Rust Developer

About Balthazar Balthazar is the R&D intelligence platform for deep tech teams building complex technologies.

Balthazar provides a structured R&D environment where experiments, prototypes and decisions form one connected, traceable history. This creates the foundation on which AI can actually be useful - helping teams move with confidence, repeat what works, and scale without losing understanding.

We work with cutting-edge labs and engineering teams to turn experimental work into a structured, searchable source of truth that accelerates technology development.

Learn more: https://www.balthazar.app/

The role We’re looking for an autonomous Rust developer to own meaningful parts of:

Backend services

for our web application (performance + security + reliability) A

Runner application

that executes measurements on remote lab setups (desktop machines) and loads results back into the platform

This is a

longer-term contract

role in

hybrid mode

(a few days in the office, a few days WFH) in the Netherlands.

What you’ll do Build and evolve

high-quality Rust services

powering our platform and APIs ( REST + gRPC ) Develop and maintain the

Runner

that orchestrates measurements on remote lab desktops Design for

security

(secure-by-default patterns, tenant isolation mindset) Ship

high-performance data paths , with practical

PostgreSQL performance

fundamentals Write

unit + integration tests

so your work is fully auto-testable (we don’t “throw it over the wall” to QA) Collaborate via

peer reviews

and work closely with other engineers and product

What we’re looking for

Must-haves 3+ years

professional software development experience ( strong Rust required ) Self-starter

who unblocks themselves, drives work to completion, and communicates clearly Experience with

async Rust Solid understanding of

PostgreSQL performance basics Comfortable building and consuming

REST + gRPC

APIs Comfortable with

bash

and

docker Working knowledge of

software security practices Habit of writing

automated tests

(unit + integration) as part of delivery Eligible to work in the Netherlands Comfortable in a

fast-paced startup

environment with high ownership and fast feedback loops

Nice-to-haves Solid understanding of Python execution environments (venvs/conda, dependency management, packaging) and how Python code is executed Experience with desktop/edge execution agents, device orchestration, or lab/instrument integrations Production experience running containerized systems in

cloud and on-prem

environments Observability mindset: metrics/logging/tracing and practical debugging in production

Tech stack We deploy in

containers

in both

cloud and on-prem

environments. Our core stack includes

Rust

(Tokio, Axum, sqlx, Tonic),

PostgreSQL, REST + gRPC APIs , and

Python

integration via pyo3.

How we work Strong engineering culture with peer review and pragmatic standards High ownership, fast feedback loops, and close collaboration with product You own the quality of what you ship:

stability, performance, security, and testability

Interview process Technical interviews (Rust + DB + practical engineering) Interviews with founders

Practical details Contract type:

longer-term contract Location:

Amsterdam Zuid Start date: ASAP Competitive compensation

Send

CV / LinkedIn / GitHub

plus a short note on:

A Rust project you’re proud of (link if possible) A performance or security problem you solved (2–3 sentences)

Email:

joinus@balthazar.app