Unrust
Free unassisted coding skills diagnostic for developers
A 14-minute, timed assessment measuring six core coding skills—recall, debugging, tracing, and more—without AI assistance or autocomplete.
The pitch
Unrust is a free diagnostic that measures six core coding skills in 14 minutes without AI assistance: recall, debugging, finding faults, tracing, idiom and quality, and AI-slop detection. It produces a per-skill profile showing where abilities are Sharp, Holding, Rusty or Offloaded. You can retake the test over time to track skill decay trends. With a free account, you get one daily adaptive practice set and a game layer that counts effort through XP and practice days. A subscription adds unlimited practice, the full drill library, per-skill mastery ladders, interview pre-flight planning, and language-specific tracking across JavaScript, TypeScript and Python.
Under the hood
- 14-minute AI-off diagnostic measuring six coding skills
- Per-skill profile with bands from Sharp to Offloaded
- Trace replay showing variable changes line by line
- Adaptive daily practice with spaced repetition
- Mastery ladder tracking skill levels Cold to Sharp
- XP and practice day gamification layer
- Full drill library browsable by skill, difficulty and language
- Interview pre-flight seven-day plan
- Skill decay trend over time with dated retakes
- Per-language tracking for JavaScript, TypeScript and Python
Pricing
Pricing model: Freemium
Free: 14-minute diagnostic, one daily practice set with free account, daily puzzle, share cards. Monthly flex: $4.99 first 30 days, then $10.99 per 30 days. Annual rebuild: $84 for 365 days (about $7 per month, save 33%). Paid in USDT, USDC or DAI on Ethereum; no auto-renewal.
Quick answers
Is the diagnostic really unassisted?
Yes. The diagnostic is designed for an AI-off condition. It is a mirror to see how your unassisted performance looks today, not a gate or hiring grade.
What do the score bands mean?
The bands group performance into provisional product categories: Sharp, Holding, Rusty or Offloaded. These are not validated population percentiles or hiring grades. Read comparable retakes with their uncertainty rather than treating a single number as a verdict.
Does practice change my diagnostic score?
No. Practice and the diagnostic are deliberately separated. Practice moves your per-skill mastery; only the diagnostic moves the longitudinal trend.
How do languages work?
You pick a default language for your account—JavaScript, TypeScript or Python. It filters the whole experience and metrics are tracked per language. Switching to a new language starts fresh; switching back restores earlier progress untouched.
Do I have to practise every day?
No. Each week, two days off are free rest days, and a third uses a banked streak freeze. Five forge days out of seven meets the week's goal.
Unrust has a free listing. The owner can unlock the full profile with a paid launch for $5:
- Founder story (locked)
- Milestones (locked)
- Demo video (locked)
- Dofollow website link (locked)
