Senior Software Engineer, Channels

About the role

Altacee's Channels team owns the delivery layer — the infrastructure that moves messages from our orchestration engine into email, SMS, push, WhatsApp, RCS, and voice endpoints at scale. We process north of 100 million events per day across production tenants, and we run our own SMTP infrastructure alongside managed relationships with ISPs, MNOs, and channel platform APIs.

As a Senior Software Engineer on this team you'll own large, well-scoped features end-to-end: design, implementation, testing, observability, and on-call. You'll work closely with the Infrastructure team on the delivery pipeline and with the Product team on channel-facing features. This is not a "work on tickets" role — we expect senior engineers to identify problems, propose solutions, and drive them to completion with minimal direction.

What you'll do

• Design and implement high-throughput message dispatch pipelines in TypeScript and Go, with a focus on reliability, ordering guarantees, and back-pressure handling.
• Own the integration layer for new channel APIs (WhatsApp Business API, RCS via Jibe, AMP for Email) — including authentication flows, rate-limit handling, webhook ingestion, and delivery receipt reconciliation.
• Build and maintain the SMTP sending infrastructure: MTA configuration, IP pool management, bounce processing, and feedback loop parsing.
• Contribute to the deliverability scoring system — integrating signals from Google Postmaster Tools, ISP feedback loops, and DMARC aggregate reports into actionable dashboards and alerts.
• Write comprehensive tests (unit, integration, load) and maintain clear runbooks for the systems you own.
• Participate in the on-call rotation (approximately 1 week in 8) and drive blameless post-mortems for any incidents in your area.
• Mentor junior and mid-level engineers through code review and design discussions.

What we're looking for

• 5+ years of backend engineering experience with a track record of shipping production systems at scale.
• Strong TypeScript or Go skills (we use both; Go for hot-path pipeline work, TypeScript for API services and tooling).
• Hands-on experience with message queues and event-driven architectures (Kafka, SQS, Pub/Sub, or equivalent).
• Understanding of email delivery infrastructure: SMTP, DKIM, SPF, DMARC, bounce handling, feedback loops.
• Comfort with distributed systems trade-offs: consistency vs. availability, at-least-once vs. exactly-once delivery, idempotency patterns.
• Strong written communication — our team is async-first and design documents are the primary medium for technical alignment.

Nice to have

• Direct experience operating SMTP infrastructure (Postfix, Haraka, PowerMTA).
• Familiarity with WhatsApp Business API, RCS, or AMP for Email specs.
• Experience with multi-tenant SaaS — data isolation, per-tenant rate limiting.
• Contributions to open-source projects in the messaging or deliverability space.

Compensation

We pay at or above market for senior engineers in your location. Bands are location-adjusted; we don't apply arbitrary geographic penalties beyond cost-of-market calibration.

All roles include equity (options, standard 4-year vest / 1-year cliff), health coverage, $2,000 learning budget, and the other benefits listed on our careers page.

How to apply

Send a short note and your CV or GitHub/LinkedIn to [email protected] with "Senior Software Engineer, Channels" in the subject line. We respond to every application within 5 business days.

Our process: async take-home (paid, 3-4 hours) → two technical conversations (design + code) → values conversation with a founder → offer.