Wire a definition into a strategy slot so the engine evaluates it during backtests. Call after building a definition with builder_add_condition or builder_compose. Every strategy needs at least one entry rule to trade.

Roles

• entry — open a position when the definition fires (requires direction="long" or "short")
• exit — close the position when the definition fires (size_frac controls partial exits). Set direction="long" or "short" to scope it; omit direction to apply it to BOTH sides.
• gate — block all entries when the definition is false (evaluated first)

builder_attach_rule(strategy_id, definition_id, role="entry", direction="long")
builder_attach_rule(strategy_id, stop_id, role="exit", direction="long") # long only
builder_attach_rule(strategy_id, time_exit_id, role="exit")                  # BOTH

Directional entry groups

• Entry rules with the same direction are ANDed: all must fire on the same bar.
• Long and short groups are alternatives. If both fire on one bar, the signal conflicts and no order is placed.
• Bidirectional strategies enter only while flat.
• No same-bar reversal: an opposite signal while invested is diagnostic only. Even if an exit fills on that bar, it does not enter the other side; the complete opposite entry group must fire again on a later bar while flat.
• Sizing and exits whose direction is omitted are shared by both directions.

To express OR / NOT / sequence within one direction or for gates, combine conditions into one definition with builder_compose. Gate rules are ANDed; exit rules remain independent and any firing closes.

Exit ordering — there is no exit ranking. The compiler never assigns ExitRule.priority, so every condition exit carries the default and they are evaluated in attachment order, first match closing. fixed_targets and trailing_stop are not condition exits at all — they compile to standing stop/limit orders filled against the bar's OHLC.

Returns rule_id and definition_id. Use rule_id for builder_detach_rule.