LBlbalazscs·Aug 11, 2025
We are already living in an (almost) ideal world: https://github.com/raphw/byte-buddy/discussions/1798
In Byte Buddy is a code generation and manipulation library for Javaraphw
byte-buddy
Java2015–2025
raphw / byte-buddy
byte-buddy
Runtime code generation for the Java virtual machine.
5Distinct people
8Mentions
0Explicit recommenders
6.9KGitHub stars
What to know before exploring
What it is
Runtime code generation for the Java virtual machine.
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
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Also in these discussions
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This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 1:49:46 PM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by year8 dated mentions
Observed mentions: 2015-03-04 08:18:09 UTC to 2025-08-11 21:05:03 UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2015 | 2015-01-01 00:00:00 UTC | 2016-01-01 00:00:00 UTC | 1 | 1 | 0 |
| 2016 | 2016-01-01 00:00:00 UTC | 2017-01-01 00:00:00 UTC | 2 | 2 | 0 |
| 2017 | 2017-01-01 00:00:00 UTC | 2018-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2018 | 2018-01-01 00:00:00 UTC | 2019-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2019 | 2019-01-01 00:00:00 UTC | 2020-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2020 | 2020-01-01 00:00:00 UTC | 2021-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2021 | 2021-01-01 00:00:00 UTC | 2022-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 1 | 0 | 1 |
What Hacker News says
8 sourcesByte Buddy - runtime code generation for the Java virtual machine - https://github.com/raphw/byte-buddy
> It is stable and in use by distinguished frameworks and tools such as Mockito, Hibernate , Jackson, Google's Bazel build system and many others. Byte Buddy is also used by a large number of commercial products to great result. It is currently downloaded over 75 million times a year.
In Which open-source projects are widely used but maintained by just a few people?I glanced at your code examples and it looks quite similar to ByteBuddy[0], a Java library for manipulating JVM bytecode.
[0]: https://github.com/raphw/byte-buddy
In The plan-execute patternASM is far lower level than ByteBuddy. To write some ASM code you probably want to have some proficiency with the bytecode format itself (e.g. you're typically outputting individual JVM bytecode instructions ;(invokespecial,athrow,etc). Personally I'd probably always use ByteBuddy unless I had some very specific reason why not. For comparison, these two examples https://github.com/raphw/byte-buddy#changing-existing-classe... http://web.cs.ucla.edu/~msb/cs239-tutorial/ explain how to do a System.out.println wrapper around a method.
In one case, the developer writes `System.out.println`. In the other, the developer must individually get the static field System.err and push it to the stack, reference PrintStream's method println, including the arguments (Ljava.lang.String;)V. That means it takes an array of strings and returns void.
In Overriding C++ virtual functions at run timeIt's generally possible to rewrite loaded classes. Some changes are possible (e.g. replacing a method's body), others are not (adding new methods). The state of the art library for doing this at the application layer is ByteBuddy https://github.com/raphw/byte-buddy#changing-existing-classe... but this functionality is used by plenty of tooling - profilers such as YourKit rewrite methods to add telemetry - I've seen some security libraries attempt to add additional security related hooks.
In Overriding C++ virtual functions at run timeByte Buddy – JVM runtime code generation – adds support for Java 9 modules
3 points · Open discussionByte Buddy – runtime code generation for the JVM: version 1.0.0
Byte Buddy - an alternative to cglib and Javassist - has left the beta state: https://github.com/raphw/byte-buddy
2 points · Open discussionByte Buddy – runtime code generation for the JVM
55 points · Open discussion