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KastleKastle

Founder Intern (now and Summer 2026)

Founder Intern works directly with founders on all aspects of an AI consumer lending startup, shipping products, handling operations from support to engineering, and operating autonomously in a high-intensity environment. Requires being very technical and relentlessly resourceful.

About the job

Responsibilities

  • Ship real products.
  • Touch every part of the business: customer support, growth, operations, engineering, and sales.
  • Work directly with founders and unblock them.
  • Handle the hardest, most boring, least glamorous tasks — without flinching.
  • Operate with extreme autonomy in an unstructured, high-paced environment.
  • Take vague prompts like “build something that helps the company grow” and turn them into working systems — on your own, or by rallying others to help.

Ideal Candidate

  • Relentlessly resourceful.
  • Learns fast, moves faster.
  • Cares about quality.
  • Very Technical.
  • Can start next week.

Skills

Engineering, Customer Support, Growth, Operations, Sales

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