Do you remember MapReduce? That distributed computing pattern that powered early Google and Hadoop? “Mapping” a lot of tasks to some compute clusters, then “reducing” the results? Well, I’ve been experimenting with applying the same concept to AI tasks using Claude Code, and the results have been surprisingly powerful. This is already being used to generate RAGs, but it’s a lot more fun to try it locally in your own documents.

The problem: AI Tasks don’t scale linearly.

When you have a large set of tasks, throwing a huge context or getting a huge ToDo list as a tool call, is not useful, after a while the context window “limits” itself and starts to be less effective. This leads to us having long processing time with no intermediate results.

It also makes it hard to debug when things go wrong.

Enter AI ‘Map Reduce’.

The concept is simple: use Claude Code’s headless -p flag in a parallel manner to solve small tasks, and then have some process to summarize or have another process pick get the summaries.

Here’s the pattern,

# Map phase: Process each chunk
for item in dataset; do
  claude -p "Analyze this item and output JSON: $item" \
  > "output_${item}.json" &
done
wait

# Reduce:
jq [...]
# or 
claude -p "Aggregate these JSON files into a summary" \
--input "output_*.json" > final_result.json

Note that you can reduce with LLMs or with deterministic methods, whetever you are trying to do, I personally recommend deterministic methods not to add more randomness into the process.

Example use case:

Analyze my blog posts.

Instead of asking claude to go and do a bunch of web calls to analyze my code, I chunked it to several processes and then “reduced them”

#!/bin/bash
mkdir -p analysis_output

for post in content/blog/*.md; do
  echo "Analyzing $(basename "$post")..."
  claude -p "Analyze this blog post and extract key metrics as JSON:

$(cat "$post")

Required Output Format (JSON only):
{
  \"title\": \"\",
  \"word_count\": 0,
  \"reading_time_minutes\": 0,
  \"main_topics\": [],
  \"tone\": \"technical|personal|educational\",
  \"complexity_score\": 1-10,
  \"key_insights\": [],
  \"technologies_mentioned\": [],
  \"actionable_takeaways\": ["",""]
}

Be precise and consistent with the JSON structure." \
  > "analysis_output/$(basename "$post" .md).json" &
    
    # Prevent overwhelming the API
    if (( $(jobs -r | wc -l) >= 3 )); then
        wait
    fi
done
wait

Then, for each of my posts, I get something like this:

{
  "title": "AI Map Reduce",
  "word_count": 387,
  "reading_time_minutes": 2,
  "main_topics": ["AI task parallelization", "Map Reduce pattern", "Claude Code CLI", "Performance optimization"],
  "tone": "technical",
  "complexity_score": 6,
  "key_insights": [
    "AI tasks don't scale linearly with large contexts or todolists",
    "Parallel processing with Claude Code's headless flag can solve scalability issues",
    "Breaking large AI tasks into smaller chunks provides better debugging and intermediate results",
    "Deterministic reduction methods are preferable to LLM-based reduction to avoid added randomness"
  ],
  "technologies_mentioned": ["Map Reduce", "Hadoop", "Claude Code", "bash", "JSON", "MCP tools"],
  "actionable_takeaways": [
    "Use Claude Code's -p flag with parallel processing for large dataset analysis",
    "Implement job control (limiting concurrent processes) to prevent API overwhelming",
    "Structure outputs as JSON for easier aggregation in the reduce phase",
    "Create intermediate output files for better debugging and progress tracking"
  ]
}

This way, I can check what are my most complex blog posts, categorize them, or add more relevant tags to all of them!

Now, as it is obvious, AIs are really bad at counting words, or doing numerical things, but in this case… I don’t care too much! I think these techniques are better for things where I need a “good enough” anwser.

As a practical example, this makes it really awesome to get a summary of all the takeaways of my blogs:

for file in *.json; do
  jq -r --arg filename "$file" '
    "[\(.title)](blog/\($filename))",
    (.actionable_takeaways[] | "- \(.)")
  ' "$file"
  printf "\n"
done

(See them below the closing!)

Experiment with AI Map Reduce and let me know what you think! My next steps would be trying this with something like LangChain and make it more like a state machine. Let me know here or in the comments what you think, it might not be novel, but it’s pretty fun.

My “summarized takeaways” from all my blogposts:

Alternate data streams, the dark side of NTFS.

• Use ‘dir /R’ command to detect alternate data streams in directories
• Check file properties to identify size discrepancies indicating ADS presence
• Be aware that ADS cannot be disabled on NTFS systems
• Understand that moving files to FAT32 filesystems removes ADS

Affinity Designer Google Display Ads Template

• Download the .aftemplate file for ready-made Google Display Ad templates
• Ensure X and Y positions are integers (not decimals) when exporting to avoid size issues

AI Map Reduce

• Use Claude Code’s -p flag with parallel processing for large dataset analysis
• Implement job control (limiting concurrent processes) to prevent API overwhelming
• Structure outputs as JSON for easier aggregation in the reduce phase
• Create intermediate output files for better debugging and progress tracking

Apollo: A history of software design.

• Explore the Apollo 11 GitHub repository for historical software engineering examples
• Try the VirtualAGC simulator to understand Apollo computer systems
• Study fault-tolerant programming principles from historical examples
• Consider how modern tools compare to manual precision of early software development

Part 1: How breaking computers taught me to build them.

• Don’t be afraid to break things while learning - it teaches you how systems work
• Join communities and forums to accelerate your learning
• Try different operating systems and configurations to understand computing fundamentals
• Use creative projects (like game stores) to make learning programming more engaging

Part 2: Beyond Code, The Power of Communication

• Make presentations fun with personal style and animations
• Think about your audience and embody their mindset
• Practice presentations with real people, not mirrors
• Use power poses before presenting to boost confidence
• Invest in developing social and communication skills

Part 3: No Pay, No Work; Early Career Lessons

• Establish clear payment expectations and boundaries
• Don’t work for free regardless of guilt trips about loyalty
• Value early career opportunities while maintaining professional standards
• Learn from technical challenges even in chaotic environments

Part 4: Finding pride in shipping real features

• Apply broadly to job opportunities to maximize chances of landing internships
• Seek positions where you can see direct impact on end users
• Value mentorship opportunities and learning sessions with senior developers
• Embrace working with legacy code as a learning opportunity
• Balance academic learning with practical experience for comprehensive skill development

Part 5: Many Bosses, The Reality of Running Your Own Company

• Validate business ideas manually before building expensive software
• Set clear expectations with clients, especially for marketing services
• Don’t try to be both manager and individual contributor without clear boundaries
• Test concepts on existing platforms before building custom solutions
• Ensure supplier reliability before selling products you can’t control
• Pre-sell with landing pages to measure market interest

Part 6: How OneNote Storage works, in-depth

• When designing sync systems, consider differential updates over full file replacement for better performance
• Implement sophisticated conflict resolution algorithms for real-time collaborative editing
• Plan for data residency and compliance requirements early in system architecture
• Approach legacy codebases with respect and seek to understand the historical context behind design decisions
• Balance backward compatibility with modern protocol improvements during system transitions

Part 7: Office Migration from Source Depot to Git, or how I learned to love DevEx.

• Use hub-and-spoke communication model with designated champions for large teams
• Communicate important information at least 3 times through different mediums
• Build training environments that map old workflows to new ones
• Create authentic video libraries showing real developers solving real problems
• Always have a rollback strategy and ‘red button’ for leadership
• Measure satisfaction alongside technical metrics
• Invest heavily in proving system equivalence before switching
• Plan for much more communication overhead than initially estimated

Why client shaming is hurting the software industry

• Ask clarifying questions to understand client requirements rather than dismissing them
• Focus on solving the underlying problem the client is trying to address
• Educate clients about technical constraints and alternatives in a respectful manner
• Position yourself as a solution provider rather than just a technical implementer

How to sleep at night having a cloud service: common Architecture Do’s

• Implement Infrastructure as Code to track and revert infrastructure changes
• Set up CI/CD to catch compilation and test failures before deployment
• Add correlation IDs to all requests for easier debugging across services
• Implement centralized logging to search across all machines from one place
• Configure monitoring agents to check service health and alert on issues
• Set up autoscaling to handle traffic spikes automatically
• Consider blue-green deployments for zero-downtime updates

How to copy all your repositories without node_modules with rsync.

• Use ‘rsync -av –exclude node_modules source destination’ to copy repositories without node_modules
• Apply gitignore rules to rsync with ‘–filter=":- .gitignore"’ flag

Developer productivity is 99% perception

• Be mindful of how you communicate about systems and processes to new team members
• Regularly survey developers and acknowledge their feedback
• Announce improvements to boost morale, but ensure actual improvements follow
• Focus on perception as a key component of developer productivity frameworks
• Avoid cynical language when discussing development tools and processes

How my manager tricked us team into doing things: The Experiment Framework

• Use the experiment framework: set hypothesis, rules, definite duration, and team voting
• Don’t mandate changes - experiment with them instead
• Give teams control over keeping, stopping, or tweaking processes
• Frame improvements as temporary experiments to reduce resistance

Mexico City: my travel recommendations.

• Visit Bellas Artes and walk through Calle Madero to Zocalo on day 1
• Book Hotel de Mexico for rooftop dining with Zocalo views
• Start day 2 with breakfast at Catamundi in Polanco
• Experience authentic tacos at Taqueria Selene for street food
• Hike to Chapultepec Castle for historical perspective
• Book a guided tour for Teotihuacan pyramids visit
• Allow full days for each recommended itinerary

Mexico uses asymmetric encryption for university diplomas and taxes.

• Consider digital identity systems as alternatives to social security numbers
• Implement automated tax calculation systems based on digitally signed transactions
• Use government-issued cryptographic keys for official document verification
• Leverage digital signatures to streamline bureaucratic processes

How I got my internship at microsoft?

• Join competitive programming contests (IOI, TopCoder, ACM ICPC)
• Implement each important algorithm type at least 3 times
• Practice mock interviews with friends
• Use specific resources: Cracking the Coding Interview, Gayle McDowell’s videos, Interview Cake
• Work on cool projects or get internship experience before applying
• Pay attention to class material and explore concepts deeply through coding
• Focus on communication skills during HR interviews

The broken Microsoft Pact: Layoffs and Performance Management

• Maintain 6+ month emergency fund for unexpected job loss
• Focus on building external networks and transferable skills
• Negotiate compensation harder without stability premium justification
• Keep resume updated and maintain relationships outside current company
• Understand new employment reality when making career decisions

How cynicism can grow or destroy software organizations.

• Empathize and validate concerns to acknowledge the cynic’s emotional state
• Use effective communication techniques like mirroring to understand root problems
• Work on team dynamics through team-building activities and improving overall morale
• Ask clarifying questions to dig deeper into specific concerns
• Address grassroots problems rather than just surface-level symptoms

Passive agressive CC’ing

• Avoid CCing important people who don’t need to be involved in technical issues
• Ask for technical opinions directly rather than through hierarchy manipulation
• Only involve management when the issue genuinely requires their attention
• Focus on professional problem-solving rather than power plays

Programs that have saved me 100+ hours by automating repetitive tasks

• Use PhotoBulk for batch image processing (resize, watermark, rename)
• Learn regex for fast text transformations in editors
• Set up direct FTP/database connections for urgent server changes
• Use smart launchers (Alfred/Spotlight) for quick file access and calculations
• Implement rule-based file organization to maintain clean workspace

Programs that have saved HackerNews 100+ hours by automating repetitive tasks

• Learn AutoHotKey or BetterTouchTool to automate repetitive keyboard/mouse tasks
• Master basic Unix utilities (grep, awk, sed) for efficient text processing
• Use package managers instead of manual software downloads
• Implement window management tools for better screen organization
• Consider the time investment vs. time saved before automating (XKCD rule of thumb)

Please ignore and remove your wp-config from GitHub

• Add wp-config.php to .gitignore before committing
• Use environment variables or separate config files for sensitive data
• Renew WordPress security keys and salts if exposed
• Monitor search engine exposure of your site
• Configure database to only accept local connections
• Be aware that deleted files remain in git history

What I learned after three internships at Microsoft.

• Identify what type of work makes you passionate (creation, problem-solving, or optimization)
• Read Hacker News and Reddit Programming daily for 10-20 minutes to stay current
• Maintain work-life balance by operating at 90% capacity rather than burning out
• Keep a detailed journal of accomplishments and communicate progress to your team
• Focus on over-communication rather than under-communication with colleagues

(If you are still here, thanks for reading :D)