# Contract runner configuration **URL:** \ **Category:** Developers\ **Created:** [19 January 2021 07:19 UTC](https://talk.jelurida.com/t/contract-runner-configuration/132 "2021-01-19T07:19:40Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![lior.yaffe](https://talk.jelurida.com/letter_avatar_proxy/v4/letter/l/ecb155/32.png) [@lior.yaffe](https://talk.jelurida.com/u/lior.yaffe)\ **Post date:** [19 January 2021 07:19 UTC](https://talk.jelurida.com/t/contract-runner-configuration/132/1 "2021-01-19T07:19:40Z")
[shugo](https://app.slack.com/team/U5SJ8B2LE) [9:37 PM](https://ardornxt.slack.com/archives/C0XP71MBL/p1610998660038800) Does anyone know: when the ContractRunner config.json is loaded on the ContractNode, is it also uploaded to the blockchain? Can sensitive data be inside the config.json or would everyone see it? ---
**Author:** ![lior.yaffe](https://talk.jelurida.com/letter_avatar_proxy/v4/letter/l/ecb155/32.png) [@lior.yaffe](https://talk.jelurida.com/u/lior.yaffe)\ **Post date:** [19 January 2021 07:20 UTC](https://talk.jelurida.com/t/contract-runner-configuration/132/2 "2021-01-19T07:20:04Z")
[riker](https://app.slack.com/team/U0K1LKUCB) [10:33 PM](https://ardornxt.slack.com/archives/C0XP71MBL/p1611002037042600) No, config.json is a workstation specific file that is never uploaded to the blockchain, you can also encrypt the contract runner configuration [Node Processes Configuration - ArdorDocs](https://ardordocs.jelurida.com/Node_Processes_Configuration). The [Lightweight Contracts - ArdorDocs](https://ardordocs.jelurida.com/Lightweight_Contracts#Upload_Parameters_Configuration_File) API name is a bit misleading as it is used to upload the contract runner config from the client to a remote node but again this configuration is never registered on the blockchain. ![ardordocs.jelurida.com](https://talk.jelurida.com/uploads/default/original/1X/17b3291fc6396f9900fd3d8e11a953733b8312e8.png)[ardordocs.jelurida.com](http://ardordocs.jelurida.com) [Node Processes Configuration](https://ardordocs.jelurida.com/Node_Processes_Configuration) This guide explains how to use the Processes feature to save and store configurations of the node that are normally lost upon restart. ![ardordocs.jelurida.com](https://talk.jelurida.com/uploads/default/original/1X/17b3291fc6396f9900fd3d8e11a953733b8312e8.png)[ardordocs.jelurida.com](http://ardordocs.jelurida.com) [Lightweight Contracts](https://ardordocs.jelurida.com/Lightweight_Contracts#Upload_Parameters_Configuration_File) Lightweight Contracts represent a framework for developing a layer of automation on top of the existing Ardor APIs. ---
**Author:** ![lior.yaffe](https://talk.jelurida.com/letter_avatar_proxy/v4/letter/l/ecb155/32.png) [@lior.yaffe](https://talk.jelurida.com/u/lior.yaffe)\ **Post date:** [19 January 2021 07:20 UTC](https://talk.jelurida.com/t/contract-runner-configuration/132/3 "2021-01-19T07:20:15Z")
[shugo](https://app.slack.com/team/U5SJ8B2LE) [10:39 PM](https://ardornxt.slack.com/archives/C0XP71MBL/p1611002340045600) [@riker](https://ardornxt.slack.com/team/U0K1LKUCB) I have a ContractRunner node running Contract "X" , Logged in and running with Account X (config.json was loaded and running). Then I logged in to the same not with Account Y and tried to load a different config.json for a different contract. Everything was separate except that it was running on the same node. But I was not able to load the second config.json, nothing happened all the time. Until I restarted the node, I could load the second config.json.Is this something that you have experience before? ---
**Author:** ![lior.yaffe](https://talk.jelurida.com/letter_avatar_proxy/v4/letter/l/ecb155/32.png) [@lior.yaffe](https://talk.jelurida.com/u/lior.yaffe)\ **Post date:** [19 January 2021 07:20 UTC](https://talk.jelurida.com/t/contract-runner-configuration/132/4 "2021-01-19T07:20:30Z")
[Sergi Baila](https://app.slack.com/team/UK5UM9HAT) [9:17 AM](https://ardornxt.slack.com/archives/C0XP71MBL/p1611040650046800) A node can only run contracts from a single account. In other words it can only have one contract runner. ---
**Author:** ![shugo](https://talk.jelurida.com/user_avatar/talk.jelurida.com/shugo/32/22_2.png) [@shugo](https://talk.jelurida.com/u/shugo)\ **Post date:** [19 January 2021 08:04 UTC](https://talk.jelurida.com/t/contract-runner-configuration/132/5 "2021-01-19T08:04:48Z")
EDIT: deleted due to misinformation provided by me 🙂