Javit ću ti se čim stignem u Zagreb.

In standard Croatian, when the future auxiliary ću comes after the infinitive, the infinitive usually drops its final -i:

• javiti + ću → javit ću

So:

• Javit ću ti se = correct
• Ja ću ti se javiti = also correct
• Javiti ću ti se = nonstandard

This is a very common thing learners notice in the future tense.

Javiti se is a very common verb expression meaning:

• to contact someone
• to get in touch
• to check in
• to let someone know
• sometimes to call/message

Literally, it is related to announcing oneself, but in everyday Croatian it often just means to contact.

Compare:

• Javit ću ti se. = I’ll contact you / I’ll get in touch.
• Javi mi se! = Contact me! / Get in touch!

They do different jobs.

• ti = to you
• se = part of the verb javiti se

So javiti se nekome means to contact someone.

Here:

• ti is the indirect object pronoun in the dative
• se is not yourself here; it belongs to the verb

So javit ću ti se is best understood as one whole pattern:

• javiti se + dative person
• to get in touch with someone

Because Croatian normally uses the present tense after time words like čim when talking about the future.

So:

• čim stignem u Zagreb = as soon as I arrive in Zagreb

This is actually similar to English:

• We say as soon as I arrive, not usually as soon as I will arrive

So even though the event is future in meaning, the verb in the čim clause stays in the present.

Čim means as soon as.

It emphasizes that one thing happens immediately after another.

• Čim stignem u Zagreb, javit ću ti se. = As soon as I arrive in Zagreb, I’ll contact you.

If you used kad, the meaning would be more like when:

• Kad stignem u Zagreb, javit ću ti se. = When I arrive in Zagreb, I’ll contact you.

Both are possible, but čim sounds more immediate.

Because Croatian changes the case depending on whether you mean movement or location.

• u Zagreb = movement to / into Zagreb
• u Zagrebu = location in Zagreb

Here the verb stignem means I arrive, so Zagreb is the destination. That is why Croatian uses the form for movement:

• stignem u Zagreb

Compare:

• Sad sam u Zagrebu. = I am in Zagreb now.
• Sutra stižem u Zagreb. = I’m arriving in Zagreb tomorrow.

Here Zagreb is in the accusative singular, because it follows u with movement toward a destination.

For many masculine inanimate nouns in Croatian, the accusative looks the same as the nominative, so:

• Zagreb = nominative
• Zagreb = accusative

But in the locative you get:

• u Zagrebu = in Zagreb

So the case changes, even if the accusative form itself does not visibly change.

Croatian often leaves out subject pronouns because the verb ending already shows the person.

• ću and stignem clearly show I

So Javit ću ti se čim stignem u Zagreb naturally means:

• I’ll contact you as soon as I arrive in Zagreb

You can add ja for emphasis:

• Ja ću ti se javiti čim stignem u Zagreb.

That would sound more like I will contact you... with extra emphasis or contrast.

Yes, Croatian word order is flexible, although not completely free.

These are all natural:

• Javit ću ti se čim stignem u Zagreb.
• Čim stignem u Zagreb, javit ću ti se.
• Ja ću ti se javiti čim stignem u Zagreb.

The basic meaning stays the same, but the focus changes a little.

One important thing: short unstressed words like ću, ti, and se are clitics, and they tend to appear near the beginning of their clause in a fixed order. That is why combinations like ti se sound natural, while other orders may not.

Yes. This is the standard future I tense in Croatian.

It is formed with:

• the present of htjeti as an auxiliary
• plus the infinitive of the main verb

For I will:

• ću

So:

• javit ću = I will contact
• doći ću = I will come
• vidjet ću = I will see

In a fuller form, you could think of it as:

• ja ću javiti
• but with javiti se, the natural sentence is javit ću ti se

They are perfective verbs.

That means they describe actions as complete events:

• javiti se = to contact / get in touch once, as a completed act
• stići / stignuti = to arrive, to reach a destination

This fits the sentence well, because the speaker means:

1. first the arrival is completed
2. then the contact happens

In Croatian, perfective present forms often refer to the future in clauses like this:

• čim stignem = as soon as I arrive

A more imperfective verb would give a different feel and usually would not fit this sentence as well.

Very often, yes.

The common pattern is:

• javiti se + dative
• javit ću se mami
• javio sam se profesoru
• javi mi se

So in your sentence:

• ti is the dative form of you

That is why the structure is not like English contact you directly, but more like:

• announce oneself to someone
• which in normal English becomes contact someone

Yes, absolutely.

That version is correct and natural. The difference is mainly nuance:

• čim stignem = as soon as I arrive
• kad stignem = when I arrive

So čim sounds a bit more immediate and often more reassuring, as if the speaker promises to do it right away.