Climate & Decisions is a Sydney-based advisory firm founded in 2024 by former Deloitte and SAP leaders. It is a member of the Stone & Chalk innovation hub.

We are building an enterprise software platform for large to medium organisations:

- Live in production on AWS. Enterprise customer onboarding starts in January 2027.
- Multi-tenant B2B SaaS. Each customer has an isolated environment.
- Independent engineering audit completed in October 2026. Its findings are your starting backlog.

About us

Climate & Decisions is a Sydney-based advisory firm founded in 2024 by former Deloitte and SAP leaders. It is a member of the Stone & Chalk innovation hub.

We are building an enterprise software platform for large to medium organisations:

- Live in production on AWS. Enterprise customer onboarding starts in January 2027.
- Multi-tenant B2B SaaS. Each customer has an isolated environment.
- Independent engineering audit completed in October 2026. Its findings are your starting backlog.
- Stack: Python / FastAPI, PostgreSQL with row-level security, vanilla JavaScript, AWS (ECS Fargate, RDS, Bedrock, CloudFormation), GitHub Actions.

We share product details after a mutual NDA.

What you’ll do before Christmas

By early December the critical fixes are done and the platform goes through a penetration test. By Christmas the foundations are signed off by you, ready for customers in January.

- Review the code and the audit. Read the codebase and the independent engineering audit. Confirm, re-prioritise and own the fix plan.
- Be the reviewer on every change. Review and approve all pull requests before they reach production.
- Harden security. Check tenant isolation (row-level security, database roles), login and MFA, roles and permissions, secrets, and the guardrails around AI features.
- Make releases safe. Set up database migrations, a staging setting, deployment checks, monitoring and alarms, and backups with a tested restore.
- Add automated checks. Security and dependency scanning in CI, alongside the existing tests.




- Prepare for the penetration test. Get the platform ready for an external penetration test in early December 2026, then fix what it finds.
- Document it. Write a short incident runbook and the security answers enterprise customers ask for.
- Plan 2027. Deliver a prioritised engineering roadmap for the next 6 months.

What you’ll bring

Must have

- 10+ years building and running production software, including multi-tenant B2B SaaS.
- Strong Python (FastAPI, Django or Flask) and PostgreSQL: row-level security, roles, migrations.
- AWS in production: ECS/Fargate, RDS, IAM, CloudFormation or similar infrastructure as code.
- Application security: OWASP Top 10, authentication and MFA, secrets management.
- CI/CD with GitHub Actions, and a disciplined pull‑request review practice.
- Comfortable working with tools like Claude Code.
- Explains technical risks clearly to a non-technical founder.
- Right to work in Australia.

Nice to have

- SOC 2 or ISO 27001 experience.
- Security of LLM features (prompt injection, data leakage), ideally on AWS Bedrock.
- Testing calculation-heavy or financial systems.
- Fractional CTO or technical advisor experience with startups building scalable SaaS solutions.

Beyond Christmas

There is a clear opportunity to continue part time in 2027, at about 1 day a week, as the platform's trusted technical owner.

- Remain the required reviewer on code changes and the security owner.
- Oversee the penetration retest and any remaining fixes.
- Run quarterly backup‑restore drills and dependency and security reviews.
- Give architecture guidance and light-touch review of a junior developer's work.
- Be on call as backup during customer go-lives.

As enterprise customers sign, the role can grow to 2–3 days a week or a fractional technical lead position.

Terms and how to apply

- Start: as soon as possible in November 2026.
- Rate: A$1,100–1,300 per day + GST, ABN contract, depending on experience.
- Before access: mutual NDA and IP assignment for work delivered.
- Working pattern: flexible days, with some overlap with Sydney business hours.

📌 Senior Software Engineer (Sydney)
🏢 Climate & Decisions
📍 Sydney