Posh scales real-world connections with Twilio

Challenge

Posh— a next-generation event management and social platform— sought a secure, scalable way to authenticate users and block fraud. The company needed to power high-volume messaging in order to drive real-world community engagement.

Solution

Twilio’s Verify and Lookup APIs block fraud and ensure only real users join the platform, while Twilio Programmable Messaging powers reliable, large-scale event communication for 6M users. Plus, Twilio’s Personalized Support service helps Posh scale strategically.

Social media was supposed to be a tool to bring people closer together—breaking down barriers, shrinking distances, and creating endless ways to connect. But for Gen Z, the first digital-native generation, these platforms have often delivered the opposite.

Curated personas, passive scrolling, and surface-level interactions have created a huge gap between digital presence and real human connection. Among the outcomes of this gap is loneliness, one of the defining public health challenges of our time. 

Posh wants to bring an end to the loneliness epidemic. What began as a white-label ticketing tool for nightlife events transformed into something much more ambitious—a next-generation social platform that encourages people to get off their phones and engage with each other in person. 

To support their mission, scale securely, and build trust between event organizers and attendees, Posh turned to Twilio to power safe, authentic, and engaging communication.

Building real communities requires real humans

Posh began as a simple tool built by two college students to automate text invites for their nightlife events. Eli Taylor-Lemire, Co-Founder and Chief Product Officer, says the idea came when a friend was texting people all day to come to a party. “We thought we could make a script that automates that process,” Taylor-Lemire recalls. 

For the first few years, Posh focused on event ticketing. But when the Covid pandemic put an end to live events, the company decided to build out the platform for anyone to use. As the world learned how to move forward, Posh pivoted from ticket-buying to community-building. 

“The element of community is important,” Taylor-Lemire says. ”People go to events now to socialize in a way that's not online, where they feel like they're having authentic human interactions and are a part of a community.” 

What is the one essential ingredient to building communities? Trust.

As Posh’s user base swelled, so did attempts to abuse the platform. Early on, the company’s in-house authentication system suffered a massive SMS pumping attack where fraudulent traffic triggered thousands of fake verification requests.

“We scrambled to figure out a plan,” recalls Ethan Harsh, Senior Software Development Engineer at Posh. “We had fraudulent messages flooding in from all over the world.”

That’s when they partnered with Twilio and integrated Verify, Lookup, and Programmable Messaging to power the next generation of real-world connection.

A partnership built on authenticity

By replacing their custom SMS authentication with Twilio Verify Fraud Guard—a fully-managed solution backed by intelligent fraud detection—Posh was able to halt the SMS pumping attack mid-stream.

“Twilio Verify stopped the SMS pumping attack right in its tracks,” Harsh says. From that moment on, Verify became a core part of the platform’s security architecture. 

“With Fraud Guard, we recently blocked 97,000 bad attempts and saved $15,000 in a single month,” Harsh says.

But verification isn’t just about cost; it’s also about trust. In a platform built around real-world connection, authenticity is everything. That’s where Twilio Lookup came in.

As the platform grew, Posh noticed some accounts behaving like bots, even after passing SMS verification. So they implemented Twilio Lookup with Line Type Intelligence to identify and block Voice over Internet Protocol (VoIP) and other non-mobile numbers. 

“It is an absolute necessity for us to be sure that everybody on the platform is a real human and not a robot,” says Harsh. “Twilio Lookup has had an immediate positive impact on the platform and we've already blocked more than 50,000 bots masquerading as humans.”

Twilio Verify authenticates users and blocks fraudulent signups, while Lookup helps detect if a phone number is present, and whether a user is a real person or a bot. These layers of protection ensure that only real humans can engage, and that communication—especially through their flagship feature, Text Blasts—is both safe and meaningful.

Blast off: Programmable Messaging at scale

Once users are verified, the next step is engagement. That’s where Twilio Programmable Messaging powers one of Posh’s most prolific features: Text Blasts.

Text blasts allow event organizers to send personalized updates, announcements, and invites to their communities. As the Posh platform grew, so did demand, eventually reaching over 1 million messages per day.

How was Posh able to build a scalable system? By adhering to a few main principles:

• Asynchronous processing and retries. Posh makes sure messages are processed asynchronously in the background and the system has built-in retry mechanisms for every message.

• Isolated state management. Posh enforces isolation by utilizing state machines or queues in between each step. They also host their messaging system separately from their main customer facing API, which allows the SMS workload to scale separately.

• Robust error handling and record keeping. Twilio provides data on every message sent enabling Posh to  identify any systemic issues that occur while sending a large number of messages. Meticulous record-keeping ensures a high deliverability rate.

“It's not just about sending messages,” says Harsh. “It's about creating opportunities for people to come together.”

Delivering messages that drive real connections, not just clicks

The results from the Posh and Twilio partnership speak to both technical performance and human outcomes:

• 3.8 million phone numbers verified as active mobile devices with Twilio Verify Fraud Guard

• 50,000 bots blocked using Lookup Line Type Intelligence

• Over 1 million messages sent daily with robust error handling and asynchronous processing

• 97% SMS deliverability, with no major outages

• Increased text blasts conversion rates lead to more in-person attendance and engagement

Behind the scenes, Twilio’s Personalized Support service provides technical guidance, architectural advice, and real-time help via dedicated Slack channels. This allows engineering teams to scale quickly while staying focused on user experience.

“Without Personalized support, we wouldn't be able to be as strategic with implementation,” said Taylor-Lemire. 

But perhaps the most compelling result is the platform’s contribution to solving loneliness—bringing people together, not just online but in real life.

Helping millions of people make friends, find events, and feel seen

In an era where most platforms optimize for screen time, Posh is doing something different: using technology to spark real human connection. With Twilio, they’ve built a secure, scalable, and engaging system that empowers 6 million users to find their people, show up in real life, and party like there’s a better tomorrow.

From fraud prevention to global messaging at scale, Twilio has been a trusted partner to Posh at every step of the way by giving it the tools, reliability, and support to build something truly special. In fact, the team is now testing Rich Communication Services (RCS) and WhatsApp integrations to further personalize and enrich the messaging experience.

“RCS feels very interactive,” says Taylor-Lemire. “We're excited about it because we always want to be building on the cutting edge of each vertical. And in the SMS vertical, RCS seems like the new thing.”

Together, Posh and Twilio are proving that with the right technology—and reasons—digital connection can bring people together and build real-world communities.