Jatin Jain Saraf · JJS InsightsArchitect of SupraScanWhat breaks in production databases, and how to fix it.
Notes from running PostgreSQL in production. I'm the architect of SupraScan, a blockchain indexer running 500–1,000 TPS on a database that grew to 10 TB before I cut it to 2.7 TB.
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Bloom Filter, Reservoir Sampling, HyperLogLog: Three Probabilistic Answers to Three Different Questions
All three trade exactness for memory, which is why they get mixed up. A Bloom filter answers "have I seen this wallet?", a reservoir answers "give me a fair sample of the stream", and HyperLogLog answers "how many distinct wallets?". Pick the wrong one and you don't get a slightly worse answer. You get a confident answer to a question you didn't ask.
Your Node.js App Never Imports zlib. It Might Still Be Vulnerable to a Brotli RCE
Node.js patched CVE-2026-111497, a High-severity Brotli decoder flaw, on October 21, 2026. I traced the built-in fetch() through Undici to show how a response reaches that decoder even when your code never imports zlib, and wrote up the checklist for verifying what production actually runs.
You Might Not Need a Queue Service: Postgres SKIP LOCKED as a Job Queue
Before adding Redis, BullMQ, or SQS just to distribute background work, look at the database you already run. PostgreSQL's FOR UPDATE SKIP LOCKED lets multiple workers claim different jobs concurrently. Learn how to handle expired leases, retries, MVCC bloat, and notification-based wake-ups, and when a dedicated queue is the better choice.
How a B-Tree Really Reads, Inserts, Updates and Deletes (and Where It Fails a Blockchain Indexer)
A B-tree is cheap to search and expensive to keep sorted. Here’s what reads, inserts, updates and deletes actually do inside one in PostgreSQL, and how that should decide the index on every table of a blockchain indexer, from wallet history to balances to NFTs.
Turning Your Blockchain Indexer Into a Paid API Without Slowing Down Your Explorer
Turning blockchain indexer data into a paid API is easy. Keeping API traffic from slowing your explorer or ingestion is the hard part. This post presents a production architecture using replica pools, read models, finality-aware caching, Redis quotas and per-plan bulkheads.
Your Postgres Indexes Can Break Without a Single Line of Code Changing
You bumped the base image or rebuilt a replica on a newer OS. No deploy, no migration. Then a unique index lets in a duplicate and an indexed lookup misses a row you can see. Here's how collation drift breaks B-tree indexes, how to prove it with amcheck, and the fix order that doesn't silence the only alarm.
Your UUID Primary Keys Are Quietly Taxing Every Insert
Random UUIDv4 keys look harmless until the table grows. Every insert lands on a random B-tree leaf page, the index outgrows the buffer cache, pages split half-empty, and full-page writes inflate WAL after every checkpoint. A 10M-row PostgreSQL 18 benchmark shows the cost, and why native uuidv7() recovers almost all of it without giving up distributed ID generation.
The TOAST Tax: How Unbounded JSONB Arrays Cost My Blockchain Indexer 5TB
Our PostgreSQL blockchain indexer's TOAST table grew past 5TB because unbounded JSONB arrays kept getting bigger. Here's what TOAST was costing us, how to measure it, and how we moved hot JSONB fields into normal columns without taking the indexer offline.
Every Postgres Write Triggers Five Background Processes. Here's What Each One Actually Does.
An UPDATE returns in two milliseconds, but underneath, Postgres just ran WAL logging, checkpoint bookkeeping, wait-event tracking, vacuum, and ANALYZE to make that write durable, recoverable, and still fast to plan. Here's what each of those five processes actually does, and which one is usually behind the latency spike that has no slow query in sight.
Browse all 61 articles
- Bloom Filter, Reservoir Sampling, HyperLogLog: Three Probabilistic Answers to Three Different Questions
- Your Node.js App Never Imports zlib. It Might Still Be Vulnerable to a Brotli RCE
- You Might Not Need a Queue Service: Postgres SKIP LOCKED as a Job Queue
- How a B-Tree Really Reads, Inserts, Updates and Deletes (and Where It Fails a Blockchain Indexer)
- Turning Your Blockchain Indexer Into a Paid API Without Slowing Down Your Explorer
- Your Postgres Indexes Can Break Without a Single Line of Code Changing
- Your UUID Primary Keys Are Quietly Taxing Every Insert
- The TOAST Tax: How Unbounded JSONB Arrays Cost My Blockchain Indexer 5TB
- Every Postgres Write Triggers Five Background Processes. Here's What Each One Actually Does.
- Your ORM Isn't Lying to You. It's Just Not Telling You Everything.
- The Dual-Write Problem: Why "Update the DB, Then Publish an Event" Is Broken
- Elasticsearch Isn't Dead. You Probably Don't Need It
- Why Your Docker Image Is 3GB and Nobody Noticed Until the Deploy Timed Out
- Why Postgres and Cassandra Made Opposite Bets on Storage Engines
- The Codebase You Sit In Rubs Off On You
- PostgreSQL's Async I/O Engine: Why Your Sequential Scans Just Got 2-3x Faster
- Vector Search in Postgres: What pgvector's Indexes Actually Cost You
- The Three Layers of Failure Isolation: Timeouts, Circuit Breakers, and Load Shedding
- Connection Pooling in the Serverless Era: Five Failure Modes
- PostgreSQL 19 vs. 18: What Actually Changed, Feature by Feature
- Idempotency Keys: How to Make Retries Safe in Distributed Systems
- How the LRU Cache Actually Works and Why Redis, Browsers, and Postgres All Approximate It
- Why a Single ALTER TABLE Can Take Down Your Whole Database
- What the PostgreSQL Server Is Actually Doing
- Competition Is Inevitable. Cruelty Is Optional
- Transactions and ACID in Practice: What Every Backend Developer Must Know
- When Judgment Becomes the Bottleneck
- Mastering PostgreSQL: 5 Essential Tips for Performance Optimization
- Redis HyperLogLog: Counting Millions of Unique Users with Just 12KB of Memory
- Microservices Don't Collapse Because They're "Too Complex"
- Ownership Mindset: Thinking Beyond Assigned Tasks
- The React Server Components Vulnerability That Shocked the Web Ecosystem
- A Redis Command That Quietly Solves One of the Hardest Problems in High-Concurrency Systems
- The Responsibility Behind Honest Feedback
- The Impact of Words in Professional & Personal Spaces
- Professionalism Isn't Rigidity — It's Responsibility
- Your Blockchain Indexer Is Fine — Until It Isn’t
- Database Efficiency 101: Understanding Bloat, Vacuum, and the Power of pg_repack
- The Power of LATERAL Joins: Turning SQL into a “ForEach” Loop
- PostgreSQL 18: A Paradigm Shift for Modern Data Workloads
- Cloud‑to‑Cloud Database Migration: A Practical Guide for Large PostgreSQL Systems
- The Hidden Architecture Behind Six Degrees of Separation
- The Complete Developer’s Guide to Indexing Assets on Supra & Aptos (Coins, FAs, NFTs)
- The PostgreSQL Elephant in the Room: A Deep Dive Into the Architecture That Powers Giants
- From Lag to Leading: A Deep Dive into Fixing a 2-Hour PostgreSQL Replication Lag
- Taming PostgreSQL Replication Lag in Real-Time Blockchain Indexers
- Understanding Source Code vs Bytecode in Move-Based Blockchains
- Demystifying API Gateway Patterns: Design Choices, Real-World Use Cases & When to Use What
- Handling Large Datasets & High-Traffic Queries: Optimizing Pagination, Sorting & Filtering
- The Ultimate Git Command Guide: Streamline Your Development Workflow
- Strings in JavaScript: An In-Depth Guide
- Choosing Between Type and Interface in TypeScript: A Detailed Guide
- Unveiling the Power of Descriptive Naming Conventions in JavaScript
- Navigating Your Career: Deciding Which Skills to Develop at Each Stage
- What's New in Next.js 14
- Linux Terminal Basics Commands:
- JavaScript ES6 Coding Conventions
- 40 Best Practices for Writing Clean JavaScript, React, and Node.js Code
- Branching Guidelines and Conventions
- Sequelize using Postgres dialect
- Clustering In NodeJs
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