Senior Backend Engineer - JavaScript (AI-Fluent, B2B SaaS)

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TYPE OF WORK

Full Time

SALARY

N/A

HOURS PER WEEK

TBD

DATE UPDATED

Aug 5, 2026

JOB OVERVIEW

Job Description:

We're a US-based B2B SaaS company in the sales technology space. Our platform handles high-volume, real-time communication workloads for sales teams across the US. We're a small, fast-moving team. You'll have real ownership over core product systems from day one.

How we work - read this before applying. We ship fast and communicate constantly. Every engineer owns their issues end to end: you drive them to completion, you surface blockers within hours (not days), and you never let work sit silently. If you're stuck, you say so immediately and ask a sharp question. Getting unblocked fast is a skill we hire for. Asking early is a strength here, never a weakness. What doesn't work on this team: going quiet, letting an issue sit untouched, or waiting to be checked on. This is a full-time role and we expect full-time hours and full engagement. We won't micromanage your day, but your progress should be visible every single day through commits, PR activity, and updates, and we do pay attention to both the output and the time invested.

We are an AI-first engineering team with high standards. We use Claude (Claude Code and claude.ai) throughout our entire workflow: writing code, debugging production issues, reviewing PRs, drafting documentation, and investigating i ---------- . You must be fluent driving agentic AI coding tools through a real codebase. But fluency is only half the requirement. You must also be the kind of engineer who never blindly trusts AI output. You review every line before it ships. You understand exactly what the generated code does, what it touches, and what could break: race conditions, edge cases, security implications, performance costs. If the AI writes it and it breaks production, that's on you. If you don't use AI tools daily, this role is not a fit. If you use them as a copy-paste machine without understanding the output, this role is definitely not a fit.

What you'll work on:

- Building and maintaining backend APIs and services (JavaScript/Node.js and Python)
- Real-time, high-throughput product features where latency and reliability matter
- Third-party API integrations: webhooks, OAuth, data sync jobs
- Performance and reliability work: slow query hunting, race conditions, background job/queue tuning
- Cloud infrastructure operations and scaling

Must-haves:

- 4+ years professional backend experience with JavaScript/Node.js, plus working proficiency in Python
- A track record of independently driving issues to completion: you break down ambiguous problems, unblock yourself, and deliver on the timelines you commit to
- Fast, proactive communication: you flag blockers same-day and ask questions early instead of spinning
- Daily, fluent use of Claude Code or comparable agentic AI coding tools
- Proven ability to review, understand, and take full ownership of AI-generated code: you can explain every change in a PR and its downstream implications
- Strong database fluency across relational (MySQL), columnar/analytical (ClickHouse), and NoSQL databases: you can read a slow query log and fix the problem
- Experience with modern backend MVC frameworks
- Experience integrating third-party APIs and building webhook systems
- Comfortable debugging production issues independently: logs, metrics, tracing
- Strong written and spoken English
- Reliable internet and backup power (this is a production-critical role)

Nice-to-haves:

- Experience with real-time communication systems (VoIP, telephony, messaging, or streaming)
- Redis, job queues, event-driven architecture
- Cloud infrastructure experience (any major provider)
- Experience writing CLAUDE.md files, custom skills/commands, or MCP integrations

Schedule:

Remote, full-time on US business hours. Most of our team works US time and we collaborate live during the day, so you should expect to work a US-hours schedule. If that doesn't fit your life long term, this role isn't the right one.

How to apply:

Start your application with the word "BLUEPRINT" so we know you read this. Then include:

- A short note on the most complex production bug you've personally diagnosed and fixed (what it was and how you found it)
- A time you were assigned something ambiguous or outside your expertise. How did you get unstuck? How long did it take you to ask for help?
- A specific example of a time you caught a mistake, bug, or bad assumption in AI-generated code before it shipped. What did the AI get wrong and how did you spot it?
- Which AI tools you use daily. Describe your workflow.
- Links to code you've written (GitHub, or a description of relevant work)
- Your expected monthly salary and earliest start date

Applications that skip these questions or answer them generically will not be considered.

SKILL REQUIREMENT
Javascript API Development AI Automation
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