Douglas Li

Hey Product Hunt 👋 I’m Doug - I was OpenAI’s first hire in London but left to co-found Lightfern. The problem: AI-driven communication isn’t authentic. You want to communicate clearly and thoughtfully. But wording your thoughts is time-consuming. Lightfern is the telepathic AI writing tool. We started with a simple idea: Cursor, but for email. Today, we’re rolling out public availability for...

Congrats @dbul and team on the launch! I've seen firsthand how easy Ting was to work with, from the invitee site -- I had to reschedule a meeting with Dan and Ting instantly understood that, suggested alternative timeslots, and sent me a new invite after we confirmed. Really excited to see where this goes! (And looking forward to that catch up Dan ^^)

I do question AI all the time; outputs are often very convincing, but also sycophantic. It's hard to get an unbiased opinion from AI regarding something that I'm doing. I love the physical grounding of what you do in your life -- that's amazing! Do you do anything to "digital detox", or do you have established habits to make sure you stick with those activities? I'm finding exercise and...

Super cool! Just installed, gonna check this out :). Any backstory on the name though? I love eating tonkotsu ramen but really curious why you decided to name your company this. 豚骨ラーメンがおいしいですね🍜

I’ve found that with every new model version, I need to re-review outputs to make sure quality hasn’t shifted. We use a synthetic data pipeline, but even small changes in how a model writes can subtly change the output distribution. A lot of this feels like prompt overfitting -- similar to classic ML overfitting, but where prompts are implicitly tuned to a specific model version and don’t...

I'm going to go super deep. Check my profile but I hope you'll find me qualified to speak as someone on the "scientist" curve above. I also was at NeurIPS 2025 and there are some trends that are hitting a wall. This gap is real. I'm seeing stratospheric pre-seed raises based on teams alone and many investors are about to lose a ton of money. When I think of AGI, I think of something that can...

I actually think customer relationships and authenticity matter more than ever! It's really obvious when someone didn't really care these days because of the heavy use of AI writing. So when I get something personal or hand crafted I feel respected. We're building something around this actually - I think people would appreciate high quality help & writing advice, instead of AI doing all of the...

Definitely Sonnet 4.5, with occasional Opus 4.5 mixed in when it can't handle the task. It's pretty crazy how quickly it's improving too. Still significant hallucinations, but a good AGENTS.md can dramatically reduce the ones that repeatedly pop up (e.g. assuming a certain testing framework, etc.)

We're planning about 4 weeks in advance, and have already reached out to supporters that we know. We also set up a slack group for supporters to coordinate all "pre-launch" activities and necessary updates for folks following us. What are you planning to share in the informational newsletter to keep it interesting for subscribers? I'm also curious re the list of supporters - were you planning...

We're a team of 6, and honestly, we don't 😅. Everybody has their own company card and just expenses whatever AI services they're using. Everyone's spending is within reason, so we've not had to change this. This might not scale but it's fine for now.

Super interesting in how this is coordinated. I wonder if they feature highlight simply because people already know Cursor and what it does. If I didn't know about cursor before, "our first coding model and new interface for agents" doesn't really tell me much about the product. But totally agree re relatability -- it's clear they understand their audience is already familiar with their...

Buzzwordy messaging. I see this with a lot of B2B websites; it's full of slick animations but even after rereading their homepage multiple times I have no idea what they do. Public, well known companies do this and it really bothers me. Real snippets from well known companies Brand name commented out, but you can Google 😉 Ops teams build what they need while IT gets oversight. Enterprises trust...

Give us a try! Lightfern helps sales and marketing teams write high-quality emails at high volume, without sounding automated. It adapts to your voice and context, and works directly in Gmail. Sign up here: https://lightfern.com/sign-up?code=5UQNTTGR

Thanks for sharing :). Love the whole journey and especially your note at the end about intention and care. I simply want to build something that helps with my personal life and the friends around me. It's always been this really. Many engineers like big scale and highly performant systems -- e.g. "we process billions of transactions a day" is something that they'd be proud of. When I joined...

I used to build products at Facebook, including extremely core privacy and chat features. Launching is honestly a massive coordination act over anything else -- having a timeline of what's going to happen on the day, what needs to happen before (anything you need to build, fix, but even more importantly your comms plan, where you'll be sharing news, who you'll reach out to for support). On the...

Agreed that UI needs to change. But I'm not bullish on going pure chat. Having to type text can be incredibly inefficient too, and LLMs are so prone to hallucinating intent incorrectly that pure chat interfaces are more likely to get things wrong instead of right. Booking a meeting at the wrong timeslot is annoying at best and unprofessional at worst. You really want ways for the user to...