Muxify
muxify
Technical assessment, rebuilt

Hire engineers who ship with AI.

Replace coding puzzles with real build sessions. Watch how candidates think, decide, and direct the agent.

v24.14.1 ~/sessions/take-home-chat git:(main)
session active
Claude Code v2.1.132
Opus 4.7 (1M context) with xhigh effort · Claude Max
~/sessions/take-home-chat
~/sessions/take-home-chat (main)[Opus 4.7 (1M context)]8% used / 92% left
Found 2 settings issues · /doctor for details
+± 0▭ /remote-control▤ File explorer↳ Rich Input ^G
▢ ~/sessions/take-home-chatmain
Why now

The job changed. The interview didn't.

What every legacy platform still tests for, against what the work actually demands today.

hiring/skills.md
$git diff
+4/4
--- a/skills.md
+++ b/skills.md
@@ −1,4 +1,4 @@
Solve puzzles alone. No internet, no tools, no AI.
45 minutes of algorithmic recall under time pressure.
Measured on syntax fluency and trivia.
Predicts on-job performance? No.
Ship a feature on a real 40k-LOC repo.
Full session captured for review.
Measured on decisions, problem decomposition, agent control.
Predicts on-job performance? Yes.
1 file changed, 4 insertions(+), 4deletions(−)
For engineering leaders

How hiring works on Muxify.

From setup to a hiring decision in three steps. Your repo, your stack, the AI tools your team uses.

configure

Pick a repo. Pick a problem.

Connect your GitHub repo, set the time limit, and you're live in two minutes.

repositoryacme-co/checkout-api
stackTypeScriptPostgres+2
levelL3L4L5L6
time box60m
promptAdd idempotency keys to /charge
invite

Send a single magic link.

One link, zero setup. Candidates work in a cloud terminal with their AI tool of choice, exactly how they would on the job.

muxify.tech/s/a8f-92k1-7dcopy
expires in 7 days·single use
RKRiya K.opened · 2m ago
TMTheo M.submitted · yesterday
JLJamie L.invited · 3 days ago
review

Watch the session, not just the score.

See every prompt, edit, and decision in a full session replay. Read the final PR and hire with confidence.

replay · candidate-782100:42:18 / 01:00:00
14:02opened README.md
22:41prompt → Claude
33:08edit client.ts +24 −2
56:11ran tests · 9 / 9 passing
For candidates

What the candidate actually sees.

No webcam. No invigilator. No memorized tricks. Just a repo, a terminal, and the AI tools you already use.

before

Algorithm grinder

  • — Algorithm puzzles under a stopwatch
  • — No internet, no AI, none of your tools
  • — A pass/fail score that misses what matters
  • — The same question bank every platform asks
on muxify

Real build session

  • + Open the repo, ship like you do at work
  • + Use Claude Code, Codex, or OpenCode. Your choice
  • + 60 minutes async, on your own schedule
  • + Reviewed on the work, not a number
Session replay

Watch the work, not the résumé.

Every terminal command, file edit, and AI prompt is recorded. Scrub the timeline, comment inline, and share with your hiring panel.

Muxifysession activecandidate-7821 · take-home-chat
00:42:18Share replay
Files
  • src
  • App.tsx
  • components
  • MessageList.tsx
  • Composer.tsx
  • lib
  • package.json
  • README.md
src/components/MessageList.tsx
1import { useEffect, useState } from "react";
2import { fetchMessages } from "../lib/client";
3
4export function MessageList() {
5 const [items, setItems] = useState([]);
6 useEffect(() => {
7 fetchMessages().then(setItems);
8 }, []);
9 return <ul>{items.map(...)}</ul>;
~/sessions/take-home-chat git:(main)
claude-code
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▝▜█████▛▘
  ▘▘ ▝▝
Claude Code v2.1.132
Opus 4.7 · ~/sessions/take-home-chat
Wire MessageList to /api/messages with optimistic updates.
·Reading src/components/MessageList.tsx
Adding fetch + optimistic queue. Two edits.
·Edit src/components/MessageList.tsx +24 −2
Brewed for 4s
~/sessions/take-home-chat (main)[Opus 4.7]32% / 68%
2 edits · /history
+± 2▭ /remote-control▤ Files
⎇ main
Timeline00:00:00 — 01:00:00
Replay length00:42:18·Files changed7·Diff+148 −22·Agentclaude-code·Tests9 / 9 passing
The assessment library

Real problems, sourced from real products.

Every problem is sized so a senior engineer hand-coding for the full hour would not finish. The point is to see how someone directs an agent under realistic pressure.

build60m

Multi-tenant analytics dashboard

Wire a tenant-scoped /analytics page with four chart types, a date-range filter, the API routes, the SQL, and tenant-isolation tests into a 40k-line SaaS starter.

Next.jsPostgresdrizzle
integrate60m

Tool-calling for an existing chatbot

Extend a production chat app with three internal tools (search_users, create_ticket, fetch_user). Schema, agent loop, retries, safety guards, tests.

TypeScriptAnthropic SDK
debug45m

Regression across the checkout flow

A refactor broke checkout in a 50k-line monorepo. Trace the bug across the frontend hook, the API client, the server endpoint, and the DB query. Ship the fix plus regression tests.

ReactNodePostgres
vs. legacy assessment platforms

The same problem, solved differently.

LeetCode tests for a world without AI. Muxify tests for the one your team actually works in.

What gets measured
Shipping working code on a real repo
Algorithm puzzle pass/fail
Tools the candidate uses
Real terminal with their AI tool of choice
Pen, paper, no internet
Session length
30–90 minutes
45 minutes of stress
What you review
Full session replay + final PR
A score and a leaderboard
AI usage
Encouraged. The whole point.
Strictly forbidden
Signal for senior ICs
Direct. They did the job.
Indirect. A proxy for tenacity.
A note from the founder

We hire engineers who use AI every day. The interview never caught up.

Every engineer on a serious team now ships with Claude Code or Codex daily. The "no internet, no AI, solve this puzzle alone" interview measures a job no one actually does anymore.

When the test does not match the job, the signal you hire on is the wrong signal. Strong builders look mediocre on algorithm puzzles. Mediocre puzzle-solvers look strong. Hires miss either way, and the team pays for it for two years.

Muxify is the assessment for the job your team actually hires for. Real repo, real AI, real session, real signal. We built it because we wanted it for our own loops first.

Tod·founder
Hiring stack

Built for the tools your team already uses.

GitHub
Slack
Linear
Greenhouse
Notion
Loom
Pricing

Flat pricing. AI compute included.

One tier covers most hiring teams. Custom plans for higher volume or specific procurement requirements.

Enterprise

Custom
  • Custom candidate assessments per month
  • Bring your own AI provider keys
  • SSO and audit logs
  • ATS and third-party integrations
  • Dedicated point of contact
Contact Sales
Questions

The questions engineering leaders ask first.

Is using AI during the session allowed?

Yes, that's the whole point. Muxify shows you how candidates work with AI, not whether they can avoid it.

What happens to the candidate's code?

It stays in the candidate's session repo. You get the final state, the diff, and the full replay. Export to a private GitHub repo your team owns, or discard after a retention window you set.

What signal do you actually get from a session?

You see how a candidate reasons through ambiguity, where they get stuck, how they direct the agent, and what they choose not to do. The journey is much harder to fake than a finished commit.

What languages and stacks are supported?

TypeScript, Python, Go, Rust, Ruby, Java, and their surrounding tooling. The cloud terminal is a full Linux environment, so anything that runs on Muxify.

How long does a typical assessment take to set up?

Two minutes. Connect a GitHub repo, write a one-paragraph prompt, and set a time limit. Or start from our library of pre-built problems.

Will Muxify fit into our hiring stack?

We're constantly rolling out integrations. If there's an integration you want, lets talk.

request
Get started

Watch a real session before you commit.

Tell us about your team. We will send a short walkthrough and book time if you want it.

  • 30-minute live demo with the founders
  • Two sample sessions tailored to your stack
  • No pitch deck, no sales floor

We reply within one business day.