> ## Documentation Index
> Fetch the complete documentation index at: https://docs.phylax.systems/llms.txt
> Use this file to discover all available pages before exploring further.

# Development Effort

> Understanding the effort required to develop assertions

<Check>
  **Summary**

  * Comparable to writing Forge invariant tests when invariants are defined
  * Written in Solidity with familiar patterns
  * Few additional [cheatcodes](/credible/cheatcodes-overview) to learn
  * Main variable: whether invariants are already defined
</Check>

## Effort Factors

Development effort depends on whether invariants are already defined for your protocol.

### Invariants Defined

When invariants exist, writing assertions is similar to writing Forge invariant tests:

* **Workflow**: Write Solidity, test with `pcl test`(fork of `forge`), deploy via the [platform](https://app.phylax.systems)
* **Learning curve**: A small set of [cheatcodes](/credible/cheatcodes-overview) for snapshot reads (`PhEvm.ForkId`, `ph.loadStateAt`, etc.)
* **Familiarity**: Developers who write Forge tests can write assertions

### Invariants Not Defined

You can write assertions without pre-defined invariants, but having them makes the process easier, more structured, and lowers the risk of overlooking attack vectors.

Defining invariants involves identifying:

* States that should never occur
* Relationships that must always hold (e.g., total supply = sum of balances)

Some teams do this internally; others engage security researchers or auditors. For guidance, see [Intro to Invariants ↗](https://jstcz.eth.link/blog/2025/08/13/intro-to-invariants/).

## Testing Assertions

Testing assertions can take longer than writing them. However, assertion tests reuse existing protocol test infrastructure. Existing Forge test setups carry over with minimal to no additional effort.

See [Testing Assertions](/credible/testing-assertions) for patterns and best practices.

## Next Steps

<CardGroup cols={2}>
  <Card title="Quickstart" icon="rocket" href="/credible/pcl-quickstart">
    Write and deploy your first assertion
  </Card>

  <Card title="Assertion Guide" icon="code" href="/credible/write-first-assertion">
    Step-by-step guide to writing assertions
  </Card>

  <Card title="Cheatcodes" icon="wand-magic-sparkles" href="/credible/cheatcodes-overview">
    Learn the additional tools available
  </Card>

  <Card title="Testing" icon="flask-vial" href="/credible/testing-assertions">
    Test your assertions locally
  </Card>
</CardGroup>