How does Lecturer in UK compare to other systems? I have never lived in UK, I did my graduate studies in the US. I was a postdoc in Europe, but the situation there seemed grim, I applied for a few positions only, one of them was this junior prof job in Germany (in theory, an assist prof equivalent of US ) though I figured out despite it being an assistant professorship, it is somewhere near the lecturer position of USA and a bit post-doc? So definitely not as an assistant prof equivalent of a US system in practice. Perhaps a research leader junior prof position could work better in that sense. But how does it work in UK? Currently I am in my country of origin, to be fair, the work is good, practically Tenured (what I need to do is very minimal to complete the track), there are some opportunities for research that I need to apply to (I am certain some grants would be easy with my background meaning a PhD abroad, if not the more challenging), but the university / department and students lack research vigor in every way And research is all I want to do to be honest, it is not a top notch school, I simply wasn't able to attend to some interviews while I was living abroad for top tier private unis and now positions are canceled, and the top tier state schools require just too much paperwork which might take years. I am happy with the job in certain ways, but it is not fulfilling for me in research and standing.
Now, I see this great fit in UK, at a top university, I know the professors there, it is so fitting to my research line etc. Though I don't know anything about the system and how much job safety there is. It is for about one year only, but with a chance to extend the contract. Now that I have an actual job to lose, and a pandemic, I feel like I could use some more information on

where the lecturers stand,  what is the usual timeline,  are people
offered tenure track positions afterwards?  how long it takes?  what
it requires?  How much research is involved? (it implies both
coursework and grad students/research opportunity) etc in the ad.

Also, I have never been confident in just asking for a job, so I saw this ad online (I always only apply through listed ads), but I know many people put ads only after they have their strong candidate. Although I know the prof there I don't want to ask, at the same time I feel a bit uneasy applying if they already have a candidate. How does it usually work? Also, not sure whether they would prefer someone living abroad during a pandemic.
&quot;Lecturer&quot; is the main entry-point academic rank in the UK system, and spans quite a wide range of pay grades: someone at the top of the lecturer pay bracket can easily have 10-15 years more experience than someone at the bottom. Promotion is usually to Senior Lecturer, and then to Reader and Professor. Nearly all Professors will have started out as lecturers.
The precise duties of a lecturer will vary between institutions, but typically involve a balance of research, teaching, and administrative responsibilities. One sometimes sees positions advertised as 'teaching-focussed': this means a higher teaching load and limited expectations of research output (and often an assumption that any research you do produce will focus on pedagogy).
Jobs may be advertised as 'fixed-term'/'temporary' or 'permanent'. Permanent jobs are more-or-less what they sound like: positions supported by the university's central funds, which are expected to continue indefinitely (though lecturers can be made redundant if, say, the university decides to close or merge departments in the face of falling enrolments). Often permanent jobs will have some element of probation, with a review 1-5 years after appointment. Each institution has its own procedures around this: in some it is purely an internal administrative process; in others it is more similar to a US tenure review, with external referees and the like. However, it is much less of a hurdle than the US tenure process, and failing to pass probation is rare.
Fixed-term jobs are usually supported by transient funding sources, and often arise because a permanent job-holder is expected to be on leave for a period (e.g. maternity cover), or has 'bought themselves out' of teaching responsibilities for the duration of a major grant. Whereas new permanent hires often get a soft start, with a reduced initial teaching load, fixed-term appointees may find themselves immediately lumbered with the teaching responsibilities of whoever they are replacing. Invariably adverts will make vague claims about a 'possibility of extension', but you should not place much weight on this: there may not be a clear plan for where the funds would come from.