GTM Engineer in London

This role is London based, with 2 days per week in the office. But we are open to considering amazing talent across Europe to work remotely.

About Loctax: Loctax is a tax technology company. We build software for tax professionals at large multinationals — helping them with tax research, compliance, risk and governance management across all the jurisdictions they operate in. Founded in 2020, Loctax was acquired by Tax Systems in 2025 and is now part of the UK’s leading corporate tax software group, trusted by thousands of tax and finance professionals across enterprise organisations. Together with Tax Systems, we are building the very first Tax Operating System. One AI-powered platform where global tax teams can research, comply, and make decisions without switching between a dozen disconnected tools. This is an early and pivotal moment in that journey.

The Role: You will own and operate the entire go-to-market technical infrastructure for Loctax: the systems that discover, enrich, score, deduplicate, and route leads to the sales team. You will report to the Co-Founder (Growth) and work closely with the sales team and the CEO. This is not a traditional revenue or marketing ops role. You are building and maintaining custom data infrastructure: a Supabase backend, background workers, API integrations, social scraping pipelines, and a continuous dedup system. The majority of the code in this system can be built with AI-assisted coding tools like Claude Code, Cursor, or similar agentic development environments. What you need is a deep understanding of how data flows between systems, what constitutes a secure and GDPR-compliant architecture, and the ability to direct AI coding tools to build reliable, production-grade infrastructure. You are taking over a system built by an external operator and extending it significantly.

What You Will Own:

• Backend: Deploy and maintain the EU-hosted Postgres database that serves as the GTM system of record. Build and maintain the schema, API integrations, and data pipelines.
• Worker infrastructure: Write and deploy background workers (Node.js or Python) on Fly.io or Railway that handle enrichment, dedup, signal detection, social scraping, HubSpot sync, and outreach orchestration. Many workers embed AI via the Claude API for classification, scoring, and decision-making — you own the prompts, the structured output parsing, and the GDPR data-tiering that governs what data the AI sees.
• CRM deduplication: Own data quality across HubSpot. Implement continuous dedup on every new record. Maintain the company and contact matching logic. Handle edge cases around multinational corporate hierarchies.
• Signal architecture: Build and maintain the signal detection workers: LinkedIn engagement scraping, job change detection, marketing event parsing, connections-of automation, job posting routing.
• Email infrastructure: Set up and manage sending domains, DNS, warmup, suppression, and sequences in Lemlist for the mid-market pipeline.
• ICP scoring: Maintain and iterate on the scoring system. Currently in Clay; will migrate to Supabase workers.
• Sales Nav scraping: Manage the automated scraping of LinkedIn Sales Navigator for lead discovery and the connections-of signal.
• Analytics: Build closed-loop reporting: which signals, channels, and segments drive qualified meetings and revenue.

What You Will NOT Own:

• Product engineering: Loctax has a separate product engineering team of ~8 people. You do not build product features.
• Closing deals: The sales team handles all prospect conversations, demos, and deal management.
• Content creation: The marketing team creates content. You may help with distribution infrastructure.

Required Skills:

• Programming: Proficient in Node.js or Python. You will write workers, API integrations, and data transformation logic. This is not no-code.
• AI/LLM integration: Experience calling LLM APIs (Claude, GPT, etc.) programmatically from application code. You will build workers that use AI for classification, scoring, and reasoning — constructing structured prompts, parsing JSON responses, handling errors, and managing the boundary between what the AI decides and what the code enforces. This is not prompt engineering in a chat window; it is integrating AI as a component in a data pipeline.
• SQL: Strong Postgres SQL. You will write complex queries for dedup matching, signal detection, and reporting.
• API integrations: Experience building integrations with CRM APIs (HubSpot preferred), enrichment APIs, and social platform APIs. You understand rate limits, webhooks, pagination, and error handling.
• Infrastructure: Comfortable deploying and managing services on Fly.io, Railway, or similar. Docker basics. CI/CD. Monitoring and alerting.
• Data quality mindset: You care about dedup, data integrity, and suppression. You understand that sending a duplicate email to a CFO at a prospective customer is a serious problem, not a minor inconvenience.
• GDPR awareness: You understand the basics of GDPR data processing, legitimate interest, and data minimisation. You are working with EU prospect data and must handle it correctly.

Nice to Have:

• Web scraping: Experience with Playwright/Puppeteer, proxy rotation, session management. LinkedIn scraping experience is ideal.
• Clay: Experience with Clay.com as an enrichment tool. The system currently uses Clay and you will interact with it as an enrichment API.
• HubSpot workflows: Familiarity with HubSpot workflow automation, custom properties, and the CRM data model.
• B2B sales ops: Understanding of how sales teams work: pipeline stages, qualification frameworks (MEDDPICC), SDR workflows.

What we offer:

• Annual leave – enhanced holiday plus any local public holidays.
• Birthday day off.
• Competitive salary.
• Top tech gear.
• Learning budget.
• Bi-annual team offsites.