Long-term support (LTS)
Long-term support is the period in which a software version no longer gets new features but still receives critical fixes and security patches.
Most frameworks and runtimes release major versions on a schedule and cannot maintain all of them forever. They publish a support policy that divides the life of each version into phases. During active support the version receives features and regular fixes. During long-term support, or LTS, it receives only critical fixes and security patches. After that, the version is end of life.
Through version 21, the Angular team's policy gave each major version six months of active support followed by twelve months of LTS; from version 22 it is twelve months of each. Node.js designates its even-numbered releases as LTS lines and maintains them for a longer period.
Example
A team runs an Angular major version that entered LTS a few months ago. A security advisory is published for the framework. The Angular team releases a patch for that version, and the team applies it with a small update. A second team, on a version that left LTS long ago, gets no patch. It has to upgrade several major versions under time pressure or accept the risk.
Common misunderstanding
LTS is often read as "safe to stay on for a long time". It is a window for planning the next upgrade. Ordinary bugs are generally not fixed in LTS versions, and libraries in the ecosystem move on to newer major versions.
The label also varies by project. Node.js LTS, Angular LTS and a vendor's commercial LTS offer have different lengths and different guarantees, so read the policy of each dependency.
AngularJS is the reference case. Its LTS period ended on December 31, 2021, and no official patches have been published since. A sound practice is to track the support dates of the framework, the runtime and the main libraries in one place, and to schedule upgrades before LTS ends. The AngularJS end-of-life options guide covers what to do afterward.
Why it matters. Support windows set the calendar for upgrades and migrations. A platform with many micro-frontends needs a shared policy on how far behind any of them may fall.
Related terms
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