Overview
Precision Journal began as the ordinary thing — a place to log trades — and became something else once it was clear that logging is not the problem. Traders already have the data. What they do not have is a reason to look at it again, or anything to stop them repeating the mistake tomorrow.
We built it as a web application with a companion Android build, on top of a broker connection that imports fills automatically so nothing depends on the discipline of manual entry.
The challenge
A journal that only reports after the fact arrives too late to change anything. The habit it asks for — write everything down, review it later — is exactly the habit an undisciplined trader does not have.
The technical half of the problem was trust. Connecting software to a brokerage account is a serious thing to ask someone to do, and any integration that could place an order would be a much bigger promise than a journal needs to make.
What we did
The broker connection is strictly read-only. It can see fills and can never place, modify, or cancel an order — a constraint enforced at the integration layer rather than a policy in the documentation.
Rules the trader sets before a session are enforced during it, not summarised afterwards. Replay then ties the chart, the notes, the risk state, and the rule events to one playhead, so a decision can be watched rather than reconstructed from memory.
Every number the app reports is computed from the trader’s own data in a domain layer with its own tests. Written summaries only narrate figures that were already calculated — nothing is estimated in prose.
What it does
- Read-only broker connections with automatic fill import
- Session replay across price, notes, risk, and rule events
- Playbooks measured independently of overall account performance
- Rules enforced live, during the session
- Prop-firm drawdown tracked forward, not reported after
- Light and dark themes across the whole application
- Subscription billing