Let's Build a Compiler
Let's Build a Compiler by Jack Crenshawby Jack Crenshaw
Hacker ApprovedShares rank 4 of 24 online tutorials by recommenders
People recommend it as an accessible, readable introduction that got many started building compilers and was preferred over other books. Critics note the series stops before it becomes truly useful and dislike the baked-in line wrapping.
People recommend it as an accessible, readable introduction that got many started building compilers and was preferred over other books. Critics note the series stops before it becomes truly useful and dislike the baked-in line wrapping.
13 people gave an opinion
- recommend it
- 12
- criticize it
- 1
- approval share
- 92%
Recommended in 5 of 13 months
- November 2025: recommended
- December 2025: recommended
- January 2026: not recommended
- February 2026: not recommended
- March 2026: not recommended
- April 2026: recommended
- May 2026: recommended
- June 2026: not recommended
- July 2026: not recommended
- August 2026: not recommended
- September 2026: not recommended
- October 2026: recommended
- November 2026: not recommended (month in progress)
Why it carries the badge
- 12 people recommend itNeeds 10 or more, met.
- 12 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 5 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Accessible without prior knowledge
“accessible in the sense of being readable without extensive prior knowledge”
Comment from 11 Dec 2025 in “Revisiting "Let's Build a Compiler"” “this was the most accessible body of work”
Comment from 10 Dec 2025 in “Revisiting "Let's Build a Compiler"” Helps newcomers start building compilers
“building a simple compiler for a toy language was a small project that was well within my grasp”
Comment from 10 Dec 2025 in “Revisiting "Let's Build a Compiler"” “I got to learn from Jack Crenshaw's tutorial from comp.compilers newsgroup on USENET.”
Comment from 10 Dec 2025 in “Revisiting "Let's Build a Compiler"” “I loved that tutorial! It got me started down this path.”
Comment from 10 Dec 2025 in “Revisiting "Let's Build a Compiler"” Preferred over other compiler books
“Crenshaw's Let's Build a Compiler was more useful to me than all these books”
Comment from 10 May 2026 in “Making your own programming language is easier than you think (but also harder)” “IMHO the best tutorial is Crenshaw's "Let's Build a Compiler" series.”
Comment from 8 Nov 2025 in “Becoming a compiler engineer”
What people warn about
Each mark is one comment
Baked-in line wrapping in listings
“I've been having a look at the Crenshaw series, and it seems pretty good, but one thing that kinda annoys me is the baked-in line wrapping.”
Comment from 15 Apr 2026 in “Want to Write a Compiler? Just Read These Two Papers (2008)”
Other online tutorials people recommend
The four most recommended other online tutorials, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| CSS-Tricks | 23 | 3 | 88% | 4 | — | Approved |
| Beej's Guide to Network Programmingby Brian "beej Jorgensen" Hall | 16 | 1 | 94% | 7 | 23 yrs3 owners | Approved |
| Learn OpenGL | 15 | 3 | 83% | 3 | — | — |
| Let's Build a Compilerby Jack CrenshawThis page | 12 | 1 | 92% | 5 | — | Approved |
| Patterns.dev | 12 | 7 | 63% | 1 | — | — |
What people said
12 of the 14 comments that mention it, newest first. Each links to the original comment.
“Crenshaw's books are also pretty good too -- even if a bit outdated by now.”
“Crenshaw's Let's Build a Compiler was more useful to me than all these books”
“crenshaw is fantastic but this structural thinking is what separates toy compilers from ones you can actaully extend later”
“I've been having a look at the Crenshaw series, and it seems pretty good, but one thing that kinda annoys me is the baked-in line wrapping.”
“accessible in the sense of being readable without extensive prior knowledge”
“Crenshaw's tutorial doesn't quite reach the point where it becomes useful”
“I loved that tutorial! It got me started down this path.”
“I printed this out (so I could have it with me everywhere) and read it when I was younger.”
“I got to learn from Jack Crenshaw's tutorial from comp.compilers newsgroup on USENET.”
“building a simple compiler for a toy language was a small project that was well within my grasp”
“this was the most accessible body of work”
“IMHO the best tutorial is Crenshaw's "Let's Build a Compiler" series.”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.