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Arbythecoder
Arbythecoder

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Why Does Your Code Work on Your Laptop But Breaks in Production? πŸ’»βž‘οΈπŸ’₯

The classic developer nightmare that birthed the DevOps movement


We've All Been Here πŸ˜…

# Your laptop
$ npm test
βœ… All tests passing
$ npm start  
βœ… Server running perfectly

# Production server  
$ npm start
πŸ’₯ EVERYTHING IS ON FIRE πŸ”₯
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Sound familiar? Let's dive into why this happens and how to fix it.

The Environment Gap Problem

Your development environment is like a perfectly controlled lab. Production? That's the wild west.

What's Actually Different?

Development:

{
  "node": "16.14.2",
  "os": "Windows 11", 
  "memory": "16GB",
  "database": "local",
  "env_vars": "all_present",
  "mode": "debug"
}
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Production:

{
  "node": "18.12.1", // ⚠️ Version mismatch!
  "os": "Ubuntu 20.04",
  "memory": "2GB", // 😱 Resource constraint
  "database": "remote_with_limits",
  "env_vars": "missing_secrets", // πŸ’€ Classic
  "mode": "production"
}
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Real Horror Stories From the Trenches

The Missing Environment Variable πŸ”‘

// Works locally
const secret = process.env.JWT_SECRET; // "supersecretkey123"

// Production
const secret = process.env.JWT_SECRET; // undefined πŸ’€
// Result: Authentication completely broken
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The Database Engine Mixup πŸ—ƒοΈ

-- Local PostgreSQL: Works fine
SELECT * FROM users LIMIT 10;

-- Production MySQL: Syntax error
-- Same query, different engine = chaos
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The File Path Disaster πŸ“

// Local Windows path
const uploadPath = 'C:\\Users\\dev\\uploads\\';

// Production Linux: 
// Error: ENOENT: no such file or directory
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The Jollof Rice Analogy 🍚

Imagine you're a jollof rice master at home. Perfect every time! Then you cook for a wedding with:

  • Different stove (gas vs electric)
  • Different rice brand
  • Different pot size
  • Missing spices
  • Time pressure

Same recipe, different environment = disappointing results.

That's your code in production.

Warning Signs You're in Danger ⚠️

  • [ ] Different language/framework versions locally vs prod
  • [ ] Manual file copying for deployment
  • [ ] Secrets only exist in your .env file
  • [ ] Never tested on production OS
  • [ ] Different database engines/versions
  • [ ] Deploy with prayers πŸ™
  • [ ] New devs take days to setup locally

3+ checked? You're living dangerously!

The DevOps Solution Preview πŸ› οΈ

The answer? Environment standardization through:

  • Docker: Package everything consistently
  • Infrastructure as Code: Standardize server setup
  • CI/CD: Automated, repeatable deployments
  • Configuration Management: Same settings everywhere

We'll dive deep into each of these in upcoming posts.

Quick Wins You Can Implement Today βœ…

  1. Document your local environment
   node --version > versions.txt
   npm list --depth=0 >> versions.txt
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  1. Use exact versions in package.json
   {
     "node": "16.14.2", // Not "^16.0.0"
     "dependencies": {
       "express": "4.18.1" // Not "^4.18.1"  
     }
   }
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  1. Create environment checklists
    • OS version
    • Runtime versions
    • Database setup
    • Required environment variables

Your Turn! πŸ’¬

Share your worst "works on my machine" story in the comments!

What broke? How long did debugging take? What did you learn?

Let's learn from each other's pain! πŸ˜„


Follow me for more DevOps fundamentals that make sense!

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Top comments (13)

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junaid_dev profile image
Junaid β€’

πŸ˜ƒ Same.
Even I double check everything before production, but some errors will got in anyway
Output :

Ok
Ok
Error !
Server is running at abujuni.dev
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Me : Error, anyway server is running.

When I open browser and went to the page then BOOM πŸ’₯ , Random unknown error made server crash.

After digging the code changing lot, I remember that β€œIs all dependencies are added” , as always there is 1 dependency is MISSING.

After adding that all will be fine.
By the way I am talking about Flask(python) and react(npm)

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arbythecoder profile image
Arbythecoder β€’

Thanks for sharing your experience, Junaid! It’s so frustrating when a missing dependency causes chaos. It sounds like you handled it well in the end. Keep double-checkingβ€”those little things can sneak up on us!

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nevodavid profile image
Nevo David β€’

been there way too many times, tbh - does any one of those fixes actually stop all the pain or is it always a moving target?

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arbythecoder profile image
Arbythecoder β€’

Hey Nevo! I get thatβ€”it really can feel like a never-ending battle. Even with fixes, our environments are always shifting. Let’s keep sharing our experiences and supporting each other through these challenges. What do you think?

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mickeycodess profile image
Michael Obasoro β€’

Fairs, that's one of the best analogies I've seen till date πŸ˜‚

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jess profile image
Jess Lee β€’

Haha came here to leave the same comment!

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mickeycodess profile image
Michael Obasoro β€’

🀣🀣

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arbythecoder profile image
Arbythecoder β€’

Thanks, Michael! I'm glad you liked the analogy! It really does capture the chaos we often face. If you have any other analogies, feel free to share; I’d love to hear them!

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dotallio profile image
Dotallio β€’

Definitely been bitten by a missing env variable that only showed up in prod and took hours to trace down. What's your favorite way to catch these before deploy?

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arbythecoder profile image
Arbythecoder β€’

Great question, Dotallio! I’ve found that using a staging environment helps catch those sneaky issues before deployment. What strategies do you use to prevent surprises?

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maglagla profile image
Markus Glagla β€’

A software development classic, thank you Arby! I would add automated tests and a dedicated test/integration environment to the list.

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doozieakshay profile image
Akshay Joshi β€’

This is a common scenario when the development environment (Windows) differs from the default hosting environment, which is typically Linux.

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arbythecoder profile image
Arbythecoder β€’

Absolutely, Akshay! The difference between local and production environments can be a real challenge. It’s a good reminder for all of us to stay vigilant. Thanks for your insight!

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