indie-hacker
Tony Dinh
TypingMind
A better chat UI for the OpenAI API turned into a $1M+ ARR one-time-purchase SaaS run solo.
Revenue
$1M+ ARR
Time to build
2 weeks (v1)
Launched
Mar 2023
Location
Ho Chi Minh City
The story
Tony was frustrated by ChatGPT's throttling and prompt loss, so he built a client that talks to the raw OpenAI API and stores everything locally. He priced it as a one-time license ($39-$79) rather than subscription, ran it fully client-side on Cloudflare Pages, and let word-of-mouth on X do the marketing. It hit six figures ARR in the first quarter.
Stack
React
Cloudflare
OpenAI API
LemonSqueezy
Reported metrics
ARR
$1M+
Team
Solo
Pricing
One-time
The full build breakdown
Pro insight
Pro only
Unlock the full breakdown
Timeline, costs, revenue curve, marketing tactics with sources, growth channels, team, and lessons — all publicly-sourced.
Month-by-month timeline
- Feb 2023Prototypes ChatGPT alternative on top of raw OpenAI API
- Mar 2023Launches on X + Product Hunt$5k first week
- May 2023Hits $10k MRR equivalent from one-time sales
- Sep 2023Crosses $500k in cumulative revenue$500k
- 2024Passes $1M ARR run-rate$1M ARR
Cost breakdown
| Hosting (Cloudflare Pages) | ~$0/mo | Static + Workers free tier |
| LemonSqueezy fees | 5% + 50¢/txn | Merchant of record |
| Domain | $12/yr |
Marketing tactics
- X / TwitterBuild-in-public revenue milestones with screenshots
- Product HuntLaunch with lifetime-license teaser
- SEORanks for 'ChatGPT alternative' + 'OpenAI API client'
Launch plan
- Ship a local-first UI in one weekend. No backend, no accounts — user's own API key
- Price it as a one-time license. Cuts churn and support to near-zero
- Post the revenue publicly. Each milestone doubles as an ad
Growth channels
Twitter/X organic
Primary
SEO ('ChatGPT alternative')
Compounding
Word of mouth
Loved by power users
Team composition
- 1 · Founder
Tools deep-dive
Cloudflare Pages · Hosting
Free static hosting + Workers for the tiny backend
LemonSqueezy · Payments
Merchant of record — solves VAT globally
OpenAI API · Model
Users bring their own key — no per-user token cost
Lessons
- Ship local-first — user's API key means zero infra cost
- One-time pricing kills churn
Pitfalls
- Support load spikes on every OpenAI outage
- Copycats appeared within weeks
Current status
Solo, profitable, actively shipping features and multi-provider support.
Publications & press mentions
Live searches across the biggest tech publications, podcasts and communities covering Tony Dinh.
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