Skip to content
CV Rocket
Get started
How it worksThe enginePricingBlogContactSign in

Open nowPosted 4 days agoWe saw it 107 min after it went up

Langfuse - Senior Software Engineer, SDK

ClickHouse202 open roles

Pay
€90,000 – €160,000 a year
Where
Germany
Work mode
Hybrid
Get the CV for this job

From $25 per CV, paid once. No subscription.

Your applicationOpen nowLangfuse - Senior Software Engineer, SDKClickHouse · Germany

  1. YouYes, apply to this one.

  2. CV RocketCV written for this posting.

  3. 25 readersRecruiter, hiring manager, skeptic. Round after round.

  4. CV RocketApplied on ClickHouse's own form.

The reply lands in your private mailbox

3×more interviews than doing it yourself with ChatGPT.

The clock on this job

Early applications get read.

11.8% of postings close within 7 days. Measured by our own scanner across the market. ClickHouse postings stay open a median of 27 days.

Share of postings closed within
  1. 2.1%1 day
  2. 4.4%3 days
  3. 11.8%7 days
  4. 18.6%14 days
  5. 35.6%30 days
  6. 45.1%60 days
This job: posted 4 days ago

ClickHouse median: 27 days open

The posting

WHY SDK ENGINEERING AT LANGFUSE

YOUR WORK WILL HAVE AN OUTSIZED IMPACT.

Our SDKs are downloaded 26M+ times per month. When you ship a new integration or improve SDK performance, thousands of developers benefit the same day — and they'll tell you about it in GitHub issues, on Twitter, and in our community channels. Everything you build is open source (MIT-licensed) and immediately visible.

The SDK is often the very first thing a developer touches when they try Langfuse, so your work directly shapes their first impression.

You will also have direct exposure to how cutting-edge LLM-applications are built. The users you serve are some of the best and most ambitious software engineers in the world and that leverage Langfuse to improve their applications. Deeply understanding the problems they solve will help you design the best possible SDK experience and along the way makes you an expert on LLM engineering yourself.

YOU WILL GROW AT LANGFUSE BY

- Owning our SDKs. We maintain SDKs in Python and TypeScript both built on OpenTelemetry. You'll be responsible for their reliability, performance, and developer experience. These SDKs run inside our users' production systems, which means they must never fail, must have minimal impact on CPU and memory, and must work flawlessly across every environment — from serverless functions to long-running agent loops. You'll think deeply about the exposed interfaces, error handling, batching, async flushing, and graceful degradation.

- Designing APIs that developers love. How are functions named, how are parameters structured, how are breaking changes communicated, how does the documentation read? Developer experience is a core differentiator for Langfuse and you'll own every detail of it. When we shipped the Python SDK v3 https://langfuse.com/changelog/2025-06-05-python-sdk-v3-generally-available and TypeScript SDK v4 https://langfuse.com/changelog/2025-08-28-typescript-sdk-v4-ga, both were full rewrites on OpenTelemetry — that's the kind of thoughtful, high-impact SDK work you'll lead. Apart from tracing, we also support core workflows of engineers building with LLMs with our SDKs, see our Experiment Runner SDK https://langfuse.com/docs/evaluation/experiments/experiments-via-sdk#experiment-runner-sdk for example.

- Integrating with every major AI framework: Langfuse integrates with 40+ frameworks and model providers: OpenAI SDK, Vercel AI SDK, AI SDK, LangChain, LlamaIndex, Pydantic AI, OpenAI Agents, CrewAI, Amazon Bedrock AgentCore, LiveKit, and many more. You'll maintain these integrations, ensure new Langfuse features are supported across all of them, and add new integrations as the ecosystem evolves. When a new framework gains traction, you'll be among the first to instrument it.

- Maintaining our OpenTelemetry endpoint: some users send traces directly to our OTLP endpoint https://opentelemetry.io/docs/specs/otlp/ instead of using our SDKs. You'll ensure this path is robust, well-documented, and supports the full range of Langfuse features. This also extends our language support to Java, Go, and any language with an OpenTelemetry SDK. You can work with the OpenTelemetry community to steer the GenAI conventions.

- Writing public documentation: you'll own the SDK docs, integration guides, and migration paths. At Langfuse, docs are part of our core product. When you ship a new SDK version or integration, the docs ship with it.

WHAT WE'RE LOOKING FOR

- Strong engineer who gets excited about developer experience, API design, and writing code that runs reliably in other people's production systems

- Experience building or maintaining SDKs, client libraries, or developer tools — ideally in Python and/or TypeScript

- Deep understanding of performance: you know how to profile, benchmark, and minimize CPU/memory overhead in hot paths

- Someone who can manage projects themselves — you know how to develop strong conviction about what to build and how to ship it

- Thoughtful about versioning, backwards compatibility, and migration paths

- Interest in open source software and genuine excitement about talking to developers about their integration challenges

- Thrives in a small, accountable team where your output is visible and matters

- CS or quantitative degree preferred

Bonus points:

- Experience with OpenTelemetry internals or observability instrumentation

- Former founder or early startup experience

- Contributions to popular open source SDKs or developer tools

- ML/AI background or familiarity with the LLM framework ecosystem

No candidate checks all boxes. If you feel you are a good fit for this role, please go ahead and apply.

LEARN MORE ABOUT

- SDK Overview https://langfuse.com/docs/observability/sdk/overview — architecture and design of our Python and TypeScript SDKs

- All Integrations https://langfuse.com/integrations — the full list of frameworks, model providers, and gateways we support

- OpenTelemetry Integration https://langfuse.com/integrations/native/opentelemetry — how we use OTEL as the foundation

- SDK Upgrade Paths https://langfuse.com/docs/observability/sdk/upgrade-path — how we think about versioning and breaking changes

- Project you could have built: TypeScript SDK v4 (GA) https://langfuse.com/changelog/2025-08-28-typescript-sdk-v4-ga

- Project you could have built: Python SDK v3 (GA) https://langfuse.com/changelog/2025-06-05-python-sdk-v3-generally-available

- Our codebase: GitHub Repository https://github.com/langfuse/langfuse/

- Ben Kuhn on Impact, Agency and Taste https://www.benkuhn.net/impact/

- Who we are & how we work https://langfuse.com/careers

PERKS

- Flexible work environment - ClickHouse is a globally distributed company and remote-friendly. We currently operate in over 25 countries.

- Healthcare - Employer contributions towards your healthcare.

- Equity in the company - Every new team member who joins our company receives stock options.

- Time off - Flexible time off in the US, generous entitlement in other countries.

- A USD$500 Home office setup if you’re a remote employee.

- Global Gatherings – We believe in the power of in-person connection and offer opportunities to engage with colleagues at company-wide offsites.

CULTURE - WE ALL SHAPE IT

As part of a rapidly scaling start-up, you will be instrumental in shaping our culture.

Are you interested in finding out more about our culture? Learn more about our values here https://clickhouse.com/company/careers. Check out our blog posts https://clickhouse.com/blog or follow us on LinkedIn https://www.linkedin.com/company/clickhouseinc/life/0c1ee7f4-2129-488d-b413-e7f6270659fd/?viewAsMember=true to find out more about what’s happening at ClickHouse.

EQUAL OPPORTUNITY & PRIVACY

ClickHouse provides equal employment opportunities to all employees and applicants and prohibits discrimination and harassment of any type based on factors such as race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws.

Please see here https://clickhouse.com/legal/applicant-privacy-notice for our Privacy Statement.

From $25, paid onceGet the CV for this job

What happens when you press

One press. We do the rest.

  1. A CV for this posting

    Written against ClickHouse's own wording, from every piece of relevant proof in your profile.

  2. 25 readers review it

    Recruiter, hiring manager, skeptic and more read every draft, round after round. You get the best round.

    The review screen in CV Rocket: how each CV was read, round by round.

  3. We apply on ClickHouse's form

    Our application engine gets through the hardest forms there are. Where a question needs you, AI suggests the best answer. Don't want us applying from our IP addresses? Use our Chrome extension: we apply straight from your own browser.

    An application in CV Rocket: every answer filled in on the employer's form.

  4. Every reply, sorted

    ClickHouse's answer lands in your private mailbox, and we classify it on arrival: interview, question, rejection.

    The CV Rocket inbox: each employer reply classified as an interview, an action or a rejection.

  5. Reply with AI

    AI helps you write the email, checks it and sends it. We show you whether the recruiter read it.

  6. The interview in your calendar

    Full integration with your calendar. The invitation goes straight in.

    An interview invitation in the CV Rocket inbox, added to the candidate's calendar.
Get the CV for this job

From $25 per CV, paid once. No subscription.

Why it works

3×

more interviews than doing it yourself with ChatGPT.

ChatGPT writes a CV and never learns what happened to it. We see every reply. For each CV we know:

  • How it was written, and how the review scored it
  • When we applied, and how long after the posting went up
  • Which posting, which company, which city
  • Who got the interview, and who heard nothing

That is how we know which CVs get called.

Get the CV for this job

From $25 per CV, paid once. No subscription.

The numbers game

More applications. More interviews.

Every application goes out with its own CV, written for that posting and paid once. Send enough of them and the law of large numbers finds you the job.

Get the CV for this job
By hand5–10
With CV Rocket100
applications a day

Nearby

Live postings like this one

Same employer first, then the same role elsewhere.

Before you press

Straight answers

Get the CV for this job

From $25 per CV, paid once. No subscription.

What if my background isn't good enough?

We make the most of the background you have. The CV uses every piece of relevant proof your profile holds, and one of the 25 readers reads your whole profile and flags what the CV left out.

Do you really apply for me?

Yes, on the employer's own form, the hardest ones included. Where a question needs you, you answer it right there and AI suggests the best answer. Don't want us applying from our IP addresses? Use our Chrome extension: we apply straight from your own browser.

Is it a subscription?

No. You pay once per CV, from $25. Every application goes out with its own CV, written for that posting.

One job. One CV.
Paid once.

Pick the posting you want. We write for it, apply for you and catch the reply.

Get the CV for this job

From $25 per CV, paid once. No subscription.