Senior Python Engineer - Healthtech

Vesynta

Vesynta is an investor-backed precision medicine company based within the London Cancer Hub. We are building clinical decision support software that personalises dosing of critical therapies at the point of care which provide clinicians with access to data-backed pharmacology models; resulting in fewer toxic side effects, and significantly improved treatment efficacy. We exist to support patients (children, but also women and those with diverse ethnic heritages) who have been traditionally under-represented and poorly served by traditional, coarse dosing methodologies. Our team is fast-paced, results-oriented, and mission-driven.

The Job

As a Senior Python Engineer, you will develop the core computational modules for our pharmacometrics engine. You will be a dedicated pure Python expert responsible for translating complex scientific models into production-ready software to personalise dosing for children undergoing cancer care.

Key Responsibilities:

• High-Performance Python: Write custom, highly efficient modules using vectorised operations (numpy, pandas, attrs) to calculate critical clinical metrics.
• System Design & Integration: Engage directly with internal software design processes, actively contributing to and following Mermaid.js UML and flow charts for architecture and pipelines.
• Math to Code: Read and translate advanced mathematical equations into robust code, backed by strict unit testing against hand-calculated ‘golden’ datasets.
• Cross-Language APIs: Own the integration of Python models with an industry-standard R backend (via rpy2), exposing them securely through FastAPI and gRPC.

The Products

Our web, mobile and Electronic Health Record-integrated applications offer best-in-class actionable precision dosing insights to healthcare professionals, supporting the end-to-end process of Therapeutic Drug Monitoring and Model Informed Precision Dosing. With these, the primary users (hospital-based clinicians, pharmacists and nurses) are able to provide patients with enhanced and personalised care across several therapeutic areas including antibiotics, chemotherapeutics and immunosuppressants.

Recruitment Process

We conduct our entire recruitment process online to ensure fairness and accessibility for all candidates. Each stage is distinct and focuses on different attributes. The process is intended to be efficient (typically taking around 2 weeks to complete) - some stages are particularly quick to schedule and progress through. Here’s a breakdown:

1. Application Screening: A review of your CV by our team to assess your experience and high-level fit against the key role requirements.
2. Initial Screening Call: A brief introductory chat via Google Meet to discuss your background, expectations, and mutual alignment with the role.
3. Technical Challenge: A take-home Python coding assignment sent via email to evaluate your technical approach and problem-solving skills at your own pace.
4. Final Interview: A two-part session consisting of an in-depth technical evaluation (discussing hard skills and logic) and a conversational culture-fit exploration.
5. Selection & Offer: We make a final decision based on a comprehensive review of all stages and extend a formal offer to join the team.

Recruiters

Vesynta is managing this recruitment process directly and we are only accepting applications from candidates themselves. We do not accept unsolicited CVs or candidate profiles from recruitment agencies. Any unsolicited submissions will not be deemed an introduction, will not form the basis of any contractual agreement (implied or otherwise), and Vesynta will not be bound by any agency terms and conditions. We reserve the right to contact and hire any candidate whose details have been shared with us unsolicited, without any financial obligation or finder’s fee to the submitting agency.

Requirements

Essential:

• 5+ years of backend software engineering focusing on computationally heavy, pure Python environments.
• Expert-level Python: Deep knowledge of the Python Data Model, strict typing protocols (mypy), and memory lifecycle management (GC, profiling via tracemalloc).
• Scientific Libraries: High proficiency in NumPy, SciPy, and Pandas for vectorization, data structures, and optimized mathematical execution.
• Math Translation & Unit Testing: Proven ability to translate advanced mathematical equations and scientific pseudocode into performant, rigorously unit-tested algorithms directly from logic specifications.
• System Documentation: High comfort level reading from, building, and contributing directly to Mermaid.js UML and flow charts to govern architectural decisions.

Desirable:

• Experience designing, maintaining, or scaling RESTful endpoints using FastAPI and configuring gRPC interfaces for high-performance communication.
• Familiarity with R and prior experience employing rpy2 (or analogous FFI bridges) to invoke non-Python scientific kernels from a Python ecosystem.
• Prior work in life-sciences, pharmacometrics, bioinformatics, quantitative finance, or domains featuring rigorous numerical and mathematically validated software pipelines.

If you’re passionate about our mission and confident you can make a significant contribution, we encourage you to apply (even if you don’t perfectly match every requirement). While this posting is for a Senior Python Engineer, we may, on occasion, identify exceptional candidates who are a strong fit for our team but whose experience aligns more closely with a different role. In such cases, we may discuss alternative opportunities within Vesynta.

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

Benefits

• Impact Opportunity to create, and deliver real-world impact for children who are critically ill.
• Flexibility Hybrid and flexible working policy, where team well-being and quality of work are prioritised.
• Growth: Opportunities for professional development, mentorship, open-source contributions, and shaping our technical direction.
• Compensation Competitive salary, 30 days annual leave, subsidised private health insurance, salary sacrifice schemes (home tech., bicycles, electric cars), stock options and more.
• Support and Culture Independent HR, TOIL provision, Employee Assistance Programme (ensuring personal and professional well-being), NEST workplace pension, structured parental leave packages, family-friendly working arrangements and inclusive company socials.
• Visa Sponsorship Vesynta is a UK approved VISA sponsor.