01
Before trust changes
Credible end-to-end encrypted communication with bounded server power and metadata.
Founder search open | Private V0 | Public V1 gated
Technical Cofounder
Build secure communication for the moment trust changes.
Quertius is looking for a genuine technical cofounder to own the architecture and help build a new category around control of future decryptability — not just protection in transit.
Founder-level equity | Remote-first | UK/European time-zone compatibility preferred
Current status: the website and V0 are privately published for controlled review. Public V1 is not launched, audited or certified.
The problem
Why Quertius exists
Encryption is essential, but secure delivery is not the end of the risk. Devices are lost or inspected. Trust in a person, role or endpoint can change. A second device, export, backup or support route can widen access. Once information has been delivered, ordinary messaging systems are largely designed for access to persist.
Quertius is being built around a different question: who should still be able to decrypt information later?
The model
Control across the trust lifecycle
02
While conditions are uncertain
Profiles, Restricted Unlock, Travel Mode and selective device scope reduce the readable surface.
03
After trust breaks
Message, chat, profile, device and reset actions change future decryptability at the right scope.
The hard boundaries matter: no central decryptability, no usable key escrow, no hidden recovery of destroyed keys, no admin message visibility, no export bypass and no promise that software can undo screenshots, already-seen plaintext or a fully compromised operating system.
Current state
Where the product is now
- A privately published V0 exists as the current controlled review surface.
- The static prototype has been frozen rather than mistaken for the live product.
- The product, architecture, protocol, state, trust-boundary, legal and assurance source pack is materially developed.
- Independent design-stage review is being sourced before trust-critical implementation is treated as cleared.
- The next stage needs a founder-level technical owner who can challenge the existing work, narrow it where needed and make it real.
The role
What you will own
01
Secure messaging architecture and the path from private V0 to the smallest credible V1.
02
Client-side key custody, access states, irreversible control actions and multi-device restrictive convergence.
03
Mobile and endpoint behaviour, relay and metadata boundaries, state-bound exports and support/read paths.
04
Infrastructure, environments, CI/CD, build provenance, secrets, signing separation and rollback/downgrade controls.
05
Technical evidence for independent review and the remediation work that follows.
06
Early technical hiring, engineering standards and the company's ability to say only what the evidence supports.
Assurance
Independent review and internal assurance
The technical cofounder will be Quertius's internal architecture and assurance owner. You will prepare evidence, support independent reviewers, answer technical questions and own remediation. You will not replace the external reviewer, issue the independent recommendation or control the reviewer's conclusions. We see that separation as a strength.
The person
Who we are looking for
- A hands-on technical founder or senior builder with deep product judgement.
- Experience in secure mobile systems, encrypted collaboration, applied cryptography, distributed systems, platform security or release integrity.
- Comfort with formal reasoning and threat modelling without mistaking models for implementation proof.
- A calm communicator who can explain hard boundaries to users, reviewers, investors and enterprise stakeholders.
- Someone who wants long-term ownership and is willing to narrow scope rather than weaken the trust model.
Terms
Founder package
This is a genuine cofounder role. A substantial founder-level equity package is anticipated, with modest pre-funding cash and a clearer salary path after financing. Final terms will reflect contribution, timing, cash, vesting, existing founder ownership, the planned financing and the agreed cap table. Board or director status will be considered separately as the relationship and structure are formalised.
How it works
The recruitment process
- 1
A direct founder conversation about the problem, the role and working style.
- 2
Mutual technical and founder diligence using public-safe material first.
- 3
Controlled access to the private website, V0 and selected technical materials for serious candidates.
- 4
References, conflict/IP review and, where useful, a separately agreed paid working session.
- 5
Cofounder, vesting, equity, cash, IP and governance documentation with specialist advice.
Apply
Start a founder conversation
Send a concise note to Hello@Quertius.com explaining why the problem matters to you, the systems you have built or owned, and a technical or product decision where you chose principle over convenience.
Selected candidates may receive controlled access to private materials. Nothing on this page represents public V1 availability, completed external review, audit, certification, a binding equity offer or a final cofounder agreement.
Questions
Candidate FAQ
No. It is intended as a genuine founder-level role with hands-on architecture and build ownership, not an early management title.
No. Quertius has a private website and private V0 for controlled review. Public V1 remains gated.
Not necessarily. You need strong secure-systems judgement, the ability to use established cryptography responsibly, and the discipline to bring in independent specialists where needed.
No. You would own internal technical readiness and remediation. The external reviewer remains independent.
Serious candidates can receive controlled, versioned access after an initial founder conversation and appropriate confidentiality and access checks.
The working model is remote-first, with UK/European time-zone compatibility preferred and regular founder working sessions by agreement.