Crypto HFT Stack — 101 for Dummies
**A note before we start:** you asked to learn about "legacy technology." The Infinite Field stack is the *opposite* of legacy — it's all cutting-edge 2020s crypto trading infrastructure. So this guide teaches you the modern concepts from scratch, then shows how one real firm assembles them. Where a piece *replaces* an older way of doing things, I'll point that out so you can see the "legacy vs modern" contrast.
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Part 1 — The Concepts (from zero)
Imagine you want to trade crypto automatically, faster and smarter than a human. To do that, four problems must be solved. Each concept below solves one problem.
Problem 1: "How do I hear what prices are doing, instantly?"
**The concept: WebSockets.**
Think of two ways to get news:
- **Old way (polling / HTTP requests):** You call the newspaper every 5 seconds and ask "anything new?" Most calls waste effort. You always find out *after* it happened. This is the "legacy" pattern — request, response, hang up, repeat.
- **Modern way (WebSockets):** You open *one* phone line to the exchange and leave it open. The moment a price changes, they shout it down the line to you. No asking. No waiting. No reconnecting.
For trading, milliseconds are money, so the open-line model wins. Every crypto exchange streams its live prices (the "market-data feed") over WebSockets.
> **Analogy:** Polling is refreshing your email inbox by hitting F5. WebSockets is a phone call that stays connected — the other side just talks when there's something to say.
Problem 2: "How do I actually place a trade on a blockchain?"
**The concept: Nodes and RPC.**
A blockchain (like Ethereum) is a shared ledger running on thousands of computers worldwide. To read it or write to it, you talk to one of those computers, called a **node**.
- **A node** is a computer running the blockchain software. It holds a copy of the ledger and knows the current state of everything.
- **RPC (Remote Procedure Call)** is just the *language/protocol* you use to ask a node to do something: "what's my balance?" or "submit this trade." Think of RPC as the ordering system at a drive-through — a fixed set of things you're allowed to ask for, in a fixed format.
Two ways to get a node:
- **Legacy/lazy way:** Rent access to *someone else's* node (a service like Infura/Alchemy). Easy, but you're one of thousands of customers sharing it — slower, and they see your activity.
- **Serious way:** Run *your own* node. More work, but you get the data first and nobody's watching your moves. Speed-obsessed trading firms run their own.
Problem 3: "How do I prove a trade is really from me — without getting robbed?"
**The concept: Keys, signing, and hardware wallets.**
On a blockchain there are no usernames and passwords. Instead:
- You have a **private key** — a secret number. Whoever holds it controls the money. Full stop.
- To make a trade, you **sign** it with that key. The signature mathematically proves "the key-holder authorized this" without revealing the key itself.
The danger: if your private key sits in a normal computer file and that machine is hacked, the money's gone instantly.
- **Software signing (riskier):** Key lives in the computer's memory. Fast, but exposed.
- **Hardware wallet signing (safer):** The key lives inside a dedicated tamper-resistant device (like a Trezor). The trade is sent *into* the device, signed *inside* it, and only the signature comes out. The key never leaves the hardware. Even if your main computer is compromised, the attacker can't extract the key.
There's also a refinement called **EIP-712 / typed-data signing.** Early crypto signing showed you an unreadable blob of hex — you were signing blind. EIP-712 structures the message so you (or your system) can see *exactly* what's being authorized ("sell 10 ETH at price X") before signing. It's the modern, safer replacement for blind signing.
Problem 4: "How do I know my whole system is healthy while it runs 24/7?"
**The concept: Observability / telemetry pipelines.**
A trading system is dozens of programs running nonstop. Something *will* break at 3 a.m. **Observability** means every component constantly emits logs and metrics ("I processed 4,000 messages," "latency spiked," "connection dropped"), and a **telemetry pipeline** collects, routes, and stores all of it in one place so you can watch dashboards and get alerted.
> **Analogy:** It's the cockpit instrument panel for the trading engine. Without it, you're flying blind and only find out you crashed after the money's gone.
Bonus concept: "Why does the *programming language* matter?"
Because HFT lives and dies on speed. Languages fall roughly into:
- **Slower but easy** (Python, JavaScript): great for research and web apps, too slow and unpredictable for the hot path where microseconds count.
- **Fast and predictable** (C, C++, and now **Rust**): compile down close to the machine, no unpredictable pauses.
**Rust** is the modern choice: as fast as C/C++, but with built-in safety guarantees that prevent whole classes of crashes and memory bugs. For a firm moving real money automatically, "fast AND won't randomly corrupt itself" is the dream. Rust replacing C++ is one of the clearest "modern vs legacy" shifts in this space.
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Part 2 — How Infinite Field Assembles These
Now re-read Part 1's four problems. Infinite Field's public tools map almost one-to-one onto them. Here's the assembly, problem by problem.
The venue: Hyperliquid
First, context. **Hyperliquid** is a blockchain built specifically for trading perpetual futures ("perps") — a fast, on-chain exchange. Multiple clues show it's Infinite Field's primary battlefield:
- They wrote their own **Hyperliquid SDK** (`hypersdk`) — a toolkit for talking to it.
- They run their own **Hyperliquid archive node** (`nanoreth`, built on **Reth**, a modern Rust Ethereum node).
You don't build custom tooling *and* run your own node for a venue you dabble in. Hyperliquid is home base.
Problem 1 (hear prices) → `yawc`
They built **`yawc`**, their *own* WebSocket implementation in Rust, with compression. They could have used an off-the-shelf one — instead they built their own to control latency down to the microsecond. This is the market-data lifeline from Concept 1, hand-tuned.
Problem 2 (place trades) → `alloy`, `jsonrpsee`, `nanoreth`
- **`alloy`** is the modern Rust toolkit for talking to Ethereum-style blockchains (RPC, transports, transaction building). It's the current-generation replacement for older Ethereum libraries.
- **`jsonrpsee`** is the Rust library that actually speaks the RPC protocol under the hood.
- **`nanoreth`** is their own node, so they read the chain *first-hand* instead of renting someone else's — exactly the "serious way" from Concept 2.
Problem 3 (sign safely) → `trezor-firmware`, `alloy-signer-trezor`, `rage`
- **`trezor-firmware`** — they forked the firmware of the Trezor hardware wallet. Keys live in tamper-resistant hardware.
- **`alloy-signer-trezor`** — the glue that lets their trading code send transactions into that Trezor for **EIP-712 typed-data signing** (the readable, modern signing from Concept 3).
- **`rage`** — a Rust encryption tool (an implementation of `age`) for encrypting secrets and config at rest.
Together: serious key custody. They're clearly moving enough size that a stolen key would be catastrophic, so they invested in hardware-backed, structured, encrypted signing.
Problem 4 (stay healthy) → `vector`
**`vector`** is a high-performance observability pipeline — the instrument panel from Concept 4, collecting logs and metrics across their whole system.
The through-line: Rust everywhere
Every single tool above is **Rust** (with some **C** inside the Trezor firmware). No Python, Go, or JavaScript in the core. This is a deliberate, latency-obsessed choice — the modern high-performance stack, top to bottom.
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Part 3 — The One-Page Cheat Sheet
| Problem | Concept | Legacy way | Modern way | Infinite Field's tool |
|---|---|---|---|---|
| Hear live prices | WebSockets | Polling (ask repeatedly) | Open streaming line | `yawc` |
| Read/write the chain | Nodes + RPC | Rent someone's node | Run your own node | `nanoreth`, `alloy`, `jsonrpsee` |
| Authorize trades safely | Keys + signing | Blind software signing | Hardware + typed-data (EIP-712) | `trezor-firmware`, `alloy-signer-trezor`, `rage` |
| Stay alive 24/7 | Observability | Check logs manually | Automated telemetry pipeline | `vector` |
| Go fast | Language choice | C/C++ (fast, unsafe) | Rust (fast AND safe) | *everything* |
| Where they trade | The venue | — | On-chain perp DEX | Hyperliquid (`hypersdk`) |
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What to explore next (in order)
1. **WebSockets** — the easiest concept to get hands-on with; you can open one in a browser console in minutes.
2. **What a blockchain node actually does** — the mental model that unlocks everything crypto.
3. **Public vs private keys and signing** — the security foundation.
4. **Why Rust** — once you feel *why* speed and safety both matter, the whole stack's logic clicks.
> **Remember the framing:** nothing here is legacy. If you want a true legacy-vs-modern study, the richest contrasts are *polling → WebSockets* and *C++ → Rust*. Those two show the old world and the new world most clearly.