Senior Backend Engineer, Backend Platform (PHP and Python)

Manychat, Inc; Barcelona; On-site; EUR 70,000 - 105,000; Full time

Job summary

Manychat, Inc is seeking a Senior Backend Engineer to own backend platform initiatives across PHP and Python. You will lead company-level projects, define ownership, and shape a unified backend platform, improving observability and performance while coordinating with multiple teams.

You’ll drive architecture decisions, write ADRs/Design Docs, and work on security-minded, scalable solutions for the Auth Service.

Qualifications

• Production backend experience in PHP or Python.
• Experience with high-load production systems and improving their performance.
• Design multi-component systems with clear boundaries, planning for failures, rollout, and rollback, with security in mind.
• Ability to write ADRs and Design Docs to explain trade-offs.

Responsibilities

• Lead company-level technical projects end to end, from design to rollout and support.
• Shape the shared PHP and Python platform and decide module placement.
• Build foundations for Python product launches and scaling without PHP wiring.
• Define ownership of technical components across the backend.
• Improve incident management, alerts, and dashboards (Grafana Cloud).
• Find root causes using metrics, logs, and distributed tracing.
• Incorporate performance metrics and architecture decisions for high load.

Skills

PHP

Python

Backend design

Observability

Distributed tracing

High-load systems

ADRs / design docs

Tools

Grafana Cloud

Rollbar

CI/CD

Job description

WHO WE ARE

Creating content that resonates is great — turning that attention into growth is even better. That's what Manychat does.

Our AI-powered automations help creators and brands engage with audiences across Instagram, Messenger, WhatsApp, and TikTok — at the right moment, with the right message, minus the manual work.

We're 400+ people across three continents behind the leading platform for conversational growth, with AI skills shaping how we build, how we work, and how we grow.

WHO WE'RE LOOKING FOR

Some engineers own a feature. On Backend Platform, you'll own how the backend works for everyone.

We're looking for a Senior Backend Engineer who works across PHP and Python and wants a say in the bigger picture. You'll lead company-level projects, like our Auth Service: one authorization layer for PHP and Python that lets Python products handle their traffic directly, without going through PHP. You'll research first when things are unclear, weigh the trade-offs, write them down, then ship in small, safe steps. And you'll decide where code should live by what makes sense for the system, not by which language you know best.

Product teams will come to you for advice, reviews, and a way through when they're stuck. The team is still taking shape, so you'll also help define ownership, standards, and how we work. If that mix of deep technical work and influence across teams sounds like you, keep reading.

YOUR FUTURE TEAMMATES

Meet the Backend Platform team:

We're a small team of engineers from core PHP, Infra, and AI backgrounds. We lead technical initiatives across the whole backend and own its health. Product teams build and run their own components, and we give them the tools, standards, and expertise to do it well. Each of us leads our own project, from planning to agreeing with other teams to production. We work in weekly cycles and write our decisions down. Right now we're bringing PHP and Python platform work together into one common backend platform.

WHAT YOU'LL DO

• Lead company-level technical projects end to end, from design and planning to rollout and support, like completing our Auth Service development and shaping authorization as a separate layer for PHP and Python.

• Shape the shared PHP and Python platform, and decide where each module should live by what makes sense for the system.

• Build the foundations that let new Python products launch and scale without being wired through PHP each time.

• Define clear ownership of technical components across the backend, including who owns monitoring and knowledge for each.

• Improve how we spot problems: bug and incident management, less noise in alerts and error tracking, and Grafana Cloud dashboards for how services interact.

• Find root causes across PHP and Python services using metrics, logs, and distributed tracing.

• Make performance part of everyday work, not something we fix after incidents: clear performance metrics, tools that show where things slow down, and analysis of unusual user behavior that causes degradation.

• Make architecture decisions with high load in mind, working with databases, servers, proxies, and DNS alongside the Infra team.

• Work with the Security team to fix vulnerabilities, build in security practices, and keep libraries and dependencies up to date.

• Improve developer experience: dev environment, CI/CD, routine automation, one documentation approach for PHP and Python, and tools for AI coding assistants.

• Turn product teams' requests into solutions: find what really hurts, propose the best fix, and support them with architecture advice and reviews in shared components.

TO SHINE IN THIS ROLE

You'll need:

• Production backend experience in PHP or Python, and the ability to read and work with the other. You'll write production code in both.

• Experience with high-load production systems and improving their performance.

• Experience designing multi-component systems with clear boundaries, planning for failures, rollout, and rollback, with security in mind.

• Experience comparing technical options, naming the trade-offs, and explaining your choice in writing (ADRs, Design Docs).

• Hands-on observability experience: metrics, dashboards, alerts, logs, and distributed tracing, and using them to find root causes.

• Experience leading a project that spans several teams: breaking it into small, testable steps, getting other teams on board, and taking it to production.

• A track record of improving engineering quality beyond your own tasks, for example setting up error monitoring or a process when things kept breaking.

• Enough infrastructure knowledge (databases, servers, proxies, DNS) to work well with Infra and see how your changes affect them.

• Clear communication: you explain your point of view, find the real problem behind a request, and flag risks early.

• Experience leading work independently while supporting your team: taking feedback, helping colleagues grow, and changing your mind when the arguments are good.

It would be great if you have:

• Experience on a Platform or Core team.

• Strong production experience in both PHP and Python.

• Experience with authentication and authorization systems (for example, JWT or Ory Oathkeeper).

• Experience defining SLOs and building symptom-based alerts.

• Experience running incidents and blameless post-mortems.

• Experience with Grafana Cloud, Rollbar, or similar tools.

• Experience building developer tooling, CI/CD, or tools for AI coding assistants.

• Experience mentoring engineers or leading knowledge sharing across teams.

Manychat is an Equal Opportunity Employer. We’re committed to building a diverse and inclusive team. We do not discriminate against qualified employees or applicants because of race, color, religion, gender identity, sex, sexual preference, sexual identity, pregnancy, national origin, ancestry, citizenship, age, marital status, physical disability, mental disability, medical condition, military status, or any other characteristic protected by local law or ordinance.

This commitment is also reflected through our candidate experience. If you have individual needs that may require an accommodation during the interview process, please indicate this in your application. We will do our best to provide assistance throughout your interview process to ensure you’re set up for success.