Choose by what has to be true
Feature comparisons between MQL5 and Pine are long and rarely decide anything, because both platforms can express most rule-based strategies. A shorter question decides it: what has to be true for your strategy to be worth running at all?
| If this has to be true | Pick | Because |
|---|---|---|
| "it would have filled at a real price" | MetaTrader 5 | its tester can replay real broker-accumulated ticks with no simulation [2] |
| "I can iterate on the idea quickly" | TradingView | the script runs on the chart with no build step, and a change is one save away |
| "the spread cost is my broker's, not a guess" | MetaTrader 5 | tested against the data of the broker you will actually trade with |
| "it holds up over tens of thousands of bars" | TradingView, if your plan reaches | up to 40,000 bars on the top tier [3] |
| "nothing of mine has to stay switched on" | TradingView | the script runs on the chart, not on a machine you maintain |
| "it must place orders without me" | MetaTrader 5 | a Pine alert is a notification, not an order [4] |
That last row is the one that ends most of these debates, and it is worth being exact about.
The line Pine does not cross
A Pine strategy can raise alerts, and an alert created from a strategy can be set so order fill events also trigger it [4]. But an alert is a notification. Getting from a fired alert to a filled position needs a broker integration, and the delay between them is yours.
An MQL5 Expert Advisor is different in kind: it runs inside a terminal that is connected to your account, and it sends orders itself. That is the actual distinction — not language features, not indicator coverage.
And the detail that catches everyone once:
Alerts only trigger in the realtime bar. [4]
A backtest showing two hundred trades produces zero alerts. Historical fills are a replay; alerts are realtime events.
What each one asks of you in return
Neither is free, and the costs are of different kinds.
MetaTrader 5 needs a terminal running on a machine you control, which means that machine has to stay on and connected — hence the VPS most EA guides assume. It also makes your backtest only as good as the tick history your broker published, which varies. See deploying and maintaining an EA.
TradingView ties how much history you can test to your subscription tier
[3], and bounds each script: up to 40 unique request.* calls (64 on the top
plan), 64 plot counts, and 20 seconds of execution time on basic accounts, 40 on
others [3]. Those are generous for a rule-based strategy and are real ceilings
for anything elaborate.
The honest summary
Use TradingView to find out whether an idea is worth anything, because iterating is fast and the chart tells you immediately. Use MetaTrader 5 to find out whether it survives real fills, because only it can test against ticks that actually happened.
They are not competitors for the same job, and why their backtests cannot agree is a property of the engines rather than a fault in either.
Can you change your mind later?
Mostly yes, and the cost is not where people expect. Indicator names port almost for free — an RSI is an RSI. What does not port is everything around them.
The execution model is the real barrier
MQL5 is organised around event handlers: OnTick() runs when a new quote
arrives. Pine has no such handler. A Pine script runs once per historical bar
and repeatedly on the realtime bar [1], and you express "when this happens" as
a condition evaluated on each execution rather than as a callback.
So an MQL5 strategy that counts ticks, or acts on the n-th quote inside a bar, has no direct Pine translation. It has to be re-expressed in terms of bars or of a lower-timeframe request — and that re-expression is a change to the strategy, not a port of it.
Going the other way is easier: anything defined on confirmed bar closes moves between the two platforms with little friction, because both can express it.
The settings that look identical and are not
These are the dangerous ones, because the number carries over, compiles, runs, and means something else:
| Setting | TradingView | MetaTrader 5 |
|---|---|---|
| Slippage | slippage, in ticks | deviation in points — not the same unit |
| Commission | commission_value, read per commission_type | per-lot, from the broker's contract specification |
| Position size | strategy.fixed or strategy.percent_of_equity | lots, subject to the symbol's min, max and step |
| Session hours | a session string, read in the exchange's timezone | the broker's server time, which is usually neither UTC nor yours |
The session row causes the most silent breakage. A strategy that trades the
London open needs its session re-derived on each platform rather than copied —
the session-filter rules
cover the Pine half, including why our own generator emits hour(time, "UTC")
instead of a session string.
What to do if you genuinely might switch
Keep the strategy in a form that is neither language. A written specification — entry condition, exit condition, sizing rule, session, all with numbers — is the thing that ports cleanly, because it is what both platforms are expressing.
That is also what makes a strategy testable at all, and converting a manual strategy is the same exercise from the other direction. A specification you hold separately means switching platforms is a rebuild from a spec rather than a translation of code — which is faster, and produces a working strategy instead of a subtly different one.
One thing that never transfers
Your results. Two platforms modelling price inside a bar differently cannot produce the same equity curve, so a figure from one is not evidence about the other. If you switch, you re-test — and you fix the instrument, timeframe and date range explicitly on both sides first, or the comparison means nothing.
Tactix AI — Studio vs Guide
Tactix AI is AlfaTactix’s product assistant brand (open Tactix AI).
- Tactix Studio turns a one-sentence strategy description into a draft across Timeframe, Signals, Filters, and Risk in the visual Strategy Builder. You review and edit every field before Code Generator writes MQL5 or Pine Script.
- Tactix Guide explains the step you are on — what to fill, what a control means, or how to phrase a rule — without dumping untested source code.
That is form-first automation: the LLM never replaces Code Generator, and you keep plan limits and real-time validation.