developer English-speaking jobs in Leidschendam

Senior Quantitative Researcher develops systematic, short-horizon trading signals from idea generation to live implementation using high-frequency market data. Requires experience in electronic trading, signal development, and robust backtesting.

Junior Account Manager to promote and sell the product portfolio in the Benelux/UK region. Develop customer relationships, identify new business, and achieve sales targets. Requires 2-3 years of commercial experience.

Provide first-line ICT support via phone and chat, registering, analyzing, and resolving incidents. Requires MBO-4 ICT diploma, Windows 11 knowledge, and 6 months of first-line IT support experience.

Working in a small friendly team as a Production Operative (Temporary), 40 hours p/week until 22nd December 2026. Position to be reviewed end of year depending on key account orders.

Sales Development Representative focusing on finding new customers and creating business opportunities. Responsibilities include contacting potential customers, identifying new business, and following up on leads. Requires sales experience, strong communication, and good command of German and English.

Experienced Mechanical or Electrical Engineer to lead R&D projects from concept to implementation. Own the R&D lab, improve product quality, and develop technical solutions. Requires 5+ years of relevant experience and SolidWorks/AutoCAD skills.

Support the Den Manager in running two daily supervised childcare sessions for babies to 8-year-olds. Help develop and deliver family activity programs. Requires childcare experience and Level 2 accredited qualification.

Business Development Rep to build the top of the revenue funnel by prospecting and communicating with potential customers. Requires fluency in English and a Nordic language, plus a drive to launch a B2B tech sales career.

Cell Therapy Manufacturing Technician role in a GMP cleanroom. Responsibilities include executing aseptic manufacturing, cell culture processes, and maintaining documentation. Requires 2+ years in GMP manufacturing, preferably in cell therapy.

Experienced Industrial Insulators needed for major projects in refineries and chemical plants. Responsibilities include installing thermal/acoustic insulation and fabricating metal cladding. A valid VCA or SCC certificate is mandatory.

Determine cost prices for multidisciplinary energy projects by analyzing requirements and technical documentation. Coordinate with various departments to ensure accurate cost accounting on projects up to €100M.

Online Data Analyst reviews and evaluates map, location, business, and search information using Dutch and English knowledge. This remote, flexible role requires in-depth knowledge of the Netherlands and regular participation when tasks are available.

Work Preparer for aerospace and space applications. Prepare and coordinate production and integration activities, managing planning, documentation, and materials in a high-tech environment. Requires HBO+ level and experience with MRP systems.

Technical Support Specialist ensures exceptional service by assisting technicians, diagnosing complex vehicle issues, and bridging communication between workshops, customers, and the manufacturer. Requires an automotive engineering background and 2+ years of technical support experience.

Junior Project Manager in digital rights leads projects within established frameworks, balancing strategy and execution. The role involves liaising with image makers and organizations while focusing on concrete completion, schedule, and budget. Strong communication in Dutch and English is required.

Lighthouse Reports seeks a full-time Social Media Manager to build social presence for public interest investigative work. Responsibilities include content creation, strategy execution, and managing creator partnerships. Requires 3-5 years in video editing and social media management.

Smartphone Repair Technician needed to diagnose and repair mobile devices. Responsibilities include hardware/software fixes, customer advising, and stock management. Fluent Dutch and good English are required.

Full-time Store Colleague needed for JD Sports. Responsibilities include greeting customers, maintaining displays, replenishing stock, and supporting daily store tasks in a fast-paced retail environment. Requires enthusiasm and flexibility.

Sales Assistant role involving processing goods, visual merchandising, and cash register work. Requires customer service orientation, a hands-on mentality, and a passion for fashion.

Customer Success Consultant needed to drive client growth and satisfaction. Oversee account health, conduct QBRs, and engage senior stakeholders. Requires 3+ years' experience and fluency in Dutch and English.