Do Indonesian shipping businesses completely shut down for Ramadan?

Ramadan is a national holiday and the tradition is pulang kampung, go home to your village.
Not everything closes but it gets very quiet.
The mass return has already started but will get crazy from Monday.

As for shipping, I have no clue but I suspect many of the people you need to talk to won't be at their desks.

Ramadan is actually the fasting month leading up to the highly important Idul Fitri holiday which this year is August 8 and 9.

During the fasting month...the weeks leading up to Idul Fitri, you will find most all businesses open as usual, and this is particular so with all important shipping businesses.

Several days prior to Idul Fitri and for several days after is when the mass exodus of the faithful to their homes takes place and many businesses which are Muslim owned will be closed.

However, keep in mind that while Indonesia is a "very Muslim country" there are lots of business which are Chinese/Indonesian owned and that will remain open during the Idul Fitri holiday.

Moreover, while you haven't specified what part of Indonesia you are asking about, there are areas of Indonesia which are primarily Christian or other religions, such as Bali which is predominantly Hindu and where businesses will be open right through all of Ramadan and Idul Fitri. 

Express Carriers such as Fed Ex and DHL will only be closed on August 8 and 9.

Thanks for your responses everyone! Very explanatory.

At this point, I think I'll wait until after August 9 to get started on finding shipping industry partners...even if some people are at work, it seems like most businesses will be in a more normal rhythm at that time.

I think linkedin will be a good start to listing the ocean liners and freight forwarding companies in Indonesia as some of their top management also expats I doubt Ramadhan has effect for them if its only to read emails. For partner company searching it can be little bit tricky maybe you can start by identify association for logistic or ocean liners industry in Indonesia to understand the industry structure as it can be most of the vessel already have the system on board then have to identify the supplier for that etc.

For visiting date mostly business will freeze (not many people in the office or offices completely shutdown) for 2 weeks in Indonesia during Eid festive which is I expect start from 5 and back on at 19 August.

Btw I work for market consulting based on research and I can share few words if needed for fun.