Top Slack Companies (2,033)

Built In is helps professionals discover companies, understand what it’s like to work there, and find their next opportunity. For candidates, we bring together company information, workplace insights and open roles to provide a balanced view of the employee experience, including both the strengths and challenges of working at a company. For employers, Built In provides intelligence and tools to...

Datadog (NASDAQ: DDOG) is a global SaaS business, delivering a rare combination of growth and profitability. We are on a mission to break down silos and solve complexity in the cloud age by enabling digital transformation, cloud migration, and infrastructure monitoring of our customers' entire technology stacks. Built by engineers, for engineers, Datadog is used by organizations of all sizes...

Moov is a payments infrastructure platform making it easy to accept, store, send, and spend money all from a single, elegantly-designed API. Instead of stitching together multiple vendors, software companies simply add Moov to their products to get the latest in payment technology, user onboarding, licensing, compliance, and more.

IG North America is home to tastytrade, tastylive, tastyfx, and tastycrypto—a family of brands built to democratize trading and empower individual investors. Founded in Chicago by the creators of thinkorswim, acquired by London-based IG Group in 2021, we combine startup innovation with the backing of a global fintech leader with 50+ years of experience. From our headquarters in Chicago's Fulton...

Mastercard powers economies and empowers people in 200+ countries and territories worldwide. Together with our customers, we’re building a resilient economy where everyone can prosper. We support a wide range of digital payments choices, making transactions secure, simple, smart and accessible. Our technology and innovation, partnerships and networks combine to deliver a unique set of products and services that help...

American medicine is the best in the world. But the American healthcare system is challenged by high administrative costs that burden patients, health systems, and insurance companies with unnecessary expenses. We are focused on addressing those challenges. We use GenAI to improve the most pressing financial pain points in the revenue cycle. We’re one of the first companies to deploy GenAI...

Together, we power advertising that enables billions of people to stay informed, entertained, and connected. We introduce them to new ideas, products, and services that make their lives better. And we help media owners of all sizes realize their full potential. That’s a lot — that’s the power of advertising. But it’s only possible with great technology. And that’s where Magnite...

We started as a company that turned phones into walkie-talkies. Today, we modernize instant voice communication with our industry-leading push-to-talk technology to help mobile workers meet quickly changing, urgent, real-world challenges. We have the highest-rated walkie-talkie app, with over 8 billion messages sent per month and 170 million users in industries such as transportation, retail, construction, hospitality, healthcare, and more....

Agero is a leading provider of driver assistance, accident management, consumer affairs support and connected vehicle services for stakeholders across the automotive industry, including the world’s largest automakers, auto retailers, insurers, rideshare providers and other brands. As the driving force behind mobility support throughout all points in the vehicle ownership journey - from purchase to maintenance and breakdown to resell or...

Crexi is reimagining commercial real estate with an AI-powered platform built to deliver smarter, more efficient solutions at every stage of the deal lifecycle. From real-time data and market insights with Crexi Intelligence, to targeted property marketing and seamless deal management through Crexi PRO, and a transparent, time-bound bidding experience with Crexi Auction— Crexi enables users to evaluate opportunities, maximize...

Flex, an NYC-headquartered FinTech company, has created a trusted rent payment experience. It’s hard to believe that it’s 2024 and paying rent on time is expensive, inflexible, and difficult; we’re here to change that! We enable our users to pay rent throughout the month on a schedule that better fits their finances and budget, while also helping them build credit....

Headquartered outside of Boston, Mass. and founded in 2001, Vestmark is a leading provider of portfolio management/trading solutions and outsourced services for financial institutions and their advisors, enabling them to efficiently manage and trade customized client portfolios through an innovative SaaS platform. Supporting over $1.5 trillion in assets and more than 5 million accounts, Vestmark is a partner to some...

At any given time, 16 million Americans are experiencing a crisis that requires urgent help from our legal system or government. The right assistance could transform their lives. But today, most never get it. Atticus makes it easy for any sick or injured person in crisis to get the life-changing aid they deserve. In just three years, we’ve become the leading...

Traditional firms rely on interviews, retroactive documentation, and billable hours. Onshore applies AI at the point of substantiation, providing documentation tied directly to source data and pairing it with expert review. The result is defensible, audit-ready work delivered in weeks, not quarters. We help companies claim R&D Tax Credits, 179D Deductions, and Cost Segregation with proof, not process. 500+ companies have trusted Onshore...

Build the expertise the rest of the industry will follow. Fieldguide is establishing a new state of trust for global commerce and capital markets by automating and streamlining the work of assurance and audit practitioners. We build agentic software for the people who enable trust between businesses. This is where deep professional expertise meets cutting-edge AI. Our team is reimagining how the...

Relativity Space is on a mission to better connect humanity to space and the universe beyond our planet. Our medium-to-heavy lift reusable rocket, Terran R, will deliver customer payloads to orbit, meeting the growing demand for launch capacity. But that’s just the start. Achieving commercial success with Terran R will unlock new opportunities to advance science, exploration, and innovation, pioneering progress that...

Launch, pivot, or accelerate your career with an organization invested in your success. Together, we’re transforming the homeownership journey and redefining what it means to serve clients with heart, innovation, and impact. At Redfin, your work will help make the dream of owning a home more accessible and equitable for everyone. You bring the relationships; we handle the rest. Our...

Over the last 15 years, we’ve grown from a startup to a market-leading organization with over 150 team members, and we’ve created an award-winning culture that makes this company an amazing place to work. We've been ranked on multiple best places to work lists including the 2026 BuiltIn Chicago rankings.

Nasuni is a leading unstructured data platform for enterprises where file data is mission-critical for both people and AI. We power the operational file layer where work happens — helping organizations manage, protect, and activate data so teams can work smarter, reduce costs, and operate securely without limits. Built on a patented architecture that fuses cloud object storage with enterprise...

Deterministic rails underneath. Agents on top. Built for the GP who gets the number, asks the next question, and trusts the answer.