F

Finix

Developer-friendly API for payment processing

Senior Software Engineer

Full-Time
$150k - $220k/yr
Mid, Senior, Expert
San Francisco, CA, USA
In Person
Software Engineering

About the job

Requirements
  • Have 4+ years of experience building and designing systems with several lifecycles
  • Extensive experience implementing secure APIs, highly available and observable services
  • Led and mentored more junior software engineers
  • Kept tight control on multiple competing priorities and have strong ability to multitask
  • Raised the bar on every project you were involved in
Responsibilities
  • Deep dive into our customers’ needs, and work with product management to define new services
  • Own the technical vision, implementation, best practices and infrastructure within your domain
  • Develop close relationships with product management and peer engineers
  • Become an expert in your payments domain and mentor junior software engineers
  • Proactively improve our architecture, frameworks, tooling, automation, and best practices

About the company

Finix provides a payment processing platform for software platforms, offering a developer-friendly API that lets SaaS providers, marketplaces, and e-commerce sites accept payments, handle merchant onboarding, and manage payouts. The API integrates into existing software to streamline payments and reduce operational complexity. It earns revenue by charging fees for API usage and related services, such as transactions or subscriptions. Finix differentiates itself by delivering a clean, easy-to-integrate payment solution that emphasizes reliability, security, and scalable payout and onboarding capabilities, enabling clients to grow revenue and cut costs instead of building payments from scratch. The company’s goal is to help software platforms run their payments efficiently, unlock more revenue from payment operations, and reinvest that income into their core products and teams.

Company Size

201-500

Company Stage

Series C

Total Funding

$200.5M

Headquarters

San Francisco, California

Founded

2015

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Simplify Jobs

Simplify's Take

What believers are saying

  • Contractor Plus chose Finix on June 30, 2026 for embedded contractor payments.
  • Change used Finix on July 30, 2026 to onboard nearly 10,000 nonprofits.
  • Headcount reached 177 by March 2026, showing growth after the October 2024 Series C.

What critics are saying

  • Stripe, Adyen, and Shift4 crush Finix on scale and distribution by 2026.
  • Payments margins stay exposed to processor switching, chargebacks, and partner dependency.
  • A major underwriting or compliance failure could trigger a trust collapse overnight.

What makes Finix unique

  • Finix owns online, in-store, and payout workflows under one API.
  • September 2026 custom Android terminal apps deepen its embedded payments control.
  • Plaid integration and no-code onboarding reduce merchant setup friction since March 2026.

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Benefits

Competitive compensation

Generous PTO

Flexible health plans

Coverage for dependents

Inclusive parental leave

Growth & Insights and Company News

Headcount

6 month growth

0%

1 year growth

0%

2 year growth

1%
Yahoo Finance
Sep 28th, 2026
Finix lets businesses run custom Android apps on payment terminals

Finix has launched a new feature allowing businesses to deploy custom Android applications on supported payment terminals. This enables companies to combine their specific workflows with integrated payment processing on a single device, creating a seamless, branded in-person customer experience. The innovation embeds payment functions directly into business-specific applications, streamlining operations and aligning the checkout process with individual business needs. This development reflects the growing trend towards customisable and flexible payment solutions in the digital payment sector. By integrating payment processing into bespoke applications, businesses can maintain consistent branding throughout the customer journey whilst simplifying their operational technology stack.

Business Insider
Sep 10th, 2026
Finix expands in-person payments suite with two new devices.

Finix expands in-person payments suite with two new devices. Sep. 10, 2026, 09:00 AM SAN FRANCISCO, Sept. 10, 2026 (GLOBE NEWSWIRE) - Finix, the full-stack payment processor enabling businesses to accept and send payments online and in-store, today announced the addition of a new Android-enabled payment tablet to its suite of in-person payment devices. The two devices give businesses more choice in how they accept card-present payments. The touchscreen tablet offers a larger, portable interface for mobile or countertop checkout, while the payment terminal provides a compact option for fixed checkout stations. Key features of the new devices include: * PAX A3700: A customer-facing Android-enabled payment tablet designed for retail checkout. Its 7-inch touchscreen can connect to a hub or operate independently as a mobile payment device. It accepts contactless, chip and magnetic-stripe payments and connects through Wi-Fi, 4G LTE or Ethernet with an optional hub. * PAX A35: A compact Android-enabled device built for fixed, customer-facing checkout. Its 4-inch touchscreen and tactile keypad support contactless, chip and magnetic-stripe payments, with Wi-Fi, Ethernet and Bluetooth connectivity. "There is no one-size-fits-all checkout process, especially as businesses expand across locations and use cases," said Richie Serna, co-founder and CEO at Finix. "These devices give our customers more ways to build the in-person experience that works for their business." Transactions processed through both devices flow into Finix, where businesses can manage reporting, reconciliation, refunds, customer data and other payment operations alongside online transactions. The PAX A3700 and PAX A35 are available to order through Finix. For more information about Finix's suite of in-person payment solutions, visit https://finix.com/payment-terminals. About Finix Finix delivers everything businesses need to build world-class payment experiences. From fast-growing startups and SaaS platforms to large-scale ecommerce companies, Finix's universal API and intuitive dashboard enable businesses to accept and embed payments quickly, automate workflows, enhance customer experiences and accelerate revenue growth. Learn more at finix.com. Media Contact Markets Insider and Business Insider Editorial Teams were not involved in the creation of this post.

Financing Your Way
Aug 6th, 2026
Finix revamps dashboard to simplify payment operations.

Finix revamps dashboard to simplify payment operations. Finix launches a redesigned merchant dashboard to simplify transaction management and speed up back-office payment operations. Curated by Financing Your Way from original reporting by Finextra - Lending. Summary is AI-assisted and editorially reviewed - see its editorial standards. Finix has overhauled its merchant dashboard to streamline how businesses manage their payment operations. For retailers and operators, this means less time digging through complex data and more time focusing on sales. The updated interface centralizes transaction monitoring, dispute management, and settlement tracking into a single view. This is particularly useful for businesses running multi-channel operations across both physical storefronts and e-commerce sites. The new dashboard introduces better filtering tools and more intuitive navigation. You can now quickly identify why a specific payment failed or check the status of a customer refund without needing technical support. For businesses that offer financing or high-ticket items, having real-time visibility into cash flow and settlement cycles is critical. The goal of this update is to reduce the administrative burden on your back-office staff. By simplifying the 'money-in, money-out' process, the platform helps you reconcile books faster and respond to customer payment inquiries with more accuracy. Who else is covering this

Finix
Aug 6th, 2026
Finix launches redesigned Dashboard to simplify payment operations.

Finix launches redesigned Dashboard to simplify payment operations. New dashboard delivers a more intuitive experience with smarter navigation, greater flexibility and streamlined workflows. SAN FRANCISCO, August 6th, 2026 - Finix, the full-stack payment processor enabling businesses to accept and send payments online and in-store, today announced a redesigned dashboard that makes it easier for businesses to manage payments. The new dashboard introduces improved search and filtering, deeper customization and streamlined navigation, all within a faster, more intuitive interface built around how customers work every day. Every day, businesses rely on the Finix Dashboard to onboard merchants, monitor transactions, manage payouts, support customers and more. As businesses have taken on more sophisticated payment operations, the tools used to support them have become increasingly complex. Built through extensive customer research and feedback, the redesigned dashboard makes it easier to navigate payment operations, quickly find critical information and personalize the platform around the way each business works, removing friction from everyday payment workflows while preserving the powerful capabilities customers already rely on. Beginning today, Finix customers can take advantage of: * Smarter search and filtering: Quickly find merchants, transactions and other records using the fields customers rely on most, with one-click filters that make navigating large datasets faster. * A personalized workspace: Customize homepages, save frequently used filters, pin pages for one-click access and configure tables to match individual workflows. * Simplified navigation: Access merchant account and identity information from a unified merchant view and reach commonly used pages with fewer clicks. * A faster, cleaner experience: Benefit from faster load times, redesigned detail pages, improved layouts and optional dark mode for greater usability. "We are always thinking about how we can improve the customer experience, whether it's for founders or back-office power users," said Finix CEO and co-founder Richie Serna. "Our Product and Design teams listened to and incorporated a lot of customer feedback that makes it easier and faster for customers to navigate and use our dashboard." Early customer feedback has highlighted the dashboard's streamlined design and seamless transition, with some already rolling it out across their organizations. "Whenever a platform redesign is announced, you naturally expect there to be a learning curve or for some of the features you rely on every day to change," said Dave Lowensohn, COO & co-founder at Candid Wholesale. "With the new Finix Dashboard, everything we depend on is still there, but it's faster, easier to navigate and helps our team find the payment information we need much more quickly. We were able to jump right in without missing a beat, which made the transition seamless for our team." The redesigned dashboard underscores Finix's mission to make modern payment infrastructure more accessible for businesses. By combining powerful payment capabilities with tools built around real customer workflows, Finix helps businesses simplify payment operations and deliver exceptional experiences for their customers. About Finix Finix is a full-stack payment processor enabling businesses to accept and send payments online and in-store. From startups to publicly traded companies, Finix offers everything needed to deliver a world-class payments experience across the US and Canada. Leading software platforms and merchants use Finix's universal payments API and dashboard to accept payments, automate workflows, enhance customer experiences, and quickly grow revenue. To learn more, visit www.finix.com or contact its sales team.

Financial IT
Jul 31st, 2026
Change and Finix simplify corporate giving through embedded payouts.

Change and Finix simplify corporate giving through embedded payouts. * Payments * 31.07.2026 09:34 am Change, the leading compliance and donation infrastructure platform for charitable fundraising, has partnered with Finix, the full-stack payment processor enabling businesses to accept and send payments online and in-store. Together, the companies have built a seamless, white-labeled payout experience that enables businesses to launch charitable giving programs while securely routing donations to nearly 10,000 nonprofits across the United States. As more businesses look to incorporate charitable giving into the customer experience, many encounter significant legal, compliance and operational hurdles. Change helps businesses navigate this complexity by supporting nonprofit verification, applicable state registrations, donation processing, reporting, and charitable giving compliance through its technology and operational infrastructure. To complete that experience, Change needed payment infrastructure that could operate invisibly behind the scenes. Unlike traditional payout models, many nonprofit recipients have never interacted with Change before receiving funds, making trust just as important as the payment itself. Using Finix's white-labeled payout infrastructure, Change embedded nonprofit bank onboarding directly into its platform and customized statement descriptors to display "Our Change Foundation," helping recipient organizations immediately recognize and trust incoming donations. As Change's payout volume has grown, Finix has continued to scale alongside the business, providing responsive operational support that keeps donations moving during periods of significant transaction growth. "We collaborated closely with the Finix team from day one of onboarding to get things up and running smoothly," said Steven Traversi, Head of Engineering at Change. "Now, we haven't had to touch this code in years. That lack of ongoing developer maintenance is reason enough to switch to Finix. Beyond that, the platform scales with us, the white-label flexibility protects our brand trust and, if we have questions, knowing someone from Finix will respond quickly gives us total peace of mind." Since partnering with Finix, Change has achieved several measurable operational improvements: * Roughly 10,000 nonprofits successfully onboarded and paid through the Finix platform. * Consistent 24-hour bank account verification to accelerate nonprofit onboarding. * Responsive operational support that keeps large donation campaigns moving during significant payout spikes. * Zero Finix-related customer support inquiries from nonprofit users over the past year. * A scalable payments foundation that allows Change's engineering team to focus on building new capabilities instead of maintaining payment infrastructure. "Change is making it easier for businesses to build charitable giving directly into their products," said Richie Serna, CEO and co-founder of Finix. "By providing flexible payments infrastructure that scales with their business, we're helping them focus on expanding access to corporate giving instead of managing payment complexity."