Staff Backend Software Engineer - Performance

Vibe; Paris; Sur place; EUR 90 000 - 140 000; Plein temps

Avantages offerts par ce poste

Variable pay

Hybrid flexibility

Health insurance

Meal vouchers

Annual offsite

Tech Syncs

Résumé du poste

Vibe in Paris is seeking a backend performance engineer to own the pacer and bidder, improving CPx accuracy and win rate while helping scale critical knowledge across the team. You’ll shape auction dynamics and pacing in a fast-paced ad tech stack.

You will deepen probabilistic foundations, apply PID control concepts, and leverage AI tooling to ship measurable improvements in production. This is a hybrid Paris-based role with strong ownership expectations.

Qualifications

• Shipped backend systems in production-scale environments using a strongly typed language.
• Experience debugging distributed systems under real traffic, addressing latency and consistency.
• Familiarity with auction mechanics from the inside of DSP/SSP bidder ecosystems.
• Built or tuned pacing algorithms or PID controllers with theory and practical implementation.
• Solid grounding in probabilistic reasoning and statistical modelling.

Responsabilités

• Own the pacer and bidder, map end-to-end flow, identify fragilities on day one.
• Propose autonomous improvements to the bidder or pacer from problem definition to design.
• Ship measurable improvements to CPx, pacing accuracy, or win rate within three months.

Connaissances

C++, Rust, Go, Scala, Java

Distributed systems

Auction mechanics

PID controllers

Probabilistic modelling

Low-latency data

Real-time data pipelines

Redis

Kafka

Outils

Redis

Kafka

Description du poste

About the Role

You’ll join the Performance team the engineers who own advertiser outcomes at Vibe. Bidding, pacing, and the prediction stack that drives both. You’ll report to Clément Schiano, Engineering Manager for Performance.

This role exists because our roadmap is clear and the bottleneck is execution. We have a knowledge concentration problem too: critical expertise sits with one person, which creates fragility. We need someone who can absorb, challenge, and extend that knowledge not just ship tickets.

Three reasons someone great would want this job:

1. CTV performance advertising is still being invented. The auction dynamics, identity graph, and feedback loops are nothing like display or search. There's no playbook to copy you'd be writing it.

2. You own the full decision loop. From prediction to bid price to pacing, on a product real advertisers depend on today. Your judgment shapes the direction. You’ll see the impact in the numbers within weeks.

3. The timing is right. Past "does this work?" and into "how fast can we scale this?" Early enough to shape the architecture. Late enough that you're not building on sand.

What You’ll Do

Own the pacer and bidder

• Go deep on the bidder and pacer stack map it end-to-end and identify at least one fragility worth owning on day one

• Propose improvements to the bidder or pacer autonomously from problem definition through to design proposal

• Ship measurable improvements to CPx, pacing accuracy, or win rate within your first three months

Raise the team's ceiling

• Distribute critical system knowledge: make the team faster and less dependent on any single person

• Challenge existing designs, including inherited ones, and push for cleaner solutions

• Deepen expertise in the theoretical foundations (probabilistic modelling, PID control theory) powering our approaches

Move at Vibe pace

• Use AI tooling as a genuine force multiplier (not a crutch, not a checkbox)

• Iterate in production, not in your head, we - ship, measure and adjust

What You Need

• Shipped backend systems in a strongly typed language C++, Rust, Go, Scala, Java, or equivalent at production scale

• Debugged distributed systems under real traffic: latency issues, consistency failures, the works

• Worked inside a DSP, SSP, or bidder: you understand auction mechanics from the inside

• Built or tuned pacing algorithms or PID controllers theory and implementation, not just awareness

• Solid grounding in probabilistic reasoning and statistical modelling you think in distributions, not just averages

Nice to Haves

• Experience in a scale-up environment you know what fast and resource‑constrained actually feels like

• ML systems in production: feature pipelines, model serving (not just training notebooks)

• Real‑time data pipelines and low‑latency architectures at scale

• Redis, Kafka, or equivalent under meaningful load

Our Values

At Vibe, we run on three values: Impact, Ambition, and Urgency. We tie every goal to a real business outcome, think 10x rather than settling for good enough, and move daily rather than waiting for perfect conditions.

You’ll thrive here if you own outcomes without needing direction, default to action, and hold yourself to results, not effort.

This is a high‑performance environment with high‑performance rewards: you'll work alongside people who push you, with real ownership over hard problems in a market that's moving fast.

If that sounds like the best version of your career, we want to meet you.

What We Offer

• Variable pay — based on objectives you hit. No arbitrary targets.

• Hybrid flexibility — We're in the heart of Paris and our team is in 3x a week!

• Health insurance — Full coverage via Alan.

• Meal vouchers — Via Swile.

• Annual offsite — The whole team, once a year, somewhere worth the trip.

• Tech Syncs — Engineering and Product meet in person at least quarterly, worldwide.

Equal Opportunity

Vibe is an equal opportunity employer. We evaluate all applicants without regard to race, color, religion, national origin, gender, gender identity or expression, sexual orientation, age, disability, veteran status, or any other characteristic protected by law.

We believe the best ideas come from teams with different backgrounds, perspectives, and experiences. If you need a reasonable accommodation during the application or interview process, please let us know.