Hiring Senior Systems Engineer (Postfix, rspamd, Vault, AEAD) to build ISP-level message filtering prototyp

Job ID: 39981481

Budget: $750 – $1,500 AUD

Hiring: Senior Systems Engineer — Build ISP-Level Email Filtering Prototype (Postfix, rspamd, Vault, AEAD)

Remote • Contract (4–6 weeks) • Equity available

We are building the first working prototype of Scam.Security, an ISP-level scam/spam/malware prevention system that moves message filtering away from user devices and into the provider network. A patent is filed, and now we need an expert engineer to assemble the prototype using commercial off-the-shelf components.

What You Will Build

A fully operational ISP-style email pipeline demonstrating:

SMTP ingress (Postfix or Exim)

Filtering (rspamd + ClamAV)

Malicious quarantine inside ISP

AEAD envelope encryption (AES-GCM or ChaCha20-Poly1305)

Session key wrapping using Hashicorp Vault

Provider-signed provenance headers (PVD)

Remote attestation gate (mock version OK: challenge-response)

Client decryptor app (Python/Go/Rust)

Transparency log (append-only, hash-chained)

Full technical pack, diagrams, repository layout, and MVP plan provided.

Required Skills

You must have strong experience in:

Postfix or Exim (mandatory)

Email filtering (rspamd, SpamAssassin, ClamAV)

Linux system administration

Email transport internals (MTA/LDA)

Encryption basics (AEAD, key wrapping)

Hashicorp Vault or KMS equivalents

Python, Go, or Rust for pipeline glue

Nice to Have

DNSSEC / TLSA

HSM experience

ISP or carrier background

eBPF / DPDK

Post-quantum crypto familiarity

Deliverables

Running ISP-level filtering prototype

Quarantine engine

Encryption pipeline

PVD header injection

Key-unwrap attestation gate

Client decryptor

Transparency ledger

Demo scripts

Documentation + GitHub repo

Engagement Details

Contract: 4–6 weeks

Fully remote

Competitive compensation

Equity available for exceptional long-term engineer

Immediate start

To Apply

Please send:

Your experience with Postfix/Exim

Examples of relevant projects

Your approach to the build

Availability

Preferred compensation (fixed/hourly)

john.seymour