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Joko

Joko

Cashback shopping app with carbon tracking

AI Software Engineer

Full-TimeUpdated on 9/13/2026
€76.3k - €174.6k/yr

+ Equity

Senior
Bachelor's
Barcelona, Spain+1 more

More locations: Île-de-France, France

Remote

Remote within France or Spain.

About the job

Requirements
  • At least 5 years of software engineering experience, including experience building and shipping production systems.
  • Experience operating at a senior or staff level and owning ambitious projects from design through production.
  • Experience building production AI systems used by real users is preferred.
  • Strong focus on code quality, separation of concerns, and testing.
  • Deep familiarity with agentic frameworks such as LangChain, LangGraph, or equivalent tools.
  • Familiarity with LLM observability tools such as LangFuse or equivalent tools.
  • Familiarity with LLM application programming interfaces and evaluation tooling for AI systems.
  • Comfort working across AI logic, infrastructure, and frontend prototyping.
  • Fluency in written and spoken English.
Responsibilities
  • Own the development and continuous improvement of Joko AI, the company’s AI shopping agent.
  • Own the architecture of the agentic system and evolve it by incorporating advances, testing ideas, and improving the assistant’s capabilities.
  • Design and run evaluation frameworks to measure performance, detect regressions, and build confidence before production releases.
  • Expand the tools and capabilities available to Joko AI, including web search, vector search, and catalog lookups.
  • Ingest, standardize, and enrich a product catalog containing hundreds of millions of entries at scale, using AI where appropriate.
  • Use bank-transaction and browsing-behavior signals to understand user intent and build personalized experiences.
  • Identify challenges, prototype new agent features, release early versions to users, and iterate using real feedback.
  • Track emerging models, agentic frameworks, and research papers and translate them into improvements for Joko AI.
  • Fine-tune models to improve quality, reduce latency, and lower costs in production.
  • Iterate on the runtime backbone and infrastructure so Joko AI supports hundreds of thousands of daily users with high availability and low latency.
  • Collaborate with the Product team to define the AI-assisted shopping experience and deliver it from concept through rollout.
Desired Qualifications
  • An AI or machine-learning background or degree.
  • Experience building production AI systems that real users rely on.

About the company

Joko operates a mobile shopping app that gives users cashback, coupons, and discounts from a wide range of retailers. It earns commissions through affiliate marketing when users make purchases via the app. The app is free for users and automatically calculates the carbon footprint of each transaction, encouraging more conscious consumption. How it works: users browse partners in the app, activate deals, and make purchases through affiliate links to get rewards; the platform tracks sales and credits cashback automatically to the user’s account. How it is different: it combines traditional cashback and coupon offers with real-time carbon footprint insights for each purchase, offering environmental visibility alongside savings, within a broad consumer market. What the company aims for: to help people save money on everyday spending while promoting greener consumption and to grow its affiliate network across retailers.

Company Size

201-500

Company Stage

Series A

Total Funding

$12.8M

Headquarters

Paris, France

Founded

2018

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Simplify's Take

What believers are saying

  • The Play Store updated Joko on August 27, 2026, showing active product investment.
  • Third-party 2026 coverage claims 5 million users and 3,500 partners.
  • Daily boosted offers and gift-card cashback expand monetization beyond simple cashback.

What critics are saying

  • Joko depends on partner commissions; Booking.com, eBay, and Best Buy can squeeze payouts.
  • Open Banking and card-linking create fragile retention if banks tighten API permissions.
  • A policy shift from Apple or Google can choke installs and break attribution.

What makes Joko unique

  • Joko turns bank-card data into automatic cashback without manual offer activation.
  • Its 2026 app reaches 6,000 retailers, gift cards, and browser extension rewards.
  • Carbon-footprint tracking adds a rare sustainability layer to shopping rewards.

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Benefits

Flexible Work Hours

Remote Work Options

Phone/Internet Stipend

Gym Membership

Health Insurance

Meal Benefits

Growth & Insights and Company News

Headcount

6 month growth

-3%

1 year growth

-2%

2 year growth

5%
Medium
Jul 21st, 2021
Hellojoko launched version of the app on Jul 20th 21'.

Yesterday, Hellojoko released a new version of the app that makes it possible for you to shop on any website using Joko.

Silicon Canals
Oct 8th, 2020
This Paris based fintech startup rewards you for your everyday expenses; raises €10M

Joko, a mobile app that rewards its users every time they spend using its bank card raised €10M funding from Partech and Axeleo. Read more..

Tech.eu
Oct 8th, 2020
Paris-based fintech startup Joko seals €10 million Series A to expand cashback rewards program

Joko, a French fintech company aiming to disrupt cashback rewards, has raised a €10 million Series A round to begin expanding into other European countries. The funding comes from two French VCs, Partech and Axeleo, who also participated in a €1.6 million seed round last year. Based on the Open Data initiative enabled by the […]