---
# System prepended metadata

title: Development update 4

---

# Development update 4

This is my fourth developoment update for the Ethereum CDAP programme.

## Task

I have implemented the following opcodes in the [execution-specs](https://github.com/ethereum/execution-specs):
1. CALL
2. CALLCODE
3. SUICIDE A.K.A SELFDESTRUCT

This code has been built on my previous work on [message call](https://hackmd.io/UG8Q0RbsTDS-dgKZr9EEIg). The PR for `message call` has not been merged yet but it is approved and is open for others to review before merging.

Besides implementing these opcodes, I fixed some bugs in the refund gas code. This fix has been added to my self destruct PR.


## Code

The PR for the above mentioned opcodes can be found at:
- `CALL and CALLCODE` - https://github.com/ethereum/execution-specs/pull/316
- `SUICIDE A.K.A SELFDESTRUCT` - https://github.com/ethereum/execution-specs/pull/317

## What's Next?

I am currently working on precompiled contracts. The PR is stuck at the moment because some state tests are failing. What's interesting is that the block hash is matching but not the state root. I will write more about the test failures in my next update.

