Product Engineer - m/w/d

charles

PLATFORM ENGINEER (M/W/D) PERMANENT EMPLOYEE, FULL-TIME · BERLIN (HYBRID)  THE IMPACT YOU WILL MAKE From socks, and petfood, to cosmetics, charles is helping countless brands reach their loyal customers every day, one conversation at a time. As a Platform Engineer at charles, you’ll help drive our product and infrastructure forward, enabling us to revolutionize conversational commerce. You’re a generalist with a passion for infrastructure and operations. You’ll work closely with the other Engineers to build scalable, high-performing systems, while improving system architecture, resolving tech debt, and ensuring seamless user experiences. Your contributions will result in reliable, data-driven solutions that support millions of users and push the boundaries of messaging-driven commerce. THIS IS WHAT YOU WILL BE DOING You'll build and operate our internal developer platform: the core services, APIs, and infrastructure that every product team builds on top of. That means writing software, not just configuring it, and standing up infrastructure that holds up under real production load. * You will be a part of a team that designs, develops, and operates the core services, APIs, and infrastructure that every product team builds on top of. Examples: building a billing API, maintaining Kubernetes operators, building an authentication broker, optimizing performance in our core monolith, and improving security in our link shortening service. * You will regularly partner with product teams to investigate issues, learn their use cases, and ship platform changes that hold up in production. * You'll join our on-call rotation as part of our "you build it, you run it" philosophy. * You'll have real room to drive cost and reliability initiatives that have measurable, company-wide impact. * You'll build the automations that make our whole software development lifecycle faster and more robust. YOU'LL FIT GREAT WITH THESE SKILLS AND VALUES * 3+ years of software engineering experience. You're a generalist - comfortable moving between writing a service, debugging infrastructure, and improving a pipeline in the same week. * You can build and ship production services in Go or TypeScript; not just scripts and glue. You also know Bash and have the judgment to pick the right tool instead of forcing your favorite one. * You can build and operate cloud infrastructure that survives real production workloads, ideally on GCP. * You've worked with GitHub Actions or similar CI/CD tools, and you know what a healthy and efficient pipeline looks like. * You have a solid grasp of scalable system design, distributed systems, cloud technologies, and how to roll out infrastructure changes. * You're comfortable with remote work and asynchronous communication. You also know that good collaboration needs visibility and cooperation, not just output. * You use AI tools effectively without handing over the steering wheel. * Product and business sense: you understand customer needs and focus on solving the right problems, not just building technically interesting solutions. * You're a self-directed learner. You don't need to know our whole stack on day one, but when you hit something unfamiliar, you dig in, ask good questions, and follow through. We'll give you room and context to grow; you bring the drive. Meeting all requirements is not necessary to apply. We encourage candidates who meet some but not all of these qualifications to submit their application. THINGS WE OFFER * Working on challenging and impactful projects at the forefront of one of the most innovative industries in Europe * Collaborating with some of the leading experts in Conversational Commerce and disrupting a fast-growing industry * Joining forces with a unique community of Tech, Product, Sales, Success, and Marketing experts committed to building the best product in Conversational Commerce. * High autonomy and visibility across the business with the option to own and drive new initiatives * Celebrating our major and micro-wins as well as getting to know each other better at regular team-building events * Sharing VSOP (virtual stock options) in the ownership and success of Charles * Working in a vibrant office in the heart of Berlin overlooking the Wall memorial * Flexible working model: Hybrid setup with remote work options and flexible hours * Earning a competitive compensation package What else we offer? * Urban Sports Club membership * Mental Health support through OpenUp * Free company lunch on Thursdays * A friendly, open, multicultural work environment * Dog-friendly office * Discounts on BVG tickets About us It’s better to have a conversation charles is a conversational AI and CRM for consumer brands that attracts, converts, services, and retains customers via AI agents, marketing automations, bulk campaigns, or an inbox for human agents. We help brands to maximize customer engagement and revenue through conversational channels such as WhatsApp. Businesses can reach customers in an interactive way, collect data to expand customer understanding and guide them to targeted offers that convert. charles’ AI Agents deliver hyperpersonalized experiences at scale while ensuring enterprise-grade security and GDPR compliance. Founded by Kapten & Son co-founder, Artjem Weissbeck, and ex-McKinsey ecommerce lead, Andreas Tussing. charles is backed by Salesforce Ventures, Accel and HV Capital and has raised over EUR 30 million to build the global leader in conversational marketing SaaS for global consumer brands. Charles and diversity: be yourself and no-one else Different perspectives bring innovation and richer work environments. We’re committed to building an inclusive company where you always feel like you belong, whatever your age, gender identity, ethnicity, religion, sexual orientation, disability, status or neurodiversity. These values sit at the heart of our hiring process, so we can create a welcoming workplace where everyone feels valued and heard.

Langdock

HELP US CHANGE THE WAY THE WORLD WORKS BUILD SOMETHING THAT MATTERS. Langdock exists to change the way the world works, bridging the gap between what technology can do and what people actually do with it. We bring all leading AI models into one secure, model-agnostic platform and make them usable across entire organizations. Over 6,000 companies use our platform every day, from fast-growing startups to some of Europe's largest enterprises. Their employees open Langdock to draft strategies, analyze documents, or automate workflows - helping them to work smarter, think more creatively, and reach their full potential. THE ROLE Platform Engineers at Langdock work on shared backend systems that many product features depend on. This includes the AI engine, queues, document processing, integrations, code execution, authentication, and billing. The job is to make these systems reliable and understandable enough that other engineers can build on them. That means designing clear APIs, choosing the right data models, handling failure cases, writing tests for important invariants, adding useful observability, and keeping abstractions simple enough to maintain. Typical problems include deciding which parts of a long conversation to keep in context, retrying background jobs without running the same side effect twice, handling model-provider failures during streaming responses, refreshing integration tokens before they expire, and enforcing tenant boundaries in shared services. WHAT YOU WILL WORK ON Examples of the kind of systems Platform Engineers own: * The AI engine at the core of the platform. It handles the prompts users send through Langdock and abstracts over providers such as OpenAI, Anthropic, Google, Azure, Bedrock, Mistral, and open-source models. The work includes prompt caching, routing, failover across model deployments, and normalizing provider-specific behavior behind a stable internal interface. * The workflow runtime. Workflows need to execute reliably across agent steps, conditions, loops, structured-output extraction, human-in-the-loop pauses, and actions across hundreds of integrations. The platform work is about making that execution model predictable, observable, and safe to extend. * Context-window optimization. Long conversations, uploaded files, and tool calls need to stay correct while model costs stay under control. This is one of the most cost-sensitive parts of the platform. * A code execution service for running untrusted customer code. Today this means JavaScript in some places, but the direction includes broader execution environments such as Bash. The hard part is clear isolation: secrets, filesystem access, outbound network access, and tenant boundaries need to be controlled explicitly. * A flexible integration layer for connecting Langdock to external services. Most integrations are standard REST APIs, but the platform also needs to support industry standards for tools and agents, including Model Context Protocol (MCP) and agent-to-agent (A2A) communication. You will pick up a platform area over time and can shape where it goes next. TECH STACK * TypeScript across a Turborepo monorepo * Next.js, React, and Tailwind on the front end * Node.js services and workers on the back end * PostgreSQL with Prisma; Redis with BullMQ * A multi-provider model abstraction across OpenAI, Anthropic, Google, Azure, Bedrock, Mistral, and open-source models * Sandboxed Node.js for code execution * Multi-cloud storage abstraction over AWS S3, Azure File Share, and GCS * Terraform for infrastructure orchestration * Kubernetes for workloads that need portable deployment across cloud providers * Linear for ticket management * Datadog and Sentry for observability You should be familiar with most of this. We trust you to pick up the rest quickly. HOW WE SHIP * Small temporary squads of 2 to 3 engineers around a topic. Squads form, ship, and dissolve. * Every change is linked to a Linear ticket and ships via PR. CI runs lint, tests, and AI review. * We deploy continuously to production. * We use AI tools heavily in engineering. You have freedom in the tools to use (eg. Cursor, Claude, Codex). We are building a strong harness that allows engineers to move fast while shipping high quality software. * We are building a strong operating system around AI-assisted shipping: clear ticket context, focused branches, AI review before human review, explicit rollout notes for risky changes, and production verification after release. * The engineer who ships a change owns it in production. If something breaks, you lead the fix. WHAT WE ARE LOOKING FOR * 3 to 6 years of experience building back-end systems that handle real load: queues, caches, databases, streaming pipelines, distributed schedulers. You can talk through failure modes and tradeoffs from systems you have actually run. * Strong in TypeScript and Node. Opinionated about API design, abstractions, and where boundaries should sit. * Some infrastructure experience: Terraform, Kubernetes, cloud deployments, networking, or operating services across AWS, Azure, or GCP. * Very driven. You have high standards for yourself, move fast without needing to be pushed, and want to do the best work of your career. * Working knowledge of the LLM ecosystem at a technical level: context windows, tool calling, streaming protocols, provider quirks, prompt caching. * Habit of adding metrics, traces, and structured logs because you have been on call before and know you will need them. * Security-first mindset. Multi-tenant data isolation is a design constraint, not a postscript. * Heavy user of AI tooling in your own development workflow, with opinions on what works and what does not. We are looking for people who are already compounding their output with AI. WORKING HERE We work from one office in Berlin, Greifswalder Str. 212. Engineering is fully in person; we believe the hardest problems get solved faster at a whiteboard than in a Slack thread. Most engineers start around 8:30. Lunch and dinner are together when people stay. Running and gym are part of the routine for many of us. COMPENSATION Top of market, transparent levels, all roles include equity. Levels are tied to scope, not negotiation or years of experience. We narrow down the range early in the process. NEXT STEPS If this sounds like your kind of work, we would like to meet you. We move fast. Most processes complete within two weeks.

Lumenaza

DAS SIND WIR Lumenaza entwickelt Software für die dezentrale Energiewelt. Unsere Plattform unterstützt Energieversorger, Erzeuger und Energiegemeinschaften bei der Abwicklung komplexer Prozesse in einem regulierten Marktumfeld. Mit dem Wachstum unserer Systeme wird Qualität zunehmend zu einer Frage von Verlässlichkeit, Transparenz und fundierten Entscheidungen – nicht nur zu einer Frage von Tests. Deine Rolle Wir suchen einen Senior QA Engineer (m/w/d), der unsere Qualitätssicherung auf das nächste Level hebt und dazu beiträgt, dass wir Software schneller, sicherer und mit höherer Verlässlichkeit ausliefern können. Du gestaltest unsere Qualitätsstrategie aktiv mit, entwickelst unsere Testlandschaft weiter und hilfst Teams dabei, Qualität frühzeitig in den Entwicklungsprozess zu integrieren. Der Erfolg dieser Rolle bemisst sich nicht an der Anzahl geschriebener Testfälle, sondern daran, wie gut wir Risiken erkennen, fundierte Release-Entscheidungen treffen und die Qualität unserer Systeme langfristig absichern. DEINE AUFGABEN Qualitätsstrategie und Testautomatisierung weiterentwickeln * Unsere Teststrategie über Unit-, Integrations-, API- und End-to-End-Tests hinweg weiterentwickeln * Testautomatisierung mit Fokus auf Wartbarkeit, Wiederverwendbarkeit und aussagekräftige Ergebnisse ausbauen * Teams dabei unterstützen, für unterschiedliche Risiken und Änderungen die passenden Testansätze zu wählen * Qualitätsmaßnahmen stärker in den Entwicklungsalltag integrieren und frühzeitige Validierung fördern Geschäftskritische Prozesse absichern * Ein tiefes Verständnis für unsere zentralen Markt- und Geschäftsprozesse aufbauen * Kritische End-to-End-Szenarien definieren und pflegen * Qualitätsrisiken in Services, Schnittstellen, Datenflüssen und Geschäftsprozessen identifizieren * Fehler analysieren, priorisieren und gemeinsam mit Engineering, Product und Operations nachhaltige Lösungen erarbeiten Release-Sicherheit und Transparenz schaffen * Releases hinsichtlich Qualität, Risiken und Testabdeckung bewerten * Teams bei fundierten Entscheidungen über Release-Freigaben unterstützen * Qualitätsmetriken, Testberichte und kontinuierliche Verbesserungsmaßnahmen vorantreiben * Erkenntnisse aus Tests, Incidents und dem Produktivbetrieb nutzen, um unsere Qualität kontinuierlich zu verbessern DEIN PROFIL Das solltest du mitbringen * Mehrjährige Erfahrung als Senior QA Engineer, SDET, Quality Engineer oder in einer vergleichbaren hands-on Rolle * Fundierte Erfahrung in der Testautomatisierung und modernen Softwareentwicklungsprozessen * Erfahrung mit Python und backendnahen Anwendungen * Erfahrung mit Docker, Docker Compose und containerisierten Testumgebungen * Erfahrung mit CI/CD-Pipelines und Linux-basierten Entwicklungsumgebungen * Ein gutes Gespür dafür, welche Risiken relevant sind und wie diese sinnvoll abgesichert werden können * Freude an der Zusammenarbeit mit Entwickler:innen und die Überzeugung, dass Qualität eine gemeinsame Verantwortung ist * Sehr gute Englischkenntnisse Das ist ein Plus * Erfahrung mit Django oder vergleichbaren Python-Webframeworks * Erfahrung mit Testdatenmanagement und Testumgebungen * Erfahrung in gewachsenen B2B- oder SaaS-Systemlandschaften * Deutschkenntnisse für die tägliche Zusammenarbeit * Erfahrung im deutschen Energiemarkt oder anderen stark prozessgetriebenen Branchen Warum diese Rolle spannend ist Qualität wird in modernen Softwareorganisationen immer wichtiger. Gerade in Zeiten von KI-gestützter Softwareentwicklung steigen Entwicklungsgeschwindigkeit und Veränderungsrate. Umso wichtiger werden verlässliche Qualitätssignale, eine gute Risikobewertung und fundierte Release-Entscheidungen. In dieser Rolle hast du die Möglichkeit, Qualitätsstandards organisationsweit mitzugestalten und direkten Einfluss auf die Zuverlässigkeit einer Plattform zu nehmen, die die Energiewende unterstützt. DAS BIETEN WIR DIR * Sinnstiftende Arbeit mit direktem Beitrag zur Energiewende * Eine sichtbare Rolle mit engem Austausch zwischen Engineering, Product und Operations * Viel Gestaltungsspielraum für Qualitätsprozesse und technische Verbesserungen * Hybrides Arbeiten mit Büro in Berlin * Faire Vergütung und attraktive Benefits, inklusive Deutschlandticket * Eine pragmatische und kollegiale Engineering-Kultur