Latest Insights & Updates

Discover quantitative strategies, market updates, and news from HarvestGroup360.

Risk Management
The Square Root of Twelve Is an Assumption

A monthly Sharpe ratio of 0.1939 annualises to 0.67 or to 0.49, depending on a multiplier nobody questions.

Mariusz Skobel
September 16, 2026
Quantitative Models
The Average Return Is Not a Return Anybody Received

Four periods of plus fifty and minus forty per cent average out to a gain of five per cent, and the account is down nineteen.

HarvestGroup360
September 15, 2026
Quantitative Research
The Sharpe Ratio of a Residual Is Always Zero

Eighty-one per cent of this strategy's return is three factors anyone can buy, and the obvious way to measure what is left returns zero every time.

Mariusz Skobel
September 14, 2026
Market Structure
Forty Positions Is Not Forty Bets

A book of forty names with an average pairwise correlation of 0.486 holds about three and a half independent bets.

HarvestGroup360
September 13, 2026
Risk Management
Twelve Defensible Pipelines, One Published Number

Three cleaning decisions nobody argued about produce twelve versions of the same backtest, between an annualised Sharpe of 0.49 and 0.71.

Mariusz Skobel
September 12, 2026
Quantitative Research
Every Backtest Has a Start Date Somebody Chose

The same strategy on the same thousand days: an annualised Sharpe of -0.77 over everything, +0.57 starting twenty-three months in.

HarvestGroup360
September 11, 2026
Data Engineering
The File Did Not Change. The Answer Did.

A Sharpe of 0.99 deflates to 1.0000 against 50 trials and 0.0046 against 500. The input file is identical in both runs.

Mariusz Skobel
September 9, 2026
Risk Management
In a Backtest, Every Stop Fills

Five halts took 0.10% of the month and carried 6.87% of the money. The rule traded hardest where it could not trade.

HarvestGroup360
September 7, 2026
Market Structure
The Biggest Trade of the Day Was Not a Trade

Two prints out of 391 carried 14% of the volume. The benchmark that includes them sits 8.2 bps away from the market.

Mariusz Skobel
September 6, 2026
Data Engineering
A Thousand Rows, Two Hundred Observations

Overlapping labels inflate every t-statistic computed on them. A t of 2.1 is really 0.94, and the overlap did that.

Mariusz Skobel
September 5, 2026
Risk Management
AI Made Strategies Cheap. Evidence Did Not Get Cheaper.

Five thousand worthless variants produce a Sharpe of 1.65 from nothing. The market did not change — the trial count did.

HarvestGroup360
September 4, 2026
Market Structure
Your Volume Profile Already Knows How the Year Ends

Everyone removes the shape of the trading day. Almost nobody checks whether the curve they removed it with had happened yet.

Mariusz Skobel
September 2, 2026
Data Engineering
Your Backtest Knew the Price Before Your Machine Did

A venue timestamp is not an arrival. Measuring the gap, and what keying research on the venue stamp quietly buys.

Mariusz Skobel
September 1, 2026
Open Source & Engineering
What We Refuse to Build, and the One Refusal We Reversed

Five things the library will not do, the reason written next to each — and the one we overturned when the objection turned out to be testable.

HarvestGroup360
August 31, 2026
Microstructure
Your Price File Is Either Prints or Arithmetic

A venue only accepts multiples of a tick. One pass over the file tells you whether those prices could ever have traded.

Rizky Setya Maulana
August 30, 2026
Market Structure
The Year Everyone Calls 252 Sessions Long Was 251

261 weekdays, ten closures, two half-days. One date read the wrong way gives exactly 252 — the number nobody checks.

Mariusz Skobel
August 29, 2026
Quantitative Research
Every Name on Today's List Is a Name That Survived

Four years back, a today-list gets 40 of 100 index names wrong: 20 dropped, 20 held before they joined. The two do not cancel.

Rizky Setya Maulana
August 27, 2026
Data Engineering
Joining a Daily Value to an Intraday Grid Without Reading It Early

A daily close is not knowable at nine in the morning. On back-to-back periods the label join is wrong at every point, not most.

Mariusz Skobel
August 26, 2026
Infrastructure & Latency
Is Python's Decimal Slow? We Measured Before Rewriting

Exact decimal arithmetic cost 3.1x a float loop. The trailing window, which nobody asked about, cost 44x.

Rizky Setya Maulana
August 25, 2026
Guide
How to Build and Validate a Point-in-Time Symbol Map

The same universe, two reference files. One resolves 15 rows; the other mis-attributes 5 and drops 3 without a warning.

Mariusz Skobel
August 24, 2026
Quantitative Research
The Deflated Sharpe Ratio: When a Backtest Is Just the Best of Many

Two hundred strategies made of random numbers. The best scores 2.43 annualised and passes every standard check.

Rizky Setya Maulana
August 22, 2026
Data Engineering
How to Audit a Pipeline for Look-Ahead Bias

Nine checks, one per stage. If a check removes nothing, that is the finding rather than a pass.

Mariusz Skobel
August 21, 2026
Data Engineering
Look-Ahead Bias in As-Of Joins

A one-minute bar labelled 09:30 contains everything that traded until 09:31. Join it on the label and you import a minute of the future.

Rizky Setya Maulana
August 19, 2026
Data Engineering
The VWAP Benchmark That Flatters You

A public VWAP contains the trades you just made. The same buy scores -92 bps with its own prints in the benchmark and -1000 bps without.

Mariusz Skobel
August 16, 2026
Data Engineering
Trade Classification

Most tapes never say who crossed the spread. The tick rule, the quote rule and Lee-Ready recover it — and are wrong 15 to 25% of the time.

Rizky Setya Maulana
August 13, 2026
Data Engineering
Split-Adjusted Prices

Splits, dividends and futures rolls put returns in your data that never happened. What back-adjustment fixes, and the two conventions for doing it.

Rizky Setya Maulana
August 12, 2026
Data Engineering
Trading Sessions and Time Zones

Daylight saving, sessions that cross midnight and trading-day attribution — three silent bugs in market-hours filtering, and how to avoid them.

Mariusz Skobel
August 10, 2026
Guide
Market Data Normalization: A Practical Guide

The full path from a raw exchange feed to research-ready data: schemas, deduplication, quality checks, bar sampling, sessions and storage.

HarvestGroup360 Engineering Team
August 8, 2026
Quantitative Research
The Overfitting Trap: Why 99% Backtest Accuracy Should Scare You

Markets invert ML instincts: stellar accuracy is a diagnosis, not a triumph. Where leakage hides and the validation stack that catches it.

Rizky Setya Maulana
August 7, 2026
Infrastructure & Latency
What HFT Infrastructure Actually Looks Like

Colocation, feed handlers, kernel bypass, pre-trade risk and clock discipline — the honest, layer-by-layer tour of the path of an order.

Mariusz Skobel
August 6, 2026
Open Source & Engineering
market-data-normalizer 1.0 Is Here

Our open-source data library reaches its first stable release: composable pipelines, NDJSON I/O and a zero-dependency CLI for research-ready bars.

HarvestGroup360 Engineering Team
August 4, 2026
Open Source & Data
The Hidden Cost of Dirty Market Data

Discover the three silent killers of algorithmic trading backtests: bid-ask bounce, missing bars, and clock drift. See how market-data-normalizer v0.9.0 fixes them.

HarvestGroup360 Engineering Team
August 3, 2026
Architecture & Technology
Python vs C++ in Quant Finance

Discover the critical architectural separation in quantitative finance: why Python dominates research while C++ remains essential for low-latency execution.

Mariusz Skobel
August 2, 2026
Infrastructure & Latency
The True Cost of Latency

Discover why a 1-millisecond delay in order routing leads to adverse selection and how institutional infrastructure solves it.

Mariusz Skobel
July 31, 2026
Open Source & Engineering
Open-Sourcing market-data-normalizer v0.4.0

Every quant has been burned by a bad tick. We're releasing robust outlier detection, gap filling, and volume-weighted resampling to protect your backtests.

HarvestGroup360 Engineering Team
July 30, 2026
Quantitative Research
Microstructure Feature Engineering

Why training ML models on daily close prices destroys critical market signals, and the reality of working with L3 order book data.

Rizky Setya Maulana
July 29, 2026
AI & NLP
Out-of-the-box NLP APIs vs. Bare-Metal Micro-Transformers

Why standard NLP APIs like ChatGPT and BERT fail in high-frequency trading, and why bare-metal micro-transformers are the only solution for latency.

Rizky Setya Maulana
July 27, 2026
Company Culture July 26, 2026
Culture & Engineering

Bridging the critical gap between high-level data science and ultra-low latency systems engineering.

Read More →
Company News July 23, 2026
Building Trust in Institutional Trading

Why transparency, uptime reliability, and community feedback are the cornerstones of our infrastructure.

Read More →
NLP & Sentiment July 23, 2026
From Standard NLP to Financial Data

How the transition to chaotic market data fundamentally changes sentiment modeling.

Read More →
Quantitative Models July 21, 2026
Deep Learning in LOB Imbalance

How neural networks extract high-probability directional signals from Level II market data.

Read More →
FinTech Infrastructure July 19, 2026
FPGA in Ultra-Low Latency Trading

How hardware acceleration is revolutionizing tick data processing by pushing algorithmic logic to the silicon level.

Read More →
Engineering & API July 18, 2026
The Anatomy of an HFT API

Exploring the architectural requirements of Tier-1 FIX pipelines and the true cost of latency.

Read More →
Quantitative Finance July 17, 2026
Machine Learning in Quantitative Finance

How advanced ML architectures are replacing traditional statistical models in Tier-1 operations.

Read More →
FinTech & Business July 16, 2026
The Future of Market Intelligence

How HarvestGroup360 is democratizing access to Tier-1 analytical data feeds.

Read More →
Machine Learning July 15, 2026
Deep Reinforcement Learning in Market Making

How neural networks are replacing classic analytical models to dynamically manage inventory risk.

Read More →
Security & Infrastructure July 14, 2026
Building Enterprise-Grade Fail-Safes

Lessons learned from a Tier-1 security audit: How to protect client capital from black-swan events.

Read More →
Quantitative Strategy July 13, 2026
The Evolution of Statistical Arbitrage

How machine learning and ultra-low latency infrastructure have fundamentally transformed classic pair trading.

Read More →
Risk Management July 01, 2026
Real-Time Risk Engines: Pre-Trade Validation

Why algorithms cannot be trusted blindly, and how dynamic position sizing prevents catastrophic drawdowns.

Read More →
Security & Infrastructure June 20, 2026
Zero-Trust Architecture in Algorithmic Trading

How to protect API pipelines, dynamically encrypt exchange keys, and secure execution webhooks against catastrophic attacks.

Read More →
Analytics & NLP June 15, 2026
Integrating Alternative Data into High-Frequency Pipelines

Why pure L2 order book analysis is no longer enough, and how NLP sentiment feeds are processed for microsecond execution.

Read More →
Market Microstructure June 15, 2026
Fragmented Liquidity: Intelligent Order Routing Strategies

Navigating the complexities of dark pools, lit exchanges, and optimal execution algorithms in modern equity markets.

Read More →
Future Tech June 15, 2026
The Future of Quantitative Data Infrastructure

From FPGA hardware acceleration to microwave transmission networks, what the next decade of algorithmic trading infrastructure will look like.

Read More →
Engineering June 15, 2026
Overcoming API Rate Limits in High-Frequency Environments

Strategies for connection pooling, efficient data batching, and handling HTTP 429 Too Many Requests in rigorous institutional APIs.

Read More →
Execution June 15, 2026
Execution Quality: Why Infrastructure Trumps Strategy Logic

Even the most mathematically sound strategy will bleed capital if deployed on subpar infrastructure. Latency optimization is the true edge.

Read More →
AI & ML June 15, 2026
Machine Learning in HFT: Separating Signal from Noise

Deploying deep learning models in low-latency environments is notoriously difficult. We discuss the difficulties of overfitting on historical data.

Read More →
Market Structure June 15, 2026
The Shift to Direct Market Access

Why serious algorithmic trading firms abandon retail brokerages in favor of unadulterated Direct Market Access (DMA).

Read More →
Architecture June 15, 2026
Building a Scalable Tick Data Architecture

Storing and querying petabytes of raw tick data requires specialized time-series databases. We compare kdb+, InfluxDB, and ClickHouse.

Read More →
Macro June 15, 2026
Navigating Slippage: Managing Risk During Macroeconomic Spikes

How NFP and FOMC announcements instantly drain liquidity pools, and the quantitative models required to avoid catastrophic slippage.

Read More →
Data Science June 15, 2026
Level II Order Book Dynamics: Reading the Tape Programmatically

Extracting alpha from L2 data feeds requires sophisticated parsing. Learn how institutional quants analyze order book imbalances in real-time.

Read More →
Risk Management June 15, 2026
Designing Fault-Tolerant Trading Algorithms

How to implement robust circuit breakers, handle corrupted data packets, and manage failovers in high-frequency trading pipelines.

Read More →
Connectivity June 15, 2026
Institutional Cross-Connects: Why NY4 and LD4 Matter

An inside look at the physical fiber optic cross-connects that power the fastest data transmission between hedge funds and matching engines.

Read More →
Analysis June 15, 2026
The Fallacy of Retail Backtesting Platforms

Why testing algorithms on synthetic liquidity without factoring in true market depth and queue position leads to massive live-execution degradation.

Read More →
Protocols June 15, 2026
FIX Protocol vs. WebSockets: Choosing the Right Pipeline

A technical comparison between the Financial Information eXchange (FIX) protocol and modern WebSockets for streaming high-frequency data.

Read More →
Infrastructure June 15, 2026
Optimizing Algorithmic Execution: The Latency Arms Race

From colocated servers in NY4 to bypassing the TCP stack, we explore the hardware and software layers required for microsecond execution.

Read More →
Microstructure June 15, 2026
Market Microstructure: The Hidden Mechanics of Liquidity

Understanding the order book, tick data, and how liquidity providers interact with taker flow is crucial for latency-sensitive strategies.

Read More →

Empowering quantitative research with high-frequency market data and analytics.

AMII LTD
Plac Europejski 1
00-844 Warsaw, Poland

© 2026 HarvestGroup360 — a brand operated by AMII LTD.