2,918 Founding Engineer jobs
Founding engineer roles building the first product at early-stage startups.
Principal Flight Software Engineer
Principal Flight Software Engineer at K2 Space in Los Angeles designs and implements real-time, fault-tolerant control software for high-power satellites using Rust, C++, and Python, with responsibilities spanning architecture, subsystem integration, and on-orbit operations.
Senior Software Engineer
Senior Software Engineer at an early-stage startup building an AI-powered tax preparation platform for accounting firms. Full-stack ownership of product architecture, working across a React/Remix frontend, TypeScript/Node.js backend with Postgres and Weaviate, and AWS/Kubernetes/Terraform infrastructure.
Senior Software Engineer
Senior full-stack engineer at H2 Analytics building EASE, a training-exercise simulation platform for military, intelligence, and emergency-response clients. Day to day: designing and shipping features in TypeScript/Vue with MongoDB/PostgreSQL, deploying to AWS and air-gapped on-premises, and mentoring developers.
Senior Flight Software Engineer
Designs, develops, and tests real-time embedded flight software for missile systems at an early-stage defense company, collaborating with GNC, systems, and hardware teams. Core work is C/C++ on real-time operating systems, with simulation, hardware-in-the-loop, and flight testing in safety-critical environments.
Member of Technical Staff, AI Engineering for Biosecurity
Research scientist/engineer on an AI lab's biosecurity team: fine-tune and post-train multimodal genome language models, design evaluation frameworks, run interpretability/ablation experiments, and translate capabilities into deployable biodefense tools. Core stack: Python, PyTorch/JAX, large-scale distributed ML, genomics.
Staff Software Engineer (Infrastructure)
Staff engineer on Félix's SRE team leading developers who build the internal developer platform: Go services, internal tools, and open-source integrations running on Kubernetes and GCP, keeping the fintech's infrastructure reliable, secure, and developer-friendly as it scales.
Member of Technical Staff - Research
Researcher building agent-simulation environments and reinforcement-learning systems to train and evaluate frontier AI models for safe, human-aligned general intelligence.
Member of Technical Staff - Engineering
Broad full-stack engineering role at Patronus AI building simulation environments, agent-training infrastructure, internal developer platforms, and ML model serving for AI evaluation research. A hands-on generalist working across frontend, backend, infra, and LLM/agent tooling, on-site in San Francisco 5 days a week.
Senior Software Engineer - Security
Senior Security Engineer owning Loancrate's security posture end to end: threat modeling, AWS hardening (IAM, secrets, GuardDuty), CI/CD security tooling, SOC 2 Type II compliance, identity/access, and incident response. Stack is AWS via Terraform/Pulumi, Docker on ECS, and a TypeScript/Node/React/GraphQL monorepo.
Engineering Manager, Data Streaming
Leads Horizon3's Data Streaming sub-team (growing to 6–7 engineers) that collects, normalizes, and routes NodeZero pentest telemetry. Owns SLOs, data contracts, and pipeline scalability for streaming ingestion built in Go/Python with Kafka/Kinesis, PostgreSQL, and Kubernetes on AWS.
Member of Technical Staff, Product Security
Hands-on product security engineer who runs offensive testing (penetration testing of web apps, APIs, admin interfaces, agentic and code-generating AI systems) across Higgsfield AI's generative video platform, drives vulnerabilities to root-cause fixes with engineers, and builds automated security controls and standards. Stack touches Python/JS/TS/Go, cloud, and containers.
Payload Systems Engineer (I)
Early-career payload engineer at Lodestar (Los Angeles) who owns the day-to-day design, build, integration, and test of the CORONA payload engineering model for a SpaceWERX/USSF program — spanning optics, avionics, edge compute, and multimodal sensing (optical, LiDAR, radar) through design reviews and environmental qualification.
Senior/Staff Systems Engineer
Senior/Staff Systems Engineer who defines, integrates, and validates SirenOpt's plasma-based sensing platform for advanced manufacturing, on-site in San Leandro, CA. Day to day is cross-disciplinary system architecture, hands-on experimentation and data analysis (Python, MATLAB, C, LabVIEW), root-cause investigation, and shaping the company's technical documentation practices.
Senior Software Engineer
Senior backend engineer at an early-stage FinTech startup in Latvia building a green-field payments and card acquiring platform. You design and own backend services from problem to production, make architectural decisions, and work with Kubernetes and modern DevOps in a small autonomous team (hybrid, remote possible).
Model-Based Systems Engineer
Owns and builds the company's SysML 'ground truth' system model for Anura — capturing services, APIs, data flows, deployments, and hardware/network interfaces — and maps architecture to government reference frameworks while tracing requirements to verification. Needs 5+ years systems engineering, 3+ hands-on MBSE, and US citizenship.
Software Engineer
Software engineer at an early-stage AI startup building an agent layer for commercial insurance, shipping end-to-end across frontend, backend and infrastructure. Combines forward-deployed work for broker customers with core platform development; language-agnostic, in-office in London five days a week.
Software Engineer
Builds and runs browser automation (mostly Playwright/Puppeteer) that scrapes hotel rates and completes bookings on hotel websites, plus the data pipelines and white-label partner API behind them. Primarily Python/TypeScript with some Go services; no separate platform team, so you own your work in production.
Software Engineer: Infrastructure
Designs and maintains secure, HIPAA-compliant cloud infrastructure for a healthcare benefits platform, using Terraform and PostgreSQL to ensure reliability and performance.
IT Systems Engineer
Own Thatch's IT and identity infrastructure in a Mac-first environment: endpoint compliance (MDM/EDR/DLP via Okta, Iru, Rippling), conditional and privileged access workflows, and the full employee onboarding/offboarding lifecycle, while building automation and self-serve knowledge base tooling.