As an Embedded Engineer at Alten Spain, you are stepping into a dynamic and highly impactful consulting role. Alten is a global leader in engineering and technology consulting, meaning you will not just be building software for a single internal product. Instead, you will be deployed on critical projects for top-tier clients across industries such as automotive, aerospace, telecommunications, and industrial automation. Your work directly drives the innovation of physical products, bridging the crucial gap between complex hardware and intelligent software.

This position is critical because Alten Spain relies on its engineers to be both technical experts and trusted advisors to its clients. You will be responsible for designing, developing, and optimizing firmware and embedded systems that must operate under strict performance, memory, and safety constraints. Whether you are programming microcontrollers for a next-generation electric vehicle or optimizing the memory allocation of an IoT sensor, your code will live at the edge of technological advancement.

Expect a role that requires high adaptability and strong foundational engineering skills. Because you will often integrate directly with external client teams, you must be comfortable navigating new environments, understanding diverse tech stacks, and delivering robust solutions under tight deadlines. It is an exciting, fast-paced environment that offers unparalleled exposure to different industries and cutting-edge hardware.

The questions below represent the types of technical and behavioral inquiries candidates frequently face at Alten Spain. While exact questions depend on the client project, these patterns are highly consistent across interviews. Focus on understanding the underlying concepts rather than memorizing answers.

C/C++ and Memory Management

These questions test your fundamental grasp of the languages most critical to embedded development.

• Explain the difference between the heap and the stack. Where are local variables stored?
• What is the purpose of the volatile keyword, and give an example of when you must use it in embedded systems.

Preparing for an interview at Alten Spain requires a dual focus: mastering core technical fundamentals and demonstrating your readiness to operate as a consultant. Your interviewers will look for a blend of deep technical know-how and the soft skills necessary to thrive in client-facing environments.

Here are the key evaluation criteria you must prepare for:

• Technical Fluency – You must demonstrate a strong command of C and C++ programming, memory management, and microcontroller architecture. Interviewers will test your ability to write efficient, hardware-aware code.
• Problem-Solving Ability – You will be evaluated on your logical thinking and how you approach debugging complex hardware-software integration issues. Interviewers want to see a structured, analytical mindset.
• Consulting Fit and Adaptability – Because you will be working on specific client projects, Alten evaluates your flexibility, communication skills, and ability to quickly integrate into new teams and workflows.
• Domain Alignment – Interviewers will assess how well your specific past experiences match the immediate needs of the client project you are being considered for.

The interview process for an Embedded Engineer at Alten Spain is generally streamlined, typically taking between two and three weeks from the initial contact to the final decision. The process is designed to evaluate both your technical baseline and your fit for specific client assignments. You will start with an introductory phone screen with HR, which focuses on your background, motivation, and availability.

Following the HR screen, you will have a more detailed interview with a Business Manager (BM) or Competence Manager. This stage dives deeper into your resume, often requiring you to fill out a "competence file" that maps your skills to potential projects. The technical evaluation usually follows, which may involve a technical discussion, a live test on C/C++ programming, and logical reasoning questions.

Because Alten Spain operates as a consultancy, the final stage is uniquely structured: you will almost always have a technical and cultural interview directly with the client you will be working for. This final step is crucial, as the client must approve you for the project before an offer is extended.

This visual timeline outlines the typical progression of the Alten Spain interview process, moving from internal screening to external client validation. Use this to pace your preparation; focus heavily on core technical concepts for the internal rounds, and pivot to project-specific domain knowledge before the final client interview. Note that the exact order of the technical test and the Business Manager interview can occasionally swap depending on the urgency of the role.

To succeed, you need to understand exactly what the technical and managerial teams at Alten Spain are looking for. The technical rounds are described by candidates as being of average difficulty, focusing heavily on fundamental embedded concepts rather than obscure algorithms.

C and C++ Fundamentals

At the heart of any embedded role is a deep understanding of C and C++. Interviewers will not just ask for syntax; they want to know how your code behaves at the memory level. You must be prepared to discuss how the compiler handles your code and how to optimize for constrained environments.

Be ready to go over:

• Memory Allocation – Deep dive into stack vs. heap, memory leaks, and dynamic vs. static allocation.
• The static and volatile keywords – You must know exactly how, when, and why to use these in an embedded context.
• Object-Oriented Programming (OOP) – If the project uses C++, expect questions on inheritance, polymorphism, and encapsulation applied to embedded systems.
• Advanced concepts (less common) – Function pointers, bit-field manipulation, and inline assembly.

Example questions or scenarios:

• "Explain the different uses of the static keyword in C."
• "How would you implement polymorphism in a C++ embedded application without using dynamic memory?"
• "Walk me through how you would debug a memory leak in a bare-metal environment."

Microcontrollers and Hardware Interaction

You are expected to know how software interacts with physical hardware. Alten Spain looks for engineers who are comfortable reading datasheets and manipulating hardware directly.

Be ready to go over:

• Registers and Bitwise Operations – Setting, clearing, and toggling specific bits in a hardware register.
• Interrupts vs. Polling – Understanding Interrupt Service Routines (ISRs), interrupt latency, and when to use each approach.
• Peripherals and Protocols – Familiarity with standard communication interfaces like SPI, I2C, UART, and CAN bus.
• Advanced concepts (less common) – Direct Memory Access (DMA) configuration and real-time clock (RTC) management.

Example questions or scenarios:

• "Write a macro in C to set the 4th bit of a 32-bit register."
• "What are the best practices for writing an Interrupt Service Routine?"
• "Explain the difference between SPI and I2C, and tell me when you would choose one over the other."

Logical Thinking and System Architecture

Beyond syntax and hardware, you will be evaluated on your overall engineering logic. This involves how you structure a system, manage state, and troubleshoot complex issues.

Be ready to go over:

• State Machines – Designing finite state machines (FSM) for device control.
• Real-Time Operating Systems (RTOS) – Understanding tasks, semaphores, mutexes, and scheduling (if applicable to the project).
• Debugging Methodology – How you isolate faults when you don't know if the issue is in the hardware or the software.

Example questions or scenarios:

• "How do you prevent priority inversion in an RTOS?"
• "Describe your step-by-step process for debugging a device that randomly resets after a few hours of operation."

Consulting and Client Fit

Because you will be representing Alten Spain on client sites, your professionalism, communication, and adaptability are heavily scrutinized by the Business Manager.

Be ready to go over:

• Project Alignment – How your past experience translates to the specific client's industry (e.g., automotive or aerospace).
• Stakeholder Management – How you communicate technical blockers to non-technical managers.
• Adaptability – Your willingness to learn new proprietary tools or frameworks used by the client.

Example questions or scenarios:

• "Tell me about a time you had to quickly learn a new microcontroller architecture for a project."
• "How do you handle a situation where the client changes the system requirements halfway through the development cycle?"

As an Embedded Engineer at Alten Spain, your day-to-day work will be heavily dictated by the specific client project you are assigned to. Generally, you will be responsible for the full lifecycle of embedded software development. This includes gathering requirements, architecting firmware solutions, writing efficient C/C++ code, and rigorously testing your software on target hardware. You will frequently interact with hardware engineers to validate schematics and ensure seamless hardware-software integration.

You will spend a significant portion of your time debugging complex systems using oscilloscopes, logic analyzers, and JTAG debuggers. Because you are a consultant, you will also be responsible for maintaining clear documentation and providing regular progress updates to both your Alten Business Manager and the client's technical leads.

Collaboration is a massive part of this role. You will often integrate into Agile teams directly at the client's location or work in a hybrid model from an Alten office. You will participate in code reviews, sprint planning, and architecture discussions, acting as a proactive problem-solver who drives the project forward.

To be a competitive candidate for the Embedded Engineer role at Alten Spain, you need a solid foundation in low-level programming and hardware interaction. The ideal candidate blends technical rigor with the flexibility required in consulting.

• Must-have skills – Exceptional proficiency in C and C++. Hands-on experience programming microcontrollers (e.g., ARM Cortex-M, STM32, PIC). Deep understanding of memory management, pointers, and bitwise operations. Strong logical thinking and debugging skills.
• Experience level – Typically requires a degree in Electronics, Telecommunications, Computer Engineering, or a related field. Candidates usually have 2 to 5+ years of experience, though Alten also hires junior engineers for specific apprenticeship or entry-level project roles.
• Soft skills – Excellent communication skills, a high degree of adaptability, and a strong sense of ownership. You must be comfortable presenting your ideas to external stakeholders.
• Nice-to-have skills – Experience with RTOS (FreeRTOS, Zephyr). Knowledge of automotive standards (AUTOSAR, MISRA C) or communication protocols like CAN, LIN, and Ethernet. Experience with version control (Git) and CI/CD pipelines in embedded environments.