Mid Level Remote Software Developer Jobs in Toronto, ON

Remote Senior Desktop Software Developer

Sync.com is a leading end-to-end encrypted cloud storage platform operating at significant scale across dual data centers. We build secure, privacy-first software that millions of users trust with their most important files. Our desktop applications are the front line of that trust—running on Mac, Linux, and Windows, syncing data reliably and securely across every platform.

We're rebuilding our desktop application from the ground up. Our current clients are built on native, platform-specific stacks (C++/Swift and friends), and we're consolidating onto a unified, modern Rust-based architecture across macOS, Linux, and Windows—treated as first-class, equal targets.

We're looking for a Senior Desktop Software Developer to be the technical owner of this greenfield rewrite. This is a high-ownership individual contributor role: you'll architect the new application, define how we build and ship it, and set the engineering quality bar from day one. You won't have direct reports, but you will set the standard that the desktop product is measured against.

• Lead a greenfield rewrite of our desktop client, migrating from native platform-specific code to a unified Rust-based architecture.
• Own the complete desktop SDLC—architecture, implementation, release engineering, and ongoing maintenance—across macOS, Linux, and Windows as equal priorities.
• Tackle the genuinely hard problems end to end: sync engine internals, deep OS file-system integration, and robust update/release infrastructure—all of which we consider equally critical.
• Design and operate a secure auto-updater: signed delivery, signature verification, staged rollouts, rollback, and reliable cross-platform update mechanics.
• Define the quality bar for the new codebase from scratch—test strategy, automated coverage, CI/CD, observability, and crash reporting—and hold the product to it.
• Manage platform-specific concerns including code signing, notarization, packaging, background services, and native shell/file-system integrations.
• Integrate our existing end-to-end encryption layer into the client, ensuring cryptographic operations are correct, performant, and used safely.
• Use AI-assisted and agentic development tools (Claude Code, Codex, and similar) to accelerate delivery, and help establish best practices for AI-augmented workflows across the team.
• Collaborate with product, security, and backend teams to ship features that scale.

• Significant depth in desktop application development, with a track record of shipping and maintaining production software across macOS, Linux, and Windows.
• Strong proficiency in Rust, including async patterns, FFI, and performance optimization.
• Hands-on experience with cross-platform desktop frameworks such as Tauri and/or Electron.
• Experience leading or anchoring a significant rewrite or greenfield build—you've made the foundational architectural calls and lived with the consequences.
• Direct experience designing or operating auto-update systems, including secure distribution and code signing/notarization.
• Ability to define a testing and quality strategy from a blank slate, not just work within an existing one.
• Comfort integrating existing cryptographic libraries correctly; working understanding of E2EE concepts (AES-GCM, key management, client-side encryption).
• Comfort and fluency with AI coding tools and agentic workflows—you actively use them and understand their strengths and limits.
• Ownership mindset: you treat the desktop product as yours and drive it from architecture to shipped, supported software.

• Experience with cloud storage, file sync, or backup products.
• Familiarity with native APIs such as macOS File Provider, Windows Cloud Files API, or Linux FUSE.
• Background migrating off native C++/Swift codebases toward Rust.
• Experience contributing to or maintaining open-source Rust projects.

• Own a from-scratch rewrite of a core product surface—rare scope for an IC.
• Work on privacy-first software that genuinely protects users.
• High autonomy and real architectural influence.
• A team that embraces modern, AI-augmented engineering.
• Competitive compensation, benefits, and flexibility.

Compensation

• Base salary: CAD $160,000 – $175,000, depending on experience, skills, and location.

Benefits

• Comprehensive health benefits
• Flexible remote work
• Opportunity to lead the technical direction of a flagship desktop product
• High-impact work on a platform trusted by millions of users
• A profitable, privately held company investing in long-term product innovation