# dcevm/dcevm

Dynamic Code Evolution VM for Java 7/8

Repository: https://github.com/dcevm/dcevm
Canonical: https://ross.abutalabs.com/products/dcevm
Language: Java
License Family: other
Last push: 2020-07-01T06:56:38+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4898, "days_push": 2254, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1857, forks 176 (observed 2026-08-28T04:05:44.947915+00:00)

## What it is
DCEVM is a patched OpenJDK HotSpot virtual machine that enables enhanced class redefinition for Java 7 and 8, allowing structural changes to loaded classes at runtime (such as adding/removing methods, fields, and even superclass changes). It is distributed as JVM library replacements (libjvm.so/jvm.dll/libjvm.dylib) or via a Gradle installer script.

## Use cases
- hot-reload java classes with structural changes during development
- modify class hierarchy at runtime without restarting the jvm
- enable dcevm hotswap in intellij idea for java 7/8
- patch openjdk hotspot to support full class redefinition
- replace libjvm to allow adding and removing fields and methods on reload
- avoid application restarts when refactoring java code

## When to choose
- you are stuck on java 7 or 8 and need enhanced hotswap beyond standard jvm capabilities
- you want to hot-reload classes with structural changes like superclass removal
- you build tooling that requires runtime class redefinition on older jvms

## When to avoid
- you are on java 11 or newer - use the Trava OpenJDK DCEVM-11 distribution instead
- you only need standard hotswap (method body changes) which the stock JVM already supports
- you need a supported, actively maintained JVM for production use

## Facets
- artifact type: library
- maturity: maintenance
- function: interpreter, compiler, developer-tools
- domain: programming-languages, developer-tools
- platform: windows, jvm
- tags: jvm, hotspot, class-redefinition, hotswap, java-7, java-8, openjdk, dynamic-code-evolution, patch, runtime-patching, linux, macos

## Member repositories
- dcevm/dcevm (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:44.947915+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:16:36.718611+00:00, confidence not recorded.
  - readme: https://github.com/dcevm/dcevm (fetched 2026-08-28T04:05:44.947915+00:00, sha 71855520232a)
- Data as of 2026-08-30T08:39:29.467469+00:00.