GTM Sauce

B2B · open-source DocSend alternative

How Papermark grows

9 tactics and 21 figures from 1 interview.

papermark.com

Papermark is an open-source, bootstrapped alternative to DocSend for sharing documents and data rooms, run by a husband and wife team. It started from a tweet that tested demand, grew through public posts and a free plan, and took off once it matched the incumbent's key features, reaching about $3M ARR.

Summary written 2026-11-11 from the tactics below. Figures are as founders stated them.

About Papermark

What it is
Open-source document sharing and virtual data rooms with custom domains and full branding, positioned as a DocSend alternative
Who it's for
Teams sharing documents and data rooms, mostly people who already use a comparable tool
Business model
Commercial open source; free plan forever plus paid plans (free trials available)
Pricing
Free plan, kept indefinitely; Paid plans at a price point the founder says matches or beats incumbents (no figures given)
Launched
2023
Team
Two co-founders (Marc Seitz and his wife, 50/50); small team
Funding
bootstrapped
Outcome
Independent, bootstrapped and profitable; ~$3M ARR, ~3,000 paying customers, 60,000+ teams

As described in the interviews, not independently verified.

Papermark's 9 tactics

Papermark · B2B · open-source DocSend alternative

Tweet got 450 likes and 95K+ views; the launch went viral and users asked to pay

Instead of building first, the founder (at his wife's suggestion) wrote a single tweet pitching an open-source DocSend alternative. The bar: if people like, share and comment, build it over the weekend. The tweet got traction immediately (450 likes, 95,000+ views per host), so he built the first version that weekend and shipped it, then posted the launch, which went viral again. He kept building on nights and weekends until the first customers asked if they could pay. He had only ~1,000 X followers at the time.

Workedvalidationfounder-brand
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

Founder calls it a differentiator; no numbers

Rather than changing user behavior, Papermark took its own spin on the incumbent's product through personalization and professionalization: a custom domain out of the box and full branding of the look and feel of data rooms and shared documents, while incumbents put their own brand front and center. Roadmap is driven by the founder's own experience with these tools and their minimum feature set.

Unknownfeature-developmentpositioning-niche
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

Founder says most growth is organic and word of mouth; 60K+ teams

Papermark's 60,000+ teams share many document and data-room links. Unless a team adds a custom domain, links default to papermark.com. Recipients who have never heard of Papermark get a link forwarded, see the site, and check whether it fits them. Because most already use a comparable tool, they need no education; a good experience as a viewer leads to a good experience as an admin.

Workedproduct-viralityword-of-mouth
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

Now ~$3M ARR; founder credits timing and a known, disliked incumbent

Picked a space nobody was building open source in: DocSend-style document sharing and data rooms. Rode the 2023 wave of commercial open-source alternatives to older SaaS (e.g. an open-source Calendly alternative). DocSend was known to everyone, disliked, and had stopped iterating after Dropbox acquired it. Customers usually already use a comparable tool, so they need no education. He urges founders to look at saturated, non-AI markets ripe for disruption rather than AI products that need behavior change.

Workedpositioning-nichemarket-selection
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

First ~1,000 GitHub stars in 1-2 months; 8,900 stars now

Papermark was part of a small, informal commercial open-source community (many part-German founders) whose members backed each other's posts early on. Being open source meant everything, down to each line of code, was already public, so they shared wins and losses roughly every month; people like following a journey. The first ~1,000 stars came within 1-2 months off viral X posts.

Workedfounder-brandcommunity
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

One LinkedIn post reached ~250K views; helps but can't be tracked to revenue

Early traction came from X, but none of Papermark's customers are on Twitter; most are on LinkedIn, so founder posting shifted toward LinkedIn. One post reached about 250,000 views. LinkedIn is not a trackable conversion channel, but he says it helps because many customers are there. X is still where he is most active personally.

Unknownfounder-brand
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

Under $1M for ~2 years; then $1M to $2M in four months once parity hit

Buyers already knew what they wanted from incumbents; until Papermark had the one or two features they were hoping for, they still went to a competitor. The founder says differentiation does not matter until you are feature-complete, because nobody wants a half-baked product. Once the product was complete and offered at the same price point, switching became a no-brainer. Most growth came after that point.

Workedfeature-developmentpricing
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

~100 signups a day and ~100 new paying customers a month

Papermark offers a free version; some signups move into free trials and others stay free forever, which the founder is fine with, aiming to make getting started as easy as possible. DocSend eventually killed its free version, and none of the top players in the market offer one, which Papermark treats as an opening.

Workedpricingpositioning-niche
Top Founders with Nathan Latka · 2026-11-10

Papermark · B2B · open-source DocSend alternative

Bootstrapped and profitable at ~$3M ARR; never considered quitting

Before Papermark, both founders had good jobs and built a sizable savings buffer that carried them through the first year. The company is run by two co-founders, Marc and his wife, split 50/50 to avoid friction. No outside funding. Profits are largely reinvested in the product and in building distribution channels; they now pay themselves a proper salary.

Workedfinancingteam-process
Top Founders with Nathan Latka · 2026-11-10

Papermark by the numbers

MetricValueContextSaid in
arrUSD 3M
approximate
Current ARR; also the title figureTop Founders with Nathan Latka
2026-11-10
13:21
arrUSD 3.5M
goal
Original goal for 2026Top Founders with Nathan Latka
2026-11-10
13:21
arrUSD 4M–4.5M
projection
Expected finish for 2026 at the current growth rateTop Founders with Nathan Latka
2026-11-10
13:21
arrUSD 5M–6M
estimate
Host's push; guest corrected to $5M as the best caseTop Founders with Nathan Latka
2026-11-10
13:35
arrUSD 5M
projection
Best-case ('wishful') finish for 2026Top Founders with Nathan Latka
2026-11-10
13:41
revenueUSD 1M
approximate
Broke $1M; about two years after launchTop Founders with Nathan Latka
2026-11-10
12:12
revenueUSD 2M
approximate
Broke $2M four months after $1MTop Founders with Nathan Latka
2026-11-10
12:20
customers3,000 customers
approximate
Paying customersTop Founders with Nathan Latka
2026-11-10
7:43
users100 signups/day
approximate
New signups per day, mostly onto the free plan; a portion start free trialsTop Founders with Nathan Latka
2026-11-10
9:09
new customers100 customers/month
approximate
New paying customers last monthTop Founders with Nathan Latka
2026-11-10
9:39
users60K teams
approximate
Over 60,000 teams in total, free and paidTop Founders with Nathan Latka
2026-11-10
10:01
count8,900 GitHub starsStars on Papermark's open-source GitHub repositoryTop Founders with Nathan Latka
2026-11-10
3:04
count62 contributorsContributors to the GitHub repository; guest says most code is his, with AI tools (Cursor, CodeRabbit) showing upTop Founders with Nathan Latka
2026-11-10
3:04
time to milestone1–2 months
approximate
Time to the first ~1,000 GitHub stars, off viral X postsTop Founders with Nathan Latka
2026-11-10
3:26
count450 likesper post
approximate
Likes on the demand-test tweet for an open-source DocSend alternativeTop Founders with Nathan Latka
2026-11-10
0:37
views95K viewsper post
approximate
More than 95,000 views on the demand-test tweetTop Founders with Nathan Latka
2026-11-10
0:37
followers1,000 followers
approximate
Marc Seitz's X following around launch; it took a long time to pass 5,000Top Founders with Nathan Latka
2026-11-10
5:08
views250K viewsper post
approximate
One viral LinkedIn postTop Founders with Nathan Latka
2026-11-10
4:50
domain rating73 score
estimate
SEO domain rating per host's tool (Ahrefs)Top Founders with Nathan Latka
2026-11-10
9:41
count5,200 organic clicks/month
estimate
Organic search clicks per Ahrefs; host says low for a 73 DR. Guest says most growth is still organic/word of mouthTop Founders with Nathan Latka
2026-11-10
9:41
ownership50%Each co-founder (Marc and his wife) owns halfTop Founders with Nathan Latka
2026-11-10
11:15

Topics

Interviews