Senior Software Engineer - Systems Integration

Arbisoft is hiring this role for a client project that builds software sitting inside CAD and desktop engineering tools, think plugins that load inside applications like SolidWorks or CATIA, open a local communication channel, and let external systems talk to them in real time. There are already 25 to 30 integrations in place and the list keeps growing. Each one needs to be built properly, maintained as tools update, and iterated on over time. We need someone senior who can own this independently, technically and with the client.

What you'll actually be doing

• Designing integration architecture across multiple CAD and desktop tools making the right structural decisions from the start and owning them when someone asks why
• Building and maintaining plugin bridges for Windows-based CAD and engineering tools
• Setting up local communication channels, WebSockets, HTTP, gRPC, named pipes, whatever fits
• Handling JSON message passing and executing code within host application environments
• Keeping existing integrations alive as vendors push updates that break things
• Designing how AI agents interact with these tools, not just exposing APIs but thinking through interaction patterns that hold up in production
• Engaging directly with the client presenting solutions, answering technical questions live, and defending your architectural choices confidently

What you need to bring

• 5+ years of solid engineering experience with strong system architecture depth, you've designed systems, not just built features
• You can look at a complex integration problem, map out the solution architecture, evaluate alternatives, and clearly explain why you went the direction you did
• Comfortable across multiple languages. Python is the main one and JavaScript are a plus
• Experience with IPC — WebSockets, gRPC, named pipes, HTTP servers, you know the drill
• Have built plugins or extensions for desktop apps before IDE extensions, CAD plugins, anything that loads inside a host application
• Windows debugging experience runtime issues, environment quirks, the works
• Client-facing experience, you're comfortable presenting to technical stakeholders, handling direct questions, and holding your ground in a conversation

Before You Apply: They're European, move fast, and ask hard questions. They want to know why you made a decision, what else you considered, and why you ruled it out. If that kind of environment energizes you, great. If not, this probably isn't the right fit.

Nice to have

• Familiarity with CAD tools and their APIs
• Knowledge of CATScript, VBScript, or similar proprietary languages
• Background in AI agent orchestration or LLM tool-use