I applied through other source. I interviewed at Lightspeed (Montreal, QC) in Feb 2026
Interview
The recruiter called me for a screening call, and suggested a different role, which I expressed enthusiasm in. The next day they sent me a generic email saying that I'm not a good fit for either role. Process seemed highly disorganized and was a waste of time.
I applied online. I interviewed at Lightspeed (Berlin) in Feb 2026
Interview
The process started with an initial screening round, followed by a technical interview with system design and then a round with deeper technical discussion with code review. The team was professional and direct throughout the process. Communication from HR was clear and timely.
The interviews were heavily focused on core Python fundamentals, concurrency concepts, messaging systems (queues, Kafka/RabbitMQ), transactions, and system design. The technical depth expected was quite high, especially around language-level concepts such as context managers, decorators, and concurrency primitives.
In the later round, the discussion became very detailed around Python internals and low-level constructs. When I wasn’t able to confidently explain a specific core concept (context managers), the interview was concluded early with the feedback that for a Senior role, strong fluency in core Python fundamentals is expected.
What I liked:
Interviewers were technically strong and clearly knowledgeable.
Questions were practical and relevant to backend engineering.
Clear feedback was given directly.
What could be improved:
The process felt somewhat unforgiving; the interview was ended early based on one foundational gap rather than evaluating overall system design and backend experience.
A slightly more holistic evaluation of seniority (architecture, real-world impact, problem-solving) alongside language fundamentals would make the process more balanced.
Interview questions [1]
Question 1
Decorators
Concurrency (GIL, threading vs multiprocessing)
Transactions and atomic operations
Messaging systems and delivery guarantees
I applied online. The process took 2 weeks. I interviewed at Lightspeed (Berlin) in Sep 2025
Interview
The process was straightforward. Everything was transparent throughout the process and I'l like to thank the recruiter Alan for being in the corner in the hiring journey.
For each round, I received briefs and guides on how to prepare. Overall, the process took 2 weeks. I didn't get the job, but received a detailed feedback in an online session.
Interview questions [1]
Question 1
What was your process in color selection and visual identity direction?