Episode 35 of The Technical Co-Founder Podcast. Lucas and Luna dive into the story of a bootstrapped B2B SaaS startup called StitchFlow that slashed its AWS bill by 70 percent using spot instances and a custom spot-termination handler. They walk through the architecture: a Kubernetes cluster with priority classes, a Python script that listens for the two-minute AWS termination notice and gracefully drains pods, and the trade-off between cost savings and operational complexity. They discuss when spot instances make sense, how to handle interruptions, and why this approach saved the startup from running out of runway before reaching product-market fit. Along the way, they touch on why many startups avoid spot instances due to fear of instability, and how a well-designed fallback system can turn that fear into a competitive advantage. If you are an engineering founder or CTO trying to stretch every dollar, this episode offers a concrete playbook for cutting infrastructure costs without sacrificing reliability.

#CloudCosts #AWS #SpotInstances #Kubernetes #StitchFlow #BootstrappedStartup #B2BSaaS #TechInfrastructure #EngineeringFounder #CTO #CostOptimization #DevOps #CloudArchitecture #BusinessAndTechnology #FexingoBusiness #BusinessPodcast #TechnicalCoFounder #StartupStrategy

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In this episode of The Technical Co-Founder Podcast, Lucas and Luna explore the practice of chaos engineering — deliberately injecting failures into production systems to uncover weaknesses before they cause outages. They look at how one startup, a real-time payments platform, used controlled experiments like shutting down servers and corrupting data to test its infrastructure. Lucas breaks down the Netflix Chaos Monkey origin story and how smaller companies can adopt the same principles without a full SRE team. Luna asks the hard questions: how do you convince a skeptical CTO to break things on purpose? And what happens when chaos engineering reveals a critical flaw mid-deployment? The hosts also touch on the cultural shift needed — moving from blame-free postmortems to proactive failure testing. By the end, listeners will understand how to run their first chaos experiment, what tools to use (including open-source options like Chaos Toolkit and Litmus), and why the practice is essential for any startup building toward reliability at scale.

#ChaosEngineering #ResilientSystems #NetflixChaosMonkey #SiteReliabilityEngineering #ProductionTesting #InfrastructureAsCode #DevOps #StartupEngineering #FailureTesting #BusinessAndTechnology #TechnicalCoFounder #FexingoBusiness #BusinessPodcast #SystemsThinking #BlameFreeCulture #Observability #IncidentResponse #SoftwareArchitecture

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Episode 33 of The Technical Co-Founder Podcast dives into property-based testing, a technique that flips traditional unit testing on its head. Lucas and Luna explore how one startup—a fintech handling real-time transaction reconciliation—used property-based testing to uncover edge cases their hand-written tests missed. They break down the difference between example-based and property-based approaches, explain the 'for all' mindset, and discuss the tradeoffs in learning curve and tooling. With examples from Python's Hypothesis library and QuickCheck for Erlang, they make a concrete case for when this technique pays off and when it's overkill.

#PropertyBasedTesting #HypothesisLibrary #QuickCheck #SoftwareTesting #EdgeCases #Fintech #StartupEngineering #CodeQuality #Python #Erlang #UnitTesting #FormalMethods #TestingStrategy #BugBounty #ContinuousIntegration #BusinessAndTechnology #FexingoBusiness #BusinessPodcast

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In episode 32, Lucas and Luna explore how a small infrastructure startup called Formal Inc. uses formal methods—mathematical proofs embedded in the development process—to guarantee their core networking library has zero runtime errors. They walk through the specific tool (Dafny), the trade-offs in developer velocity, and why the startup believes the upfront cost saves millions in post-deployment debugging. The conversation also touches on how formal verification is moving beyond aerospace and into commercial SaaS, and why one engineer described it as 'writing tests that the computer can't ignore.' If you've ever wondered whether provably correct code is practical outside of NASA, this episode is for you.

#FormalMethods #Dafny #BugFreeCode #SoftwareEngineering #FormalVerification #StartupEngineering #Infrastructure #CorrectByConstruction #ProgrammingLanguages #StaticAnalysis #ReliabilityEngineering #BusinessAndTechnology #EngineeringPodcast #FexingoBusiness #BusinessPodcast #TechLeadership #CTO #CodeQuality

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In Episode 31 of The Technical Co-Founder Podcast, Lucas and Luna explore how one startup uses cryptographic code signing to ensure every line of code shipped comes from a trusted developer. They walk through the story of a small fintech company that implemented mandatory GPG signing after a supply-chain scare, the technical choices between GPG and Sigstore, and why this practice matters more than ever in the age of automated CI/CD pipelines. Lucas breaks down the real-world tradeoffs: slowed workflows vs. auditability, key management pain points, and the startup-friendly path to zero-trust deployments. Luna pushes back on developer friction and asks whether signing is overkill for early-stage teams. The episode wraps with a practical framework for deciding when your project needs signatures and a concrete recommendation for a low-friction toolchain.

#CodeSigning #Cryptography #DevSecOps #SoftwareSupplyChain #GPG #Sigstore #StartupEngineering #CI/CD #ZeroTrust #Fintech #Security #OpenSource #DeveloperProductivity #BusinessAndTechnology #FexingoBusiness #BusinessPodcast #TechnicalCoFounder #EngineeringCulture

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Episode 30 of The Technical Co-Founder Podcast explores how a small SaaS startup called NightOwl used a seemingly trivial UX feature—a dark mode toggle—as a data collection and growth experiment that transformed their product roadmap. Lucas and Luna break down the specific metrics NightOwl tracked, the A/B test that doubled free-trial conversion, and the engineering decisions behind building a low-risk feature that generated high-signal user data. They discuss why dark mode became a proxy for user engagement, how the team tied toggle usage to retention cohorts, and the lesson for technical founders: sometimes the smallest surface-level changes reveal the most about how your customers actually behave. The episode also touches on why startups should treat every feature, even cosmetic ones, as a hypothesis rather than a deliverable.

#DarkMode #UXDesign #GrowthHacking #SaaS #ProductLedGrowth #FeatureFlags #ABTesting #UserRetention #CohortAnalysis #EngineeringCulture #StartupStrategy #TechnicalCoFounder #FexingoBusiness #BusinessPodcast #BusinessAndTechnology #NightOwl #ProductRoadmap #DataDrivenDesign

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In this episode, Lucas and Luna dig into the story of a logistics startup that replaced its core Python backend with Rust. They walk through why the team decided to rewrite, how they justified the months of engineering time to the board, and the surprising performance gains that followed. The hosts also discuss the hidden costs of a language migration — onboarding friction, ecosystem gaps, and the temptation to rewrite too much. If you've ever wondered whether Rust is right for your team, or how to pitch a rewrite to non-technical stakeholders, this episode offers a concrete case study with real numbers. The hosts also touch on when a partial rewrite makes more sense than a full one, and why the decision often comes down to team culture as much as technical fit. Plus, a quick reflection on whether the effort was worth it — and a reminder of how listener support keeps the show going.

#Rust #Python #Rewrite #Backend #LogisticsStartup #LanguageMigration #Performance #EngineeringCulture #TechnicalDebt #StartupTech #SoftwareEngineering #SystemsProgramming #CodingDecisions #BusinessAndTechnology #FexingoBusiness #BusinessPodcast #TechnicalCoFounder #EngineeringLeaders

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In this episode of The Technical Co-Founder Podcast, Lucas and Luna explore the counterintuitive choice one startup made: saying no to venture capital in favor of bootstrapping to profitability. They focus on the story of a B2B SaaS company that grew to $2 million in annual recurring revenue without taking a dollar from VCs, instead relying on revenue-based financing and customer prepayments. The hosts break down the engineering trade-offs this forced—slower hiring, fewer features, more deliberate architecture—and why the founders believe it made them better builders. They also discuss the psychological shift when no investor is telling you to grow at all costs, and what happens when your only feedback loop is paying customers. A concrete episode for anyone wondering if the VC path is the only one.

#VentureCapital #Bootstrapping #StartupFunding #RevenueBasedFinancing #B2BSaaS #ARR #CustomerPrepayments #Profitability #EngineeringTradeoffs #FounderPsychology #IndieBusiness #BusinessAndTechnology #TheTechnicalCoFounderPodcast #FexingoBusiness #BusinessPodcast #EngineeringCulture #LeanStartup #CashFlow

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Lucas and Luna dig into the story of a twenty-person startup that operated fully asynchronously for eighteen months — no standups, no meetings, just written docs and recorded decisions. They walk through the specific tools the company used, how on-call rotations worked without real-time handoffs, and why the CTO eventually reintroduced a single weekly synchronous hour. This episode covers the real tradeoffs: faster deep work versus slower cross-team alignment, written culture versus the isolation it can create. If you have run a remote team or wondered whether async-first could work for yours, this conversation surfaces the concrete practices and the hidden costs that most async manifestos leave out.

#AsyncWork #RemoteEngineering #EngineeringManagement #DeepWork #WrittenCulture #AsyncFirst #StartupEngineering #NoMeetings #TechLeadership #DistributedTeams #CTO #Slack #Notion #Loom #Linear #Business #FexingoBusiness #BusinessPodcast

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In this episode, Lucas and Luna explore how feature flags — also known as feature toggles — allowed a small engineering team at a fast-growing B2B SaaS startup called SyncFlow to deploy code to production multiple times a day without breaking anything for users. They walk through the specific case of SyncFlow's migration from a monolithic monthly release cycle to a continuous deployment model powered by LaunchDarkly-style flags. Lucas explains how the team used flags to decouple deployment from release, enabling canary launches, instant rollbacks, and gradual rollouts. Luna shares data on how feature flags reduced their incident rate by 70% in the first quarter and cut the time to revert a bad deploy from 40 minutes to under 90 seconds. They also discuss the hidden costs: flag debt, testing complexity, and the discipline required to clean up flags. The episode ends with a practical framework for deciding when to use a feature flag versus a branch or an environment toggle. Perfect for CTOs and engineering leads looking to ship faster without breaking production.

#FeatureFlags #ContinuousDeployment #SoftwareEngineering #TechLeadership #DevOps #LaunchDarkly #B2BSaaS #SyncFlow #CanaryRelease #FlagDebt #DeploymentStrategy #IncidentManagement #EngineeringCulture #BusinessAndTechnology #TheTechnicalCoFounderPodcast #FexingoBusiness #BusinessPodcast #Podcast

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