Senior Software Engineer - State Estimation

Company

Founded in 2020, Ribbit builds and operates autonomous airplanes. We develop technology that enables uncrewed gate-to-gate operations, having completed hundreds of autonomous flight hours on different aircraft, flown 10K+ hours in simulation, and secured flight authorities for remotely and optionally piloted flight. From defending sovereignty to delivering food and medical supplies, we are a trusted partner that businesses and governments rely on to test, operate, and deploy affordable autonomous aircraft. You can check out our videos here.

We believe that technology should be developed for and with the customer. In 2023, we signed our first federal contract with the Government of Canada, during which we performed Canada’s first autonomous gate-to-gate flight between two airports. Since then, we have won several additional contracts, including contracts with the National Research Council of Canada (NRC) and the Department of National Defence (DND) spanning platform, mission, and collaborative autonomy. We pride ourselves on knowing the customer better than themselves, serving them better than anyone else, and ensuring they succeed in a world with everyone else.

This year alone, we performed the world's first demonstration of collaborative teaming between an autonomous airplane and an autonomous helicopter. We also deployed Canada's first optionally piloted aircraft with a military callsign. We are now building novel autonomous aircraft for DND and Canada's allies, aligning our immediate defence clients with a backlog of interest across northern wholesalers, public safety agencies, freight forwarders, and humanitarian organizations. Autonomy is reshaping the way we move, understand, and protect the world.

Our team has years of experience with piloting, commercial drone operations, and autonomous mobile robotics—we're concentrating the world's best software, robotics, and aeronautical expertise to pursue our mission of making air transportation accessible to everyone. If you’re up for the challenge, we want to hear from you.

Position Overview

As a Senior State Estimation Engineer, you will collaborate with peers to:

• Lead development of the state estimation stack. You will shape its architecture and roadmap, lead design reviews, and hold the bar on code quality
• Research, design and develop the systems required for handling degraded or denied GNSS signals, ensuring a reliable aircraft state estimate when satellite navigation is jammed, spoofed, or unavailable
• Own the sensor suite deployed on our aircraft: from selection, calibration, time synchronisation, and health monitoring, to research into what new sensors the aircraft should carry next
• Stay hands-on: write production C++, review the handwritten code, and prototype/compare various estimation and sensing approaches
• Deploy tools for analyzing and providing quality metrics of state estimates for downstream users, establishing what the estimator can provide and the extent to which its outputs can be trusted
• Represent the estimation team in design reviews with the navigation, controls, hardware, and flight-test teams
• Onboard and mentor junior engineers that join the team

Your key objectives will include:

• Designing and implementing estimators that output the aircraft's state (e.g. EKF, error-state KF, UKF, factor-graph methods), including INS mechanisation,GNSS/INS integration
• Developing vision-based navigation that limits drift on long flights without GNSS, such as visual-inertial odometry, image-to-map matching, and landmark and runway detection
• Fusing a wide range of sensors: IMUs, multi-antenna GNSS, magnetometers, air data, barometric, radar and laser altimeters, cameras, and LiDAR
• Estimating wind, air data, and height above terrain accurately enough to support automatic takeoff, approach, flare, and landing
• Building fault detection and integrity monitoring into the estimator (e.g. innovation gating, cross-checks, jamming and spoofing detection, protection levels)
• Writing production C++ that runs in real time on the aircraft, tested against recorded flight logs, simulation, HIL, and flight

Other Details:

• No. of Positions: 1
• Duration: Permanent Full-Time, starting December 2026
• Compensation: 168000 to 183000 (includes base salary + equity + bonus)
• This is a remote role that involves some on-site presence to support field tests—you must be in the Greater Toronto Area/Hamilton/Kitchener/Waterloo or willing to relocate
• Competitive and comprehensive compensation (e.g. 3 weeks of vacation upon joining, comprehensive health and wellness plans)
• You must be eligible to hold a Government of Canada security clearance at the Reliability or Secret level, and pass security assessment for the Controlled Goods Program

Qualifications

As the ideal candidate, you meet the following requirements:

• A university degree in aerospace, electrical, mechanical, or software engineering, computer science, robotics, or a related field
• Experience developing state estimation or navigation software that has run on real hardware
• Modern C++ on Linux with Eigen, and estimation or vision libraries (e.g. GTSAM, Ceres, OpenCV)
• A strong foundation in probabilistic estimation: recursive and batch estimation techniques (linear/nonlinear Kalman filters and their variants), factor graphs, optimisation techniques, observability analysis, and covariance tuning
• Experience with inertial navigation systems and GNSS/INS integration, including IMU error modelling, attitude representations, and coordinate frames
• Experience developing state estimation/localization approaches without GNSS using alternative sensors, particularly vision (e.g. visual odometry, VIO, visual SLAM, map matching)
• Experience integrating and calibrating various sensors (e.g. intrinsics and extrinsic sensor calibration, time synchronisation, etc.)
• Python or MATLAB for analysis, filter tuning, and flight-log post-processing

Preferred and bonus qualifications include experience with:

• Developing and/or flight-testing autonomous aircraft or drones in a professional setting
• Aircraft-specific sensing modalities: air data, angle of attack and sideslip, wind estimation, and radar or laser altimetry
• Alternate methods for localizing/navigating without GNSS: terrain-referenced navigation, LiDAR localisation, or signals of opportunity
• Integrity monitoring (e.g. RAIM, protection levels) and detecting GNSS jamming and spoofing
• Commercial GNSS/INS units (e.g. NovAtel SPAN, VectorNav, SBG), or running vision on embedded or GPU hardware
• Safety-critical standards and processes (e.g. DO-178C, MISRA C++, static analysis)

You also possess the soft skills to work in a high-stakes, tight-knit company, such as:

• Openness to give and receive feedback
• Adaptability when priorities move
• Self-awareness about your own strengths and gaps
• Taking initiative with minimal guidance

Thank you for exploring opportunities at Ribbit! We look forward to speaking with you.

Note: the Careers page is under maintenance; actual details and interview process may differ slightly

Note: We read everything that comes our way. Let your outstanding résumé (cover letter and design portfolio encouraged but optional) do the talking. For important questions or comments, contact us at [email protected].