Senior Software Engineer, Sandboxes (EU or East Coast Preferred)

Overview

Job Description

Responsibilities

• - Design, develop, and lead improvements to the sandboxes product across agent integration, tool permissions, and developer-facing workflows.
• - Investigate and resolve correctness, performance, and stability issues in the agent integration layer across macOS, Windows, and Linux.
• - Drive the reliability and performance of sandbox creation, session management, and teardown for AI agent workloads.
• - Collaborate with peers, Product, and adjacent teams to evolve the architecture as requirements grow.
• - Mentor engineers on the team and set the bar in design reviews and code reviews.
• - Engage with the open source and agentic development community around sandboxing, MCP, and related ecosystems.
• - Participate in on-call rotations and respond to critical stability issues affecting users.
• - Document your work clearly and share knowledge with the rest of the team.

Required Skills

• - 8+ years of software engineering experience, with demonstrated technical leadership on production systems at scale.
• - Bachelor''s degree in Computer Science, Engineering, or a related field, or equivalent practical experience.
• - Experience building developer tools, desktop applications, or runtime infrastructure used directly by developers.
• - Familiarity with the agentic software development ecosystem: how coding agents work and how tools like Claude Code, Codex, or similar agents interact with their environment.
• - Ability to reason about isolation and security boundaries: what a sandbox should and shouldn''t expose, and how to make safe defaults obvious to users.
• - Experience driving architecture and technical strategy across multiple engineers or teams.
• - Strong written and verbal communication skills.
• - Comfortable working with a high degree of autonomy in a remote-first environment.

Benefits

• - Freedom & flexibility; fit your work around your life
• - Designated quarterly Whaleness Days plus end of year Whaleness break
• - Home office setup; we want you comfortable while you work
• - 16 weeks of paid Parental leave (after 6 months of employment)
• - Technology stipend equivalent to $100 USD net/month
• - PTO plan that encourages you to take time to do the things you enjoy
• - Training stipend for conferences, courses and classes
• - Equity; we are a growing start-up and want all employees to have a share in the success of the company
• - Docker Swag
• - Medical benefits, retirement and holidays vary by country
• - Remote-first culture, with offices in Seattle and Paris