZZ | the publisher's own first, second and third release figures against the levels this corpus records |
| QUARANTINEZ | the decision recomputed from the stored row against the decision the crashed process was going to write |
| QUENCHZ | a TypeScript client on the official SDK, driving the audience and budget proofs from outside Python |
| QUILTZ | the same configuration planned by a second, independently licensed binary |
| QUAYZ | the same decision implemented twice, as a Python taxonomy joined to the cluster matrix and as a Go classifier tested against a real kube-apiserver under envtest |
| QUARRYZ | the same as-of definition written three ways and run against three engines, ClickHouse, DuckDB and PostgreSQL, compared on every period rather than on the headline one |
| QUASHZ | a swept positive control and a 200 draw permutation null on the same yardstick, so a result and a null result are both bounded by what the procedure could have found |
| QUALMZ | the same schema and the same rules run against SQLite in the offline suite and against a real PostgreSQL in their own job, where the role-scoped grant is watched refusing |
| QUEUEZ | the same normalisation written twice, in Python and in a dependency-free Rust binary, compared line by line over every event, with neither one treated as the reference |
13 of 14 carry the move. QUOTEZ does not, and saying so is the point: a thesis that survives only by leaving out the case that breaks it is not a thesis. That repository argues something narrower instead, that a capability which does not exist cannot be misused, and it has no second artefact because it has no write path at all.
Grouped by what they argue
Selection and measurement: a number is only as good as what it counts and what it was selected from
- QUACKZ deflating a backtest that only looks good because it was picked out of two hundred
- QUIZZ answering what a statistic said at the time, and refusing when it cannot
- QUARRYZ keeping every version a statistical office published, and failing the build when it quietly issues another
- QUASHZ refusing a row whose outcome had not been decided yet when the decision would have been made
- QUALMZ a fixed number of looks at the holdout, where re-running the same configuration does not buy another
A capability that does not exist cannot be misused
A silent change in an external surface must become a loud stop
- QUESTZ stopping a scraper before it writes a CSV from a page that changed shape
- QUARANTINEZ treating an outcome the venue never confirmed as terminal rather than as a retry
A test is only worth what its boundary admits: an emulator result with no stated limit is a claim about production nobody made
- QUILTZ proving infrastructure code wrong without a cloud account, and saying what that cannot show
Admission: who is calling, what may they reach, whose budget do they spend, and how much of the answer actually arrived
- QUENCHZ deciding in the open what a tool server gets free while it is still somebody's subprocess
Designing for the failure that does not announce itself
- QUEUEZ ordering a feed by its sequence, because on a real recorded session the clock goes backwards
Noticing a bad deploy is not the hard part. Reaching for an instrument that cannot tell you which failure it is, and believing what it says, is the expensive one
- QUAYZ telling a crash loop from an OOMKill, and naming the failure that no single field finds
Repetition and disorder in delivery must not change the arithmetic
- QUIDZ refusing the outbound payment that would have gone out twice
The technology view
| Python 3.11 to 3.14 | every repository, every version tested in CI |
|---|---|
| pytest | the suites, offline and deterministic in all five |
| ruff and mypy | lint, format and types, all three gating every push |
| GitHub Actions | the matrix, and the Pages deployment behind each card |
| uv | resolution and the lockfile, one command from clone to output |
| mcp | QUOTEZ the Model Context Protocol server an agent connects to QUIZZ the Model Context Protocol server an agent connects to QUENCHZ the Model Context Protocol server an agent connects to |
| anthropic optional | QUELLZ a real model behind the same interface the fixture implements QUIZZ a real model behind the same interface the fixture implements |
| pydantic | QUIDZ request models on that boundary QUENCHZ request models on that boundary |
| uvicorn | QUIDZ the ASGI server, needed only to bind a socket QUENCHZ the ASGI server, needed only to bind a socket |
| fastapi optional | QUIDZ the one module allowed to import a web framework |
| greenlet optional | QUESTZ Playwright's sync API |
| httpx2 | QUENCHZ the one HTTP client in the tree, named by the MCP SDK itself so there is not a second |
| langgraph | QUIZZ the agent loop, as a state machine whose one creative step is choosing a tool call |
| MetaTrader5 optional | QUOTEZ the live market data terminal, behind an optional extra |
| numpy | QUACKZ the arithmetic behind every backtest verdict |
| pandas | QUACKZ return series and resampling |
| playwright optional | QUESTZ a real browser for the end to end leg |
| pyjwt | QUENCHZ signature and audience verification, where the audience is the check that matters |
| starlette | QUENCHZ the ASGI application the MCP SDK builds, and the reason no web framework is needed |
Read out of each repository's own pyproject.toml when this page was
built, not typed here. A dependency with no recorded role stops the build rather than being
quietly dropped, because a list that omits what it does not recognise is worse than no list.
What is not here
This shows what is published. Every card on it is a repository you can clone, run offline in under a minute, and check against its own claims; there is no link on this page that goes nowhere, and no entry for work that is planned rather than shipped. More is being built, and it appears here when it exists and not before.