Security
Defensible by construction.
Signum exists to be handed to somebody whose job is to doubt it. What follows is the posture as built, including the parts that are limits rather than features.
Tamper-evident records
Transcripts and extractions are content-hashed over a canonical form and chained revision to revision. The audit log is hash-chained per tenant and can be anchored with a signed head held outside the database, so even an insider rewrite is detectable.
Encrypted at rest, bound to context
Sealed payloads use authenticated encryption with the ticket, document class and revision as additional authenticated data. A record lifted out of context will not decrypt. The adapter proves it can decrypt what it seals at start-up, or the application refuses to start.
Redaction at read time, per consumer
The transcript keeps what was said; each consumer receives what it is entitled to. Credentials, wallet addresses, identity-verification fields, account numbers, contact details, tenant names and market-sensitive phrases are detected and suppressed. The redactor fails closed: an internal error returns fully masked output, never the original text.
Least privilege and approval
Ranked roles, SSO through OIDC or SAML, SCIM provisioning, and login throttling checked before any password hash. A non-administrator’s mutating action becomes a request awaiting approval rather than a refusal.
Signum Memoria
Reading your knowledge is a bigger blast radius than reading one channel.
A system that indexes the places your organisation keeps its knowledge is a system that can leak all of it at once. Memoria’s controls are built on that assumption, and the ones below are invariants — there is no parameter that turns any of them off, and the configuration registry does not contain a key that could.
- The classification ceiling is enforced inside the query. Not as a filter applied to results afterwards. A post-filter is one bug away from returning what it was meant to hide; a condition inside the SQL cannot return the row in the first place.
- The ingestion gate has no bypass. No code path skips it, including test paths. Content reaches the corpus through review and a named human approval, or it does not reach it.
- The audit log is append-only at the database. The application connects as a role that has no UPDATE or DELETE on it, so this is a privilege, not a convention the code is trusted to observe.
- Allow-list only, with no “sync everything” mode. You name each source. The absence of that mode is deliberate and the code does not contain one, because the cheapest place to stop an unreviewed disclosure is at the door.
- Upstream restrictions are honoured by exclusion at ingest. A restricted page is not admitted, rather than admitted and hidden later.
- An answer with no citation is not shown. Where nothing clears the relevance floor, Memoria says it does not know instead of assembling something plausible from near-misses.
Stated limits
What we will not claim.
A specification that implies completeness it does not have is worse than one that admits its edges.
- Named-entity recognition is not configured by default. Person, tenant and market-sensitive suppression rests on the configured actor and tenant tables, pattern detectors and prompt text. The system logs this limitation at start-up rather than implying a guarantee.
- Signum never notifies a regulator. It computes the deadline per configured regime and reports elapsed or due. A named human decides and notifies.
- Retention defaults to seven years, configurable upward and never silently downward.
- Causa holds incident content in one case only. An ITSM ticket has a finite attachment budget. When it is full, Signum will not delete an earlier revision to make room: a transcript cannot be regenerated afterwards, because a message edited or deleted in Slack is gone from Slack, so an old attachment may be the only surviving record of what was said. The remaining revisions are therefore kept in Signum for reference and storage, the index records where each revision lives, and the ticket carries a notice stating that it no longer holds the whole conversation. Below that limit, and on platforms with no practical limit, Causa stores no incident content at all.
- Memoria keeps an index, and the files stay yours. Pages live in a Git repository you control. What Signum holds is an index derived from them — rebuildable by cloning the repository and running a sync — plus an append-only audit log of who asked what. The retrieval quality of that index does not yet meet its own published gate, and the numbers are on the platform page rather than in a footnote.
- Certification is roadmap, not held. Where a control is planned rather than in place, this site says so on the page rather than in a footnote.