# Simplicity theory and design

**URL:** https://community.simplicity-lang.org/c/simplicity-theory-and-design/10.md

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## [About the Simplicity theory and design category](https://community.simplicity-lang.org/t/about-the-simplicity-theory-and-design-category/16)

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**Author:** [@schoen](https://community.simplicity-lang.org/u/schoen)\
**Replies:** 0\
**Last updated:** [June 26, 2026, 8:23pm UTC](https://community.simplicity-lang.org/t/about-the-simplicity-theory-and-design-category/16 "2026-06-26T20:23:55Z")

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This category is meant for discussion about Simplicity and its architecture in conceptual and theoretical terms, as well as the goals and engineering trade-offs involved in the creation of Simplicity, as well as prospect…

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## [Hal-simplicity discussion](https://community.simplicity-lang.org/t/hal-simplicity-discussion/109)

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**Author:** [@ikripaka](https://community.simplicity-lang.org/u/ikripaka)\
**Replies:** 2\
**Last updated:** [November 10, 2026, 10:11am UTC](https://community.simplicity-lang.org/t/hal-simplicity-discussion/109 "2026-11-10T10:11:08Z")

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Hi everyone! We’re currently exploring ways to leverage hal-simplicity for our VS Code extension. hal-simplicity can be quite useful for: Simplicity program inspection program execution debugging calculation and veri…

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## [Padding problem: execution cost exceeded budget limit](https://community.simplicity-lang.org/t/padding-problem-execution-cost-exceeded-budget-limit/85)

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**Author:** [@KyrylR](https://community.simplicity-lang.org/u/KyrylR)\
**Replies:** 2\
**Last updated:** [October 5, 2026, 11:22am UTC](https://community.simplicity-lang.org/t/padding-problem-execution-cost-exceeded-budget-limit/85 "2026-10-05T11:22:48Z")

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When working on contracts that are doing a lot of hashes (checking Merkle Tree Proofs), quite often I had to add “padding” to the program itself to avoid having an error that says that execution cost exceeded budget. I a…

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## [\`comp\` and verifiable conjunctions](https://community.simplicity-lang.org/t/comp-and-verifiable-conjunctions/51)

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**Author:** [@apoelstra](https://community.simplicity-lang.org/u/apoelstra)\
**Replies:** 0\
**Last updated:** [August 11, 2026, 10:46pm UTC](https://community.simplicity-lang.org/t/comp-and-verifiable-conjunctions/51 "2026-08-11T22:46:43Z")

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Structurally, Simplicity has many similarities to Miniscript, a combinator language built on top of Bitcoin Script and which allows complex spending policies to be defined in an analyzable way. (Miniscript borrowed many …

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## [Why do the constant word jets have unit source type?](https://community.simplicity-lang.org/t/why-do-the-constant-word-jets-have-unit-source-type/42)

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**Author:** [@apoelstra](https://community.simplicity-lang.org/u/apoelstra)\
**Replies:** 1\
**Last updated:** [August 10, 2026, 6:30pm UTC](https://community.simplicity-lang.org/t/why-do-the-constant-word-jets-have-unit-source-type/42 "2026-08-10T18:30:50Z")

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It’s somewhat annoying that you can’t take an arbitrary expression and prefix something to it with constant &&& expression. This would require that the expression have the same input type as constant, which if constant i…