Learn Hardcore Russian: Новый подписчик пишет мне тёплое сообщение. - A new subscriber writes me a warm message.

On social media, a подписчик is a follower/subscriber (YouTube, Instagram, Telegram, etc.).
For a newspaper or magazine, подписчик is also used for a paying subscriber.

So in modern Russian it works both for online followers and traditional subscriptions; context tells you which one is meant.

Why is it новый подписчик and not some other form of новый?

Новый is the masculine singular nominative form of the adjective новый (new).

Подписчик is a masculine noun in the nominative case (it’s the subject of the sentence).
Adjectives must agree with nouns in gender, number, and case.

So:

новый подписчик – masculine, singular, nominative
If it were a feminine noun, it would be новая подписчица (see below).
For a neuter noun, it would be новое сообщение (new message).

Why is подписчик masculine? What if the subscriber is a woman?

Grammatically, подписчик is a masculine noun (it ends in -чик, a typical masculine ending). It can refer to a subscriber of any gender, especially in a generic way.

If you specifically want to emphasize that the subscriber is female, you can say:

новая подписчица – a new female subscriber

So:

новый подписчик – new subscriber (gender-neutral in meaning, masculine in grammar)
новая подписчица – explicitly female subscriber

Why is the verb пишет used here, and how is it formed?

Пишет is the 3rd person singular present tense of the verb писать (to write, imperfective).

Conjugation of писать (present tense):

я пишу – I write
ты пишешь – you write (singular informal)
он/она/оно пишет – he/she/it writes
мы пишем – we write
вы пишете – you write (plural / formal)
они пишут – they write

The subject подписчик is singular (he/she), so you need пишет. The present tense here can mean:

right now: A new subscriber is writing me a warm message.
regular/habitual: A new subscriber (usually) writes me a warm message (less likely in this exact sentence, but still grammatically possible).

Why is it мне and not меня or я?

Мне is the dative case of я (I), used for an indirect object: to me / for me.

я – I (nominative, subject)
меня – me (genitive/accusative; often direct object)
мне – to me / for me (dative; indirect object)
мной – by me / with me (instrumental)
обо мне – about me (prepositional)

In пишет мне тёплое сообщение, the message is being written to me, so Russian uses the dative: мне.

Why do we say пишет мне, without a preposition, instead of something like пишет ко мне?

In Russian, the recipient of communication verbs is normally in the dative case without a preposition:

писать кому-то – to write to someone
звонить кому-то – to call someone (on the phone)
говорить кому-то – to speak to someone

So пишет мне means writes to me; мне alone (in dative) already contains the meaning to me.

Ко мне exists, but it means towards me / to my place in a physical sense, not as a recipient of a message:

Он идёт ко мне. – He is coming to me (to my place).

What does тёплое mean here? Is it literally “warm” or something like “kind”?

Literally, тёплый means warm (temperature). In emotional contexts, тёплый / тёплое often means warm, kind, affectionate, friendly.

So тёплое сообщение is:

literally: a warm message
naturally in English: a kind / warm-hearted / friendly message

This is a common metaphorical use in Russian: тёплые слова, тёплое письмо, тёплый приём (warm words, warm letter, warm welcome).

Why is it тёплое сообщение, not тёплый сообщение?

Because сообщение is a neuter noun, and the adjective must match it in gender, number, and case.

Nominative singular forms of тёплый (warm):

masculine: тёплый дом
feminine: тёплая погода
neuter: тёплое сообщение

Сообщение is neuter, so the correct form is тёплое сообщение.

How do we know that сообщение is neuter, and what does the word mean?

Сообщение means message / notification / announcement / report, depending on context. Here it clearly means message.

Grammatically:

Most nouns ending in -е or -ие in the nominative singular are neuter.
Сообщение ends in -ие, so it’s neuter.

That’s why adjectives with it use neuter forms:

интересное сообщение – an interesting message
важное сообщение – an important message
тёплое сообщение – a warm message

Russian has no articles, so how do we know if this means “a new subscriber” or “the new subscriber”?

Russian does not have articles (a / an / the). The noun новый подписчик on its own is neutral in that sense. Whether you translate it as a or the depends on context:

a new subscriber – if you are introducing this person for the first time.
the new subscriber – if both speaker and listener already know which new subscriber is meant (for example, you already talked about them).

The Russian sentence itself doesn’t force one or the other; English translation must choose based on context.

Can the word order be changed? For example, can I say Новый подписчик пишет тёплое сообщение мне?

Russian word order is flexible, but not all orders sound equally natural.

The most neutral and natural here is:

Новый подписчик пишет мне тёплое сообщение.

You can say Новый подписчик пишет тёплое сообщение мне, but it sounds a bit marked or stylistically odd in everyday speech; it gives extra emphasis to мне at the end. More typical variations would be:

Мне пишет новый подписчик тёплое сообщение. – extra focus on мне (to me).
Новый подписчик мне пишет тёплое сообщение. – mild emphasis on мне.

All these are grammatically possible; choice depends on what you want to emphasize.

How would the sentence change if I want to say “A new subscriber wrote me a warm message” (completed action in the past)?

You would usually switch to the perfective verb написать in the past tense to show a completed action:

Новый подписчик написал мне тёплое сообщение. – A new subscriber wrote me a warm message.

Compare:

пишет (from писать) – is writing / writes (ongoing or habitual)
написал (from написать) – wrote / has written (completed, one-time action)

For a female subscriber (explicitly):

Новая подписчица написала мне тёплое сообщение.

What’s the difference between пишет мне тёплое сообщение and пишет мне тёплое письмо?

Both are possible, but there is a nuance:

сообщение – message (neutral, modern, often electronic: text message, chat message, app notification, etc.).
письмо – letter; traditionally a paper letter, but in modern usage can also be an email.

So:

пишет мне тёплое сообщение – more like a message in a chat/app/social media.
пишет мне тёплое письмо – sounds like a longer, more personal letter (paper or email).

Why does сообщение keep the same form here? Isn’t it the direct object and supposed to be in the accusative?

Yes, тёплое сообщение is the direct object of пишет and is in the accusative case. However, for neuter inanimate nouns, the nominative and accusative forms are identical.

So:

Nominative: тёплое сообщение
Accusative (inanimate, neuter): тёплое сообщение

You only see a difference with:

masculine animate nouns (e.g. вижу нового подписчика)
many feminine nouns (e.g. читаю новую книгу vs. nominative новая книга)

Why is there ё in тёплое? Can it be written as теплое?

The letter ё is always pronounced [yo]. So тёплое is pronounced approximately [tyóplaye].

In modern Russian writing, it’s very common to drop the dots and write е instead of ё, especially in ordinary texts. So you will often see:

тёплое сообщение
written as: теплое сообщение

The pronunciation stays тёплое. In dictionaries, textbooks, or when clarity is important, the dots over ё are usually kept.