(Senior) Fullstack Engineer - Freelance

Netguru; Remote; PLN 120,000 - 180,000; Full time

Job summary

A leading digital commerce company is seeking a Senior Fullstack Engineer in Poland. The role involves managing the implementation of Instagram Login and navigating Meta's app approval process. Candidates should be fluent in Polish and English, with experience in OAuth 2.0 and the Instagram Graph API. The company offers 100% remote work with flexible hours, opportunities for continuous skill development, and engagement in challenging projects. Join the team to contribute to innovative digital solutions.

Benefits

100% remote work

Flexible hours

Team collaboration on challenging projects

Continuous skills development

Qualifications

• Ability to manage the entire process of Instagram Login implementation.
• Experience in managing verification cycles with Meta.
• Knowledge of OAuth strategy implementation for secure data access.

Responsibilities

• Owning the 'App Review' Process with Meta.
• Configuring the application environment in the Meta for Developers console.
• Implementing 'Login with Instagram' flow for influencer profiling.
• Guiding the client through Meta's policies.

Skills

Fluency in Polish

Fluency in English

OAuth 2.0

Instagram Graph API

Meta App Review experience

Tools

Passport.js

NextAuth.js

OmniAuth

JWT (JSONWebTokens)

OpenIDConnect (OIDC)

Facebook Login Kit

GDPR compliance basics

Job description

Netguru is a trusted partner in digital commerce. The company helps leading brands modernize B2B solutions, marketplaces, and retail ecosystems. Since 2008, it has empowered businesses with cutting‑edge technology, AI‑powered personalization, and world‑class engineering and design teams. A certified B Corporation®, Netguru is trusted by major brands including IKEA, VW, OLX, Delivery Hero, Żabka, Wolt, Careem, and Vinted.

How freelancing works at Netguru?

As a Netguru freelancer, you can choose what works well for you. You decide when, where, and how you work on projects and tasks.

We match you with work that fits your skills. Plus, you have access to various opportunities across different industries and companies. That means you will not only gain more experience, but also develop various skills.

But there's more. Netguru freelancers can benefit from full‑time collaboration and really be a part of the team.

So, are you ready to make an impact? Join Netguru, and let's build beautiful software together.

Currently we are looking for a Senior Fullstack Engineer who has successfully implemented Instagram Login before and can handle the entire process independently again.

Salary range: up to 160 PLN/h (on a B2B contract)

Engagement: fulltime

Working Hours: CET

Start date: 31.01.2026

Project duration: 2 months

Tasks & Responsibilities:

• Owning the 'App Review' Process: Managing the complete verification cycle with Meta (including creating required screencasts and writing scope justifications) to ensure the app is approved for Live access.
• Meta Ecosystem Configuration: Correctly setting up the application environment in the Meta for Developers console (identified by the client as the primary risk area).
• OAuth Strategy & Implementation: Implementing the 'Login with Instagram' flow to securely fetch specific influencer data points needed for profiling.
• Technical Advisory: Acting as the subject‑matter expert to guide the client through Meta's strict policies and prevent application rejection.

• fluency in Polish and English.
• OAuth 2.0.
• Instagram Graph API.
• Meta App Review experience.

Nice to have:

• Passport.js / NextAuth.js / OmniAuth (depending on stack).
• JWT (JSONWebTokens).
• OpenIDConnect (OIDC).
• Facebook Login Kit.
• GDPR compliance basics.

In return, we offer:

• 100% remote, flexible work.
• Work with an experienced team of developers and continuous development of your hard and soft skills.
• Dev‑friendly processes such as Continuous Integration, Continuous Delivery, Code Review and bug bashes.
• Long‑term collaboration on challenging products (FinTech, B2B software, E‑commerce and more).

Here's what you can expect from the recruitment process:

• First, you'll meet with one of our recruiters to get to know each other better.
• If everything goes well, you'll have the opportunity to meet with the client during an online interview.

Curious to learn more about working as a Netguru freelancer? All the information you need is here: Netguru Talent Marketplace.

Looking for a full‑time job? Check out our Career Page and find out more about our open recruitment processes.

If you need any disability‑related adaptation at any step of the recruitment process – simply let the recruiter know! We'd be happy to help.

Don't hesitate and apply right away.