So am I being impolite or helpful by interjecting in these meetings?

In general, yes - it's impolite to interject in meetings to which you haven't been invited.

If this is actually a meeting led by a manager (rather than an informal conversation, for example), then you should probably ask permission before deciding to join in.

What is best course of action?

Since you are on good terms with the manager in question, you should talk with him/her first.

You could say something like "When you meet at your desk like that, I can't help but overhear. In particular, when you talked about the migration to Git, I had some information that could help. Would you like me to jump in and join the conversation in those cases?"

The manager might then choose to invite you to the meetings, or invite you whenever your opinion is needed, or move the meetings to somewhere else so as to not disturb you.

Let your future actions be guided by this discussion.

So am I being impolite or helpful by interjecting in these meetings?

In general, yes - it's impolite to interject in meetings into which you haven't been invited.

If this is actually a meeting led by a manager (rather than an informal conversation, for example), then you should probably ask permission before deciding to join in.

What is best course of action?

Since you are on good terms with the manager in question, you should talk with him/her first.

You could say something like "When you meet at your desk like that, I can't help but overhear. In particular, when you talked about the migration to Git, I had some information that could help. Would you like me to jump in and join the conversation in those cases?"

The manager might then choose to invite you to the meetings, or invite you whenever your opinion is needed, or move the meetings to somewhere else so as to not disturb you.

Let your future actions be guided by this discussion.

So am I being impolite or helpful by interjecting in these meetings?

In general, yes - it's impolite to interject in meetings to which you haven't been invited.

What is best course of action?

Since you are on good terms with the manager in question, you should talk with him/her first.

You could say something like "When you meet at your desk like that, I can't help but overhear. In particular, when you talked about the migration to Git, I had some information that could help. Would you like me to jump in and join the conversation in those cases?"

The manager might then choose to invite you to the meetings, or invite you whenever your opinion is needed, or move the meetings to somewhere else so as to not disturb you.

Let your future actions be guided by this discussion.

So am I being impolite or helpful by interjecting in these meetings?

In general, yes - it's impolite to interject in meetings to which you haven't been invited.

If this is actually a meeting led by a manager (rather than an informal conversation, for example), then you should probably ask permission before deciding to join in.

What is best course of action?

Since you are on good terms with the manager in question, you should talk with him/her first.

You could say something like "When you meet at your desk like that, I can't help but overhear. In particular, when you talked about the migration to Git, I had some information that could help. Would you like me to jump in and join the conversation in those cases?"

The manager might then choose to invite you to the meetings, or invite you whenever your opinion is needed, or move the meetings to somewhere else so as to not disturb you.

Let your future actions be guided by this discussion.