raspberry pi 5 · alpaca api · self-hosted · no cost
Monstra Pro
Monstra Pro is self-hosted software for Raspberry Pi that runs algorithmic strategies on your own device and places orders through your own Alpaca account.
Read this before you install
This software places real orders in a real brokerage account with real money.
It is provided as-is, with no warranty of any kind. It contains bugs. It can fail, place incorrect orders, place orders you did not intend, or fail to place orders at all. You are solely responsible for everything that happens in your Alpaca account. Losing money is possible, including losing everything in the account.
This is not financial advice. Monstra is not an investment adviser and does not provide investment advice.
How it works
Three steps
- 01
Install on your Pi
You write the image to a microSD card, boot the Raspberry Pi, and finish setup over SSH. Every step happens in a terminal.
- 02
Connect your own Alpaca credentials
You create an API key and secret inside your own Alpaca account and enter them during setup. The credentials are written to the device and stay on the device.
- 03
Select algorithms and an orchestration mode
You select up to 10 algorithms and one rule for distributing portfolio weight across them. The device runs that configuration until you change it.
What runs where
The split
Monstra provides the algorithm definitions and the software. Your device does everything else: it runs the algorithms, holds the API credentials, and places the orders.
distribution
Monstra
- algorithm definitions
- software releases
execution
Your Raspberry Pi
- runs the algorithms
- holds your API credentials
- decides and places orders
brokerage
Alpaca
- your brokerage account
- fills the orders
One direction only. There is no return path to Monstra. The device does not report back what it did.
Never sent to Monstra
- Alpaca API keys
- orders
- trades
- positions
- balances
- account activity
Monstra's servers never hold your Alpaca API keys. Monstra never places an order. Monstra never receives your trades, positions, balances, or account activity. This is a statement about where the code runs, not a claim about how well anything is guarded: the data never reaches Monstra because the software never sends it.
Trading mode
Paper trading is the default
The software connects to Alpaca paper trading out of the box. Paper trading uses simulated fills and no real money. This is where the software starts and where it stays until you change it.
Live trading is a separate, deliberate action. You enter live API credentials and change the trading mode explicitly. The software does not switch modes on its own, and there is no automatic move from paper to live.
# the mode the device runs in monstra-pro config get trading.mode paper
Configuration
What you select
Algorithms
You select up to 10 algorithms. Each one is a set of rules that produces orders. The logic of each algorithm is documented separately.
Individual stocks
Individual stocks can be included as positions alongside the algorithms. A stock included this way is held as a position and is not traded by any algorithm. It takes a share of portfolio weight like any other holding.
Orchestration modes
The orchestration mode is the rule that distributes portfolio weight across the algorithms you selected. You pick one.
Manual
You set a fixed allocation per algorithm. Weights do not change unless you change them. No interval applies.
Ranked
On an interval you define, the selected algorithms are ranked by recent performance. The N highest-ranked stay active and are weighted equally. The rest are allocated zero until the next ranking.
Weighted
On an interval you define, all selected algorithms stay active. Portfolio weight is distributed across them in proportion to recent performance.
These are three rules for distributing weight. They distribute it differently. Monstra makes no claim about how any of them behaves.
Requirements
What you need before you start
- Raspberry Pi 5
- 4 GB RAM or more, a microSD card, and a power supply. The image targets the Pi 5.
- Alpaca account
- Your own Alpaca account, with an API key and secret generated from it. Monstra does not open the account for you and cannot access it.
- Persistent internet and power
- The device stays online and powered while it runs. It is not built to be switched on around a session and off again afterwards.
- Command line familiarity
- Installation, configuration, and updates happen in a terminal over SSH. There is no one-click installer. This requires technical setup, and nobody will do it for you.
Known limitations
What this software does not do
It runs on your internet and your power
The device sits in your home. A power cut, a router reboot, an ISP outage, or an unplugged cable stops it. While it is down, orders can be delayed or never placed at all.
Monstra cannot see your device
Monstra has no visibility into whether the software is running correctly on any device. Monstra cannot tell that it crashed, that it is misconfigured, or that an order failed. Nothing on Monstra's side watches it for you.
There is no support guarantee
There is no support contract, no response time, and no obligation on anyone to answer a question, fix a defect, or publish another release.
It depends on Alpaca
Orders go through the Alpaca API. If Alpaca is unavailable, rate-limits a request, or rejects it, the software cannot place the order.
Updates are manual
The device keeps running the version you installed until you update it yourself. Algorithm definitions can change between releases.
It contains defects
This software is written by people and it has bugs, including bugs nobody has found yet. Some of them will only appear while it is placing orders.
Download
Install
Version 0.1.0, distributed as a Raspberry Pi image. Verify the checksum before you write the card.
# 1. download the image and verify it curl -LO https://downloads.monstra.pro/monstra-pro-0.1.0.img.xz curl -LO https://downloads.monstra.pro/monstra-pro-0.1.0.img.xz.sha256 sha256sum -c monstra-pro-0.1.0.img.xz.sha256 # 2. write it to a microSD card (replace /dev/sdX with your card) xz -d monstra-pro-0.1.0.img.xz sudo dd if=monstra-pro-0.1.0.img of=/dev/sdX bs=4M status=progress conv=fsync # 3. boot the Pi, then connect over SSH ssh monstra@monstra-pro.local # 4. run setup and enter your Alpaca paper credentials monstra-pro setup
Setup asks for an Alpaca API key and secret and writes them to the device. It leaves the trading mode on paper. After setup you select algorithms and an orchestration mode, and the device runs that configuration.