Lead Engineer (up to £130k)

Dex; Greater London; On-site; GBP 120,000 - 180,000; Full time

Job summary

Dex is partnering with a pre-seed venture building AI risk intelligence for large tender bids. You will join as the hands‑on engineering anchor alongside a serial founder CTO and an AI PhD, building core probabilistic risk models and full‑stack software deployed to live bids.

You will own the tech foundation, with a clear trajectory to CTO as you hire and scale the team, and you will engage directly with enterprise customers and investors as a key technical contributor.

Qualifications

• Deep full‑stack Python experience with production-grade deployments.
• Working background in probabilistic modelling or Monte Carlo simulation.
• Demonstrated early‑stage startup experience and end‑to‑end ownership.
• Strong communication skills for enterprise interactions.

Responsibilities

• Build multimodal representation pipelines from complex tender packs.
• Develop probabilistic risk models and Monte Carlo simulations.
• Own end‑to‑end full‑stack architecture in Python (data ingestion to UI).
• Drive feasibility testing, back‑testing, and live deployments on bids.
• Collaborate with design partners to translate risk workflows into production software.

Skills

Full-stack Python

LLM features

Probabilistic modelling

Monte Carlo simulations

Startup experience

Communication

Tools

Python

Job description

This role is with one of Dex's trusted partner companies. We work closely with their teams to truly understand their culture, goals, and what they're looking for, so we can match you with the right opportunity and give you context about the role before you commit to a process.

The role

Tier 1 contractors operate on razor‑thin 2‑4% margins, meaning a single mispriced tender can wipe out an entire year of profit. Almost all of that multi‑million‑pound risk is still calculated in spreadsheets. Backed by specialist global investors, this pre‑seed company is building AI risk intelligence that ingests multimodal tender packs—drawings, specifications, programmes, and contracts—and combines them with historic project data to price and track risk through delivery.

You will join as the hands‑on engineering anchor alongside a serial founding CTO and an AI PhD. This is not a speculative research role or a pure engineering manager seat where you coordinate sprints from a dashboard; you will build the core probabilistic risk models, Monte Carlo simulations, and full‑stack software deployed directly to live commercial bids. There is no team to manage on day one, but you will set the technical foundation with a clear trajectory to CTO as you hire and scale the team.

The work

• Build multimodal representation pipelines that extract and structure signal from complex tender packs, including technical drawings, schedules, and contractual terms.
• Develop probabilistic risk models and Monte Carlo simulations calibrated against historical commercial project data.
• Own the end‑to‑end full‑stack architecture in Python, from data ingestion and cloud infrastructure to the customer‑facing interface.
• Drive systems from feasibility testing on public datasets to live back‑testing and deployments on active contractor bids.
• Engage directly with commercial design partners to translate complex risk assessment workflows into robust production software.

What You Bring

• Deep full‑stack Python experience with a track record of deploying LLM‑powered features and data pipelines to production.
• Working background in probabilistic modelling, Monte Carlo simulation, or representation learning over unstructured data.
• Demonstrated early‑stage startup experience, comfortable taking total end‑to‑end architecture ownership without waiting for a playbook.
• Strong, clear communication skills with the confidence to interface directly with enterprise customers and investors.

Why apply through Dex

Founding‑level engineering roles with an explicit path to CTO are rarely advertised openly, and it is notoriously hard to distinguish real technical substance from thin wrappers at pre‑seed. Applying through Dex bypasses cold applications and gets you directly in front of the founding team with an upfront technical brief. One profile matches you across vetted, high‑ownership engineering roles across the market.

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