Tony St. Pierre
Code. Reflect. Evolve.
Mental Models for the Stoic Engineer
Think like a philosopher. Build like a strategist. Ship like a Stoic.
When the sprint slips. When the system shakes. When clarity goes quiet. You need more than code. You need a way to think that holds under pressure.
Mental models, sharpened by Stoicism and stress-tested in the real world, are built for devs who lead with calm and move when it matters.
If a thing is humanly possible, consider it to be within your reach.
— Marcus Aurelius
Why This Exists
Modern engineers live in noise.
Deadlines pile up. Pings blur focus. Specs shift mid-sprint.
Systems stay uncertain. Speed rules. Reflection fades. Burnout spreads.
We debug systems, but we rarely debug ourselves.
This guide is for that. Not therapy. Not theory.
It's a way to think clearly when everything breaks.
An operating system for engineering under pressure.
Together, they form a mental architecture built to hold when everything else breaks.
A way to build well, even when the ground shifts.
What Is a Mental Model?
A mental model is a portable principle.
It simplifies complexity. It sharpens judgment.
It teaches you how to think, not just what to do.
You don't memorize them. You install them. You train them. Then you reach for them without hesitation under pressure.
What Is Stoic Engineering?
Stoicism isn't cold. It's clear. It doesn't kill emotion. It steadies it. It trains you to move with virtue when the pressure's high and the control's gone.
"First say to yourself what you would be; and then do what you have to do." - Epictetus.
A Stoic engineer doesn't panic. They observe. They orient. They build systems and decisions that last.
These four domains form the Stoic foundation. They shape how we see, how we build, and what our work says when we're no longer there to explain it.
I. Patterns of Perception
How Stoics See Under Pressure
"It's not things that disturb us, but our judgment about things." - Epictetus.
Perception is the first domino. Miss it, and everything after tilts. These models steady your lens so your moves don't veer off-course.
The Map Is Not the Territory
Specs aren't the system. Diagrams don't ship.
The Stoic engineer doesn't follow the map; they test the ground until it holds.
- Debugging: Is the bug in the code, or in the way I'm looking at it?
- Onboarding: Don't carry old truths in blind. Check what still holds.
- Reviews: Don't ask if they meant well. Ask if it holds up.
First Principles Thinking
Cut it down to what's real. Rebuild from what won't fold under pressure.
Assumptions bend. Principles stay put.
- In design: What has to be true for this to work, no matter what?
- With legacy: Why was this built like this, and does that reason still stand?
- Under pressure: Don't chase edge cases. Lock down the core.
Systems Thinking
No bug shows up alone. No metric moves without something behind it.
The Stoic tracks the ripple, not just the splash it leaves behind.
- Incidents: What shifted under the surface to set this off?
- Refactors: Which loops are we tightening and which are we breaking apart?
- Teams: What tensions are we easing, and what are we accidentally feeding?
Signal vs Noise
Clarity isn't quiet, it's sharp.
Cut the fluff. Skip the spotlight. Pay attention to what lands.
- Metrics: Are we measuring what matters or just watching numbers jump around?
- Debugging: What's setting this off, and what's just the noise it leaves behind?
- Meetings: Are we making anything better or just burning an hour to feel busy?
Confirmation Bias
You'll always find what you want.
The Stoic looks for what contradicts comfort.
- Incidents: If I'm wrong, what would I be missing right now?
- Hiring: Am I drawn to what I know, or what we need?
- Reviews: Am I checking for cracks or just nodding at cleverness?
Mental Time Travel
The Stoic rehearses adversity in advance.
Before you ship, visualize what breaks.
- Feature planning: "What will this look like postmortem?"
- Architecture: "If this breaks, what does it take with it?"
- Reviews: "What's the edge case I'm ignoring right now?"
II. Models of Action
How Stoics Move with Intention
"Waste no more time arguing what a good person should be. Be one." - Marcus Aurelius.
Action without clarity turns into noise.
These models steady your hand when pressure tells you to flinch.
OODA Loop
Observe. Orient. Decide. Act.
Don't just move fast, move from the ground up.
Panic blurs. Calm sharpens. That's how you see straight when it counts.
- Incidents: Don't chase the dashboard. Step back. Reframe what matters. "Did we get our bearings or just start swinging?"
- Leadership: Don't chase metrics. Step back. Ask what changed.
- Sprints: Start with reflection. Then aim. Then act like you mean it.
Eisenhower Matrix
Urgency makes noise. Meaning doesn't shout.
The Stoic builds around what matters before the pings steal the wheel.
- Planning: Block time that builds before firefighting starts.
- Burnout Recovery: Cut what clutters. Protect your margins like uptime.
- Mentoring: Don't just respond. Build rhythm. Growth moves slowly for a reason.
Barbell Strategy
Anchor where it holds.
Take swings where you can miss without bleeding.
The middle? That's where it all breaks down when stress comes calling.
- Architecture: Lock down the backend. Try new ideas in the UI where risk is cheap.
- Hiring: Pair battle-tested devs with curious minds who haven't learned the limits yet.
- Tech choices: Choose stable by default. Isolate the wildcards so they can't take you down with them.
Cross-Reference: sPlays well with Reversible vs Irreversible Decisions. When your core holds, you can afford to fail forward at the edges.
Tactical Retreat
Backing off isn't weakness. It's judgment.
When the signal fades, the Stoic doesn't swing harder.
They slow down. Scan the edges.
Figure out what's off before stepping back in.
- PR dragging? Archive it. Start clean.
- Head full of fog? Step away. Let motion clear the noise.
- Team energy off? Say it out loud. Reset the rhythm before you chase velocity.
Triage Protocol
Not all alerts are alarms.
Distinguish critical, ignorable, and contagious problems.
- During outages, ask: "What do we fix first?"
- Planning: What's urgent and compounding?
- Team health: Who's burning out silently?
III. Boundaries & Systems
How Stoics Reason About Risk and Responsibility
"When the stakes are highest, your character is your boundary."
Trust Boundaries
Every boundary is a permission.
The Stoic revalidates assumptions at the edges of code, of teams, of thought.
- PRs: "Where am I trusting the user or client implicitly?"
- Cross-team projects: "What expectations are unspoken?"
- Security: "Am I validating or just hoping?"
Incentives
Every API, every workflow nudges behavior.
If you don't shape the path, friction will.
- Error messages: Don't just name the failure, show what to do next.
- Code Style: Bake it into the tooling. Preach less, automate more.
- Team norms: Reward the boring brilliance of consistency. Not the adrenaline rush of a save.
Red Queen Effect
Just because you're moving doesn't mean you're getting anywhere.
The Stoic doesn't chase speed. They adapt with intention because entropy never clocks out.
- Security: Don't wait for a headline. Check what you trust, then recheck it.
- CI/CD: Trim the drag. One friction fix at a time.
- You: Don't coast. Stretch before the job stops fitting.
Scarcity vs Abundance
Scarcity hardens egos. It turns teams inward.
Abundance doesn't mean excess; it means trust.
The Stoic engineer gives credit freely and guards the space where good work can happen.
- Reviews: Look for the signal. Make the work stronger quietly, precisely.
- Leadership: Share the wins. Shield the team.
- Conflict: Ask before assuming. Lower the temperature first.
Murphy's Law / Parr's Law
Failure doesn't send a heads-up.
It hits when you're tired, rushed, or live on Friday.
The Stoic doesn't plan for luck. They build so the blast radius stays small.
- Deploys: Assume rollback. Make it simple, fast, and boring.
- Testing: Start where it's ugly. The clean paths won't surprise you.
- Product: Leave room to trip and land without breaking everything.
IV. Reflection & Correction
How Stoics Build What Endures
Peter Principle
Push too far, and people break like systems.
The Stoic doesn't climb by default. They earn height by reinforcing the base.
- Promotions: Title follows trust. Make sure the work is already there.
- Scaling: Don't ask if it runs. Ask what breaks when it doubles.
- Self-check: Are you growing roots or just getting taller?
Compounding Interest
Tiny changes add up. So does the mess you leave behind.
The Stoic doesn't chase spikes. They build rhythm, and let it pay off.
- PRs: Leave the code better than you found it. One clean-up at a time.
- Docs: Fix the gaps as you go. Future-you will thank you.
- Learning: Ten minutes of focus beats an hour of scattered noise.
Tragedy of the Commons
No one owns shared code until it breaks.
The Stoic sees the mess and steps in. They fix what needs fixing, then move on.
- Linting: Set the standard. Bake it into the workflow.
- Comments: Explain just enough so the next person doesn't guess.
- Meetings: Make the point. Capture the decision. Don't assume memory will.
Reversible vs Irreversible Decisions
Move fast when the cost of being wrong is low.
Slow down when the downside lingers.
The Stoic knows the difference and acts like it matters.
- Stack choice? Breathe. Then decide.
- Button colors? Just ship.
- Hiring? If you're unsure, wait.
- Firing? Don't flinch, but don't rush.
How to Practice
- Daily: Ask, "What lens am I missing right now?"
- Weekly: What helped? What didn't? What did I ignore?
- In PRs: Mark the mindset: // TrustBoundary, // PremortemCheck, // Type1Decision
- Journaling Prompt: Where did I move from clarity? Where did chaos take the wheel?
Further Reading
Stoic Foundations
Meditations - Marcus Aurelius
Wrote to himself, not for us. Which is why it lands harder. Quiet, direct, no wasted breath.
Discourses - Epictetus
Says less than most. Means more. Born into chains. Taught freedom anyway.
Letters from a Stoic - Seneca
Half comfort, half blade. If you read him right, you walk away changed.
Mental Models
The Great Mental Models - Farnam Street
Not all of it sticks. But the ones that do change how you see everything.
Poor Charlie's Almanack - Charlie Munger
Blunt. Long-winded. Brilliant. Read it slowly, or don't read it at all.
Thinking in Systems - Donella Meadows
More useful than clean code. Helps you see what's coming before it hits.
Reflection
The Stoic doesn't just act, they move with reason. They don't just build, they build on what holds, even when everything else buckles
This isn't just a reference. It's a way to think when thinking gets hard. A way to move when pressure closes in. A way to lead when the room goes quiet and all eyes turn your way.
Let it shape your rhythm. Sharpen your edge. Hold your calm.