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Jumbl

Find jobs through referrals from people already inside the companies.

sunset Former Co-founder & CTO Former · CTO
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Problem

Applying for a job through the front door is mostly a black box. You send applications into a portal and wait: no signal, no advocate, no idea if a human ever saw it. The thing that actually moves the needle is a referral from someone already inside the company, and that’s the hardest thing to get if you don’t already know someone there.

Why I co-founded it

Referrals work, but access to them is unevenly distributed. It usually comes down to who you already know. We started Jumbl to open that path up: give candidates a way to reach people inside the companies they’re targeting, and give those insiders a simple way to refer.

The product idea

Connect the two sides of a referral (candidates looking for a way in, and referrers already inside companies who can vouch for them) alongside the job discovery that brings them together. A promising candidate and a willing insider could actually find each other in one place.

My role

I co-founded Jumbl and led it as CTO. I worked across the whole thing (product direction and the engineering behind it), from how the core experience should feel to the systems that ran it.

Product decisions

  • Referral as the core mechanic, not an add-on bolted onto a job board.
  • Distinct experiences for the candidate and referrer sides, so each only dealt with what was relevant to them.
  • Keep the path from “interesting candidate” to “introduction made” as short as possible.

Engineering decisions

  • React Native so candidates and referrers got a real mobile app from a single codebase.
  • Node.js + MongoDB for the backend, data, and the logic connecting candidates to referrers.
  • The data model centred on the referral itself: the link between a candidate, an opening, and the insider willing to vouch.

What shipped

A working referral-based job product: candidates could discover opportunities and reach referrers inside companies, and referrers had a clean way to refer: the core loop of finding a job through someone already on the inside.

Current state

A venture I co-founded, built, and led as CTO. A real referral-based hiring product taken from idea to a working two-sided platform.

What I learned

Two-sided products are hard in a specific way: each side is only valuable once the other side shows up, so the cold-start matters more than the feature list. The most useful lessons from Jumbl were about scoping a referral experience down to the part that genuinely creates value.

Jumbl, from profile to offer in days. Build a profile, apply, hear backJumbl: built for the way startups actually hire