A.I. Engineer - Nullify

Black Nova Venture Capital; Sydney; On-site; AUD 90,000 - 130,000; Full time

Job summary

Black Nova Venture Capital seeks a software engineer to build and operate a robust agent runtime for vulnerability research. You will implement multi-provider flows, including loops, checkpoints, and governance, to enable reliable long-running runs.

You will design agents that reason about business logic and real application behavior, integrating tools and multi-step reasoning, while growing an evaluation harness with labelled test cases and regression tracking.

Qualifications

• Strong software engineering fundamentals in Go or Python.
• Experience building or operating LLM-based agents with tool use and multi-step reasoning.
• A scientist's instinct for measuring whether something actually works before shipping.

Responsibilities

• Build and harden agent runtime with multi-provider support (loops, structured output, checkpoint/resume).
• Design agents that reason about business logic and real app behavior, not just pattern matching.
• Grow evaluation harness with labelled test cases and regression tracking.
• Own agents end-to-end: detection, validation, fix generation, and the judgment calls in between.

Skills

Go

Python

Production systems

LLM-based agents

Multi-step reasoning

Job description

We're building the agent runtime that finds, validates, and prepares fixes for vulnerabilities automatically, while people retain judgment and merge control. That means solving real distributed-systems and reasoning problems, not gluing together prompts.

What You Do

• Build and harden Nullify's multi-provider agent runtime - turn loops, structured output, budget governance, checkpoint/resume for multi-hour runs.
• Design agents that reason about business logic and real application behavior, not just pattern-match against known signatures.
• Build and grow our evaluation harness - labelled test cases, scoring, regression tracking - so we can measure whether an agent got better or just got different.
• Own agents end-to-end: detection, validation, fix generation, and the judgment calls in between.

What You Bring

• Strong software engineering fundamentals - Go or Python, comfortable in production systems, not just notebooks.
• Experience building or operating LLM-based agents beyond a single prompt-response call: tool use, multi-step reasoning, retries, evals.
• A scientist's instinct for measuring whether something actually works before shipping it.
• Genuine interest in security - you don't need to be an expert yet, but you need to want to become one.