מדרש אויף שמות 1:11

They imposed upon them taskmasters in order to afflict them with their burdens, and they built storage cities for Pharaoh, Pitom and Raamses (Exodus 1:11).
“They imposed upon him [alav],”²²Although the verse is generally translated “they imposed upon them taskmasters in order to afflict them with their burdens,” the object of the sentence is actually written in singular, such that a more literal translation is “they imposed upon it/him taskmasters to afflict it/him with their burdens.” – “upon them [aleihem]” is not stated, but rather “upon him.” The school of Rabbi Elazar son of Rabbi Shimon taught: It teaches that they brought a brick mold and they hung it on the neck of Pharaoh. If any individual from Israel would say: ‘I am a delicate person,’ they would say to him: ‘Are you more delicate than Pharaoh?’ “Taskmasters [sarei missim],” something upon which bricks are placed [mesim].“In order to afflict him with their burdens” – in order to afflict Pharaoh with the burdens of the Jewish people.²³The brick mold was placed around Pharaoh’s neck in order to make it seem that he too was participating in the building efforts, so that the Israelites would willingly agree to begin working.
“They built storage cities [miskenot] for Pharaoh.” Rav and Shmuel, one said: That endanger [mesakenot] their owners. And one said: That impoverish [memaskenot] their owners, as anyone who engages in construction become poor. The Rabbis say: Storehouses, as it says: “Go and approach that steward” (Isaiah 22:15).²⁴The reference is to Shevna in whose hands the keys to the storehouses were entrusted. See Isaiah 22:22.
“Pitom and Raamses,” Rav and Shmuel, one says: Pitom was its name, and why was it called Raamses? It is because [the buildings] would collapse [mitrossess] one by one. And one says: Raamses was its name, and why was it called Pitom? It is because the opening of the abyss [pi tehom] would swallow [the buildings] one by one.

Variantly: "Chiroth" connotes the place of their (Israel's) freedom ("cheruthan"), a choice place for them (the Egyptians), the place of their idolatry. In the past it was called Pithom, viz. (Exodus 1:11) "And it (Israel) built treasure cities for Pharaoh, Pithom and Ramses." They (the Egyptians) stopped (calling it Pithom) and called it Pi Chachiroth because it disappointed ("me'achereth" [lit., "delayed"]) its worshippers (by not stopping Israel from escaping).

And at that time Pharaoh, king of Egypt, commanded all his people to build unto him a strong ‎palace in Egypt, and he commanded the sons of Jacob likewise to assist in the erection of the ‎building, and the Egyptians built a beautiful and costly palace for the king's residence, and he ‎dwelt therein, and he renewed his government and he reigned securely. And Zebulun, the ‎son of Jacob, died in that year, which was the seventy-second year of the Israelite's going ‎down into Egypt, and Zebulun was one hundred and fourteen years old when he died, and he ‎was placed into a coffin and given into the hands of his children; and in the seventy-fifth year ‎his brother Simeon died, he was one hundred and twenty years old when he died, and he was ‎also put into a coffin and transferred to his children. And Zepho, the son of Eliphaz, the son of ‎Esau, chief of the hosts of Augias, king of Africah, was still enticing Augias day after day to ‎wage war and to fight against the sons of Jacob; but Augias would not consent to do this thing, ‎for his servants had told unto him all concerning the strength of the sons of Jacob, and what ‎they had done unto them in their war with the children of Esau. And after some days Augias ‎listened unto Zepho’s voice, and he consented to fight in Egypt against the sons of Jacob. And ‎Augias collected all his people, a people very numerous even like the sand upon the sea shore, ‎and he turned his face to go towards Egypt to battle. And there was among the servants of ‎Augias a certain youth fifteen years of age, and his name was Balaam, the son of Beor, and the ‎youth was very wise and learned in the art of sorcery. And Augias said unto Balaam: Conjure ‎thou for us with witchcraft, that we ascertain who is to be victorious in this battle, into which ‎we are now going. And Balaam commanded them to bring unto him some wax, and he shaped ‎it into chariots and horsemen, representing the army of Augias and the army of Egypt, and he ‎placed all into water which he had prepared wisely for that purpose, and he took into his ‎hands palm branches, and he bewitched with them the water in his wisdom, and there ‎appeared unto him in the water the likeness of the army of Augias falling before the army of ‎Egypt and the sons of Jacob.‎‏ ‏And Balaam told these things unto Augias, and Augias was ‎discouraged, and he would not arm to go down and fight the Egyptians, but he remained in his ‎city.‎‏ ‏