FH Solutions

Two backend-focused Ruby developers (1x Senior, 1x Mid)

Location: any

Start: ASAP

Duration: long-term (with potential extension)

Engagement: Full-time

English: B2+

We are looking for two backend-focused developers (1x Senior, 1x Mid) to join a 4-5 month project ASAP (with high potential for long-term extension).

The mission:

Extending the existing API to support self-service features for a new recruitment/hr application.

Requirements:

- Strong Ruby on Rails expertise: Deep experience in scaling and expanding API endpoints.

- React Native (Bonus): Skills in RN are a huge plus and will allow for more flexible task distribution.

- Availability: Ready to start immediately.

Recruitment Process:

1) Introductory Call (15 min): A quick chat to put a face to the name and discuss the role.

2) Case Study: A technical task with specific requirements. 
Note: This takes approximately 8 hours and must be completed within a 9 AM – 5 PM window.

3) Technical Interview: A deep dive into the case study.

4) Culture Fit Interview: A final conversation with the company's CEO

Looking for a Senior and Middle LLM engineers (ASAP)

Location: any

Start: ASAP

Duration: long-term (around 6 months)

Engagement: Full-time

English: B2+

Key Responsibilities:

We are looking for someone who can contribute further to our AgenticAI platform for construction. We need an LLM engineer who understands the following:

Design and implement deterministic workflows that ensure consistent, reliable outputs from LLMs

Solve fundamental challenges like making LLMs perform accurate mathematical operations (e.g., ensuring 1+1=2 consistently)

Build robust evaluation frameworks to measure and guarantee deterministic behaviorImplement comprehensive guardrails leveraging structured output and Pydantic models for input/output validation

Understanding of training dynamics, loss functions, and optimization strategies

Experience with parameter-efficient fine-tuning methods (LoRA, QLoRA, etc.)

Proficient in implementing and managing tool calling mechanisms

Deep understanding of Model Context Protocol (MCP) architecture and implementation

Experience in building and deploying LLM-powered applications using FastAPI/Flask and Streamlit for front-end interfaces, solid understanding of REST principles, HTTP Methods, websockets, and API lifecycle management;

Experience with SQL, NoSQL (PostgreSQL, MySQL, MongoDB, Redis), and vector databases (Pinecone, Weaviate, pgvector) for structured data storage and semantic search

Location: Germany (Hanover / Koblenz) or Remote

Format: Full-time

Duration: 6+ months

Start: ASAP

🚀 About the Project

We are looking for experienced Senior C++ Developers to join long-term projects focused on maintaining and modernizing large-scale on-premise systems.

These are mature products with complex legacy codebases (1M+ lines of code) that require deep technical expertise, strong ownership, and the ability to work with technical debt and system improvements.

🧩 Responsibilities

 • Work with large, complex C++ codebases (legacy systems)

 • Analyze and reduce technical debt

 • Implement system improvements and optimizations

 • Collaborate with distributed teams and stakeholders

 • Use AI tools to improve development efficiency and problem-solving

 • Take ownership of tasks and technical decisions

⸻

✅ Requirements

 • 5+ years of commercial experience with C++

 • Strong experience working with legacy / large-scale systems

 • Solid understanding of system architecture and performance optimization

 • Ability to work independently and take ownership

 • Experience dealing with technical debt and refactoring

 • Good spoken English (B2+)

 • Experience using AI tools (e.g., Copilot, ChatGPT) in development is a plus

➕ Nice to Have

 • Experience with on-premise enterprise systems

 • Background in system modernization or migration projects

 • Experience working in distributed/international teams