Senior Software Engineer - 99Pledges

About the Role

99Pledges a fundraising technology platform that powers online donation campaigns for organizations, teams, and individuals through our flagship product and through white-label deployments for partners. We process real money at scale, so correctness, reliability, and security are core to everything we build.

We're looking for a Senior Software Engineer who thrives in a mature, production Rails codebase, cares deeply about payment integrity, and can own features end-to-end from database schema to background jobs to the user-facing UI.

What You'll Work On

• Core fundraising platform : Campaigns, participants, donations, and the reporting and metrics that fundraisers rely on.
• Payment processing : Integrations with multiple payment providers (credit card, PayPal, and ACH/EFT), including automatic payouts, payment requests, and reconciliation.
• Multi-tenant white-label system : Branding, feature flags, and configuration that let partners run the platform under their own identity.
• Fraud prevention & trust : Fraud detection, device fingerprinting, and abuse mitigation that keep donors and organizations safe.
• Background processing : Reliable email delivery, data exports, and scheduled metric calculations.

Tech Stack

• Backend : Ruby on Rails 7, Ruby 3.1
• Database : PostgreSQL (production), with careful attention to migrations and denormalized/calculated fields for performance
• Frontend : HAML, SCSS, Bootstrap, jQuery
• Background jobs : Delayed Job (Active Record backend)
• Payments : Braintree, PayPal, Dwolla
• Infrastructure : Heroku, AWS S3, Redis
• Email : Postmark
• Monitoring : Honeybadger (errors), New Relic (performance), Datadog (migrating to)
• Analytics/experimentation : PostHog

What We're Looking For

Required

• 3+ years building and maintaining production web applications, with strong Ruby on Rails experience.
• Solid grasp of relational database design, query performance, and safe migrations against large production tables.
• Experience integrating third-party APIs, ideally payment processors, and an appreciation for the failure modes that come with them (retries, idempotency, webhooks, reconciliation).
• A test-first mindset, you write well-tested code and treat correctness and edge cases as first-class concerns.
• Comfort working across the stack, including server-rendered views and front-end interactivity.
• Strong communication skills and the ability to explain technical tradeoffs clearly.

Nice to Have

• Experience with payment/fintech systems, PCI considerations, or handling money in software.
• Familiarity with multi-tenant / white-label architectures.
• Experience with background job systems and asynchronous processing at scale.
• Exposure to fraud detection or trust & safety systems.
• Experience with feature flagging and A/B experimentation (e.g., PostHog).

How We Work

• We review designs before writing code and favor explicit, well-engineered solutions over clever ones.
• We prefer DRY code, thorough testing, and small, reviewable changes.
• We take production seriously: careful migrations, monitoring, and a bias toward correctness — because we handle donations that matter to real people and organizations.

Why Join Us

You'll work on software that helps organizations raise money for causes they care about, with a small team where your work has direct, visible impact on both the product and the people who depend on it.

Our Values at the company

• Humility: We acknowledge that the path to getting to the right answer involves being wrong along the way. We have strong beliefs which are weakly held. We actively seek new ideas and believe we can learn from anyone at any time.
• Honesty: We are truth seeking in our approach to business problems. Business is a repeat game and we believe that human relationships generate alpha. We understand that trust is earned over a lifetime and can be lost in an instant.
• Hunger: We play to win. We hold ourselves to high standards and will not be outworked. We take pride in having a deep sense of responsibility to ourselves, each other, our partners, and our customers. We believe to whom much is given much is expected.
• Horizon: We seek to build a generational software company. This will take decades. We manage our expectations and those of our partners to take advantage of the 8th wonder of the world - compounding growth.

How We Use AI in Our Hiring Process: To ensure transparency, we want candidates to know that the company uses Artificial Intelligence and AI-enabled tools to assist with screening, reviewing, organizing and highlighting profiles and applications that match the key requirements for each role.

AI does not make hiring decisions: Every application is reviewed by a member of our team, and all decisions throughout the process are made by humans. We use AI to support efficiency and consistency, not to replace human judgment. We are committed to a fair, thoughtful, and equitable experience for every candidate.